# Menu 5 − Motor Control

Mode: RFC‑S

Parameter | 05.001 Output Frequency
--- | ---
Short description | Displays the frequency applied to the motor
Mode | RFC‑S
Minimum | -2000.0 | Maximum | 2000.0
Default |  | Units | Hz
Type | 32 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 1
Coding | RO, FI, ND, NC, PT

The output frequency is not controlled directly, but the Output Frequency (05.001) is a measurement of the frequency applied to the motor.

Parameter | 05.002 Output Voltage
--- | ---
Short description | Displays the r.m.s. line to line voltage at the a.c. terminals of the drive
Mode | RFC‑S
Minimum | −VM_AC_VOLTAGE | Maximum | VM_AC_VOLTAGE
Default |  | Units | V
Type | 16 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 0
Coding | RO, FI, VM, ND, NC, PT

The Output Voltage (05.002) is the r.m.s. line to line voltage at the a.c. terminals of the drive.

Parameter | 05.003 Output Power
--- | ---
Short description | Displays the power flowing via the a.c. terminals of the drive
Mode | RFC‑S
Minimum | −VM_POWER | Maximum | VM_POWER
Default |  | Units | kW
Type | 32 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 3
Coding | RO, FI, VM, ND, NC, PT

The Output Power (05.003) is the power flowing via the a.c. terminals of the drive. The power is derived as the dot product of the output voltage and current vectors, and so this is correct even if the motor parameters are incorrect and the motor model does not align the reference frame with the flux axis of a motor in RFC-A mode. For Open-loop, RFC-A and RFC-S modes a positive value of power indicates power flowing from the drive to motor. For Regen mode a positive value of power indicates power flowing from the supply to the regen drive.

Parameter | 05.005 D.c. Bus Voltage
--- | ---
Short description | Displays the voltage across the d.c. link of the drive
Mode | RFC‑S
Minimum | −VM_DC_VOLTAGE | Maximum | VM_DC_VOLTAGE
Default |  | Units | V
Type | 16 Bit Volatile | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RO, FI, VM, ND, NC, PT

D.c. Bus Voltage (05.005) gives the voltage across the d.c. link of the drive.

Parameter | 05.007 Rated Current
--- | ---
Short description | Set to the rated current rated of the motor
Mode | RFC‑S
Minimum | −VM_RATED_CURRENT | Maximum | VM_RATED_CURRENT
Default | 0.000 | Units | A
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 3
Coding | RW, VM, RA

Rated Current (05.007) is used as follows:

Function | Details
Motor thermal protection | Defines the motor rated current.
Motor pre-heat | Motor pre-heat is set up as a percentage of rated current.
Sensorless low speed mode | The current for low speed sensorless is set-up as a percentage of rated current.
Current limits | Curent limits are set up as a percantage of rated torque producing current.

Parameter | 05.008 Rated Speed
--- | ---
Short description | Set to the rated speed of the motor
Mode | RFC‑S
Minimum | 0.00 | Maximum | 33000.00
Default | 3000.00 | Units | rpm
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 2
Coding | RW

Rated Speed (05.008) is used in congunction with Number Of Motor Poles (05.011) to define the rated frequency and this is used as described in the table below.

Function | Details
Sensorless control thresholds | The thresholds for changes from low speed starting mode to high speed normal operation and vice versa.
Flux controller gain | Rated frequency is to define the gain of the flux controller.

The units for Rated Speed (05.008) are always rpm even if a linear motor is used and Linear Speed Select (01.055) = 1.

Parameter | 05.009 Rated Voltage
--- | ---
Short description | Set to the rated voltage of the motor
Mode | RFC‑S
Minimum | −VM_AC_VOLTAGE_SET | Maximum | VM_AC_VOLTAGE_SET
Default | See exceptions below | Units | V
Type | 16 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 0
Coding | RW, VM, RA

Voltage | Region | Default Value
200V | All | 230
400V | 50Hz | 400
400V | 60Hz | 460
575V | All | 575
690V | All | 690

The Rated Voltage (05.009) is the maximum continuous voltage that is applied to the motor. Some headroom must be allowed if high performance is required at higher speeds. It should be noted that this limit is not applied unless Enable High Speed Mode (05.022) is set to 1.

Rated Voltage (05.009) is used as described in the table below.

Function | Details
Maximum motor voltage | Unless the motor voltage is limited by the maximum output voltage of the inverter the rated voltage value is used as the reference for the flux controller to limit the motor voltage.

Parameter | 05.011 Number Of Motor Poles
--- | ---
Short description | Set to the number of poles of the motor
Mode | RFC‑S
Minimum | 0 | Maximum | 240
Default | 3 | Units | PolePairs
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

* The units relate to the numeric value of the parameter and not the text string.

The numeric value in Number Of Motor Poles (05.011) should be set to the number of motor pole pairs (i.e. number of motor poles / 2). The text strings associated with Number Of Motor Poles (05.011) show the number of motor poles (i.e. the parameter value x 2). If a linear position feedback device is used Number Of Motor Poles (05.011) should be set to 1 (2 Poles).

If Number Of Motor Poles (05.011) = 0 the number of motor poles = 3 (6 Poles).

Parameter | 05.012 Auto-tune
--- | ---
Short description | Defines the auto-tune test to be performed
Mode | RFC‑S
Minimum | 0 | Maximum | 5
Default | 0 | Units |
Type | 8 Bit Volatile | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE, NC

Value | Text
0 | None
1 | Stationary
2 | Rotating
3 | Inertia 1
4 | Inertia 2
5 | Full Stationary

The following describes how an auto-tune test can be initiated and normal operation can be resumed after the test for RFC-S mode:

An auto-tune test cannot be initiated if the drive is tripped or the drive inverter is active, i.e. Drive Healthy (10.001) = 0 or Drive Active (10.002) = 1. The inverter can be made inactive by ensuring that the Final drive enable is inactive, or the Final drive run is inactive and Hold Zero Speed (06.008) = 0.

1. An auto-tune test is initiated by setting Auto-tune (05.012) to a non-zero value and making the Final drive enable and the Final drive run active.
2. All tests that move the motor will move the motor in the forward direction if Reverse Select (01.012) = 0 or the reverse direction if Reverse Select (01.012) = 1.
3. If the auto-tune sequence is completed successfully the Final drive enable is set to the inactive state and Auto-tune (05.012) is set to zero. The Final drive enable can only be set to the active state again by removing the enable and re-applying it. The enable can be removed by setting Drive Enable (06.015) = 0, or by setting bit 0 of the Control Word (06.042) to 0 provided Control Word Enable (06.043) = 1, or by making Hardware Enable (06.029) = 0.
4. If a trip occurs during the auto-tune sequence the drive will go into the trip state and Auto-tune (05.012) is set to zero. As in 4 above the enable must be removed and re-applied before the drive can be restarted after the trip has been reset. However, care should be taken because if the auto-tune was not completed the drive parameters that should have been measured and set up will still have their original values.
5. If the Final drive enable is made active, the Final drive run is inactive and Hold Zero Speed (06.008) = 1 the drive would normally be in the Stop state (i.e. the inverter is active, but the frequency or speed reference is 0).

The following describes the effects of the auto-tune test on the drive parameters for RFC-S mode:

1. All auto-tune tests rely on the motor being stationary when the test is initiated to give accurate results.
2. If Select Motor 2 Parameters (11.045) = 0 then the parameters associated with motor map 1 are updated as a result of the test, and if Select Motor 2 Parameters (11.045) = 1 the parameters associated with motor map 2 are updated.
3. When each stage of the test is completed, the results are written to the appropriate parameters and these parameters saved in the drive non-volatile memory. If Parameter Cloning (11.042) is set to 3 or 4 the parameters are also written to a non-volatile media card fitted in the drive.

The table below shows the parameters required for motor control indicating which should be set by the user and which can be measured with an auto-tune test.

Parameter | Required for | Measured in test
Rated Current (05.007) | Basic control | User set-up
Rated Speed (05.008) | Basic control | User set-up
Rated Voltage (05.009) | Basic control | User set-up
Number Of Motor Poles (05.011) | Basic control | User set-up
Stator Resistance (05.017) | Basic control | 1, 2, 5
Ld (05.024) | Basic control | 1, 2, 5
Maximum Deadtime Compensation (05.059) | Basic control | 1, 2, 5
Current At Maximum Deadtime Compensation (05.060) | Basic control | 1, 2, 5
Current Controller Kp Gain (04.013) | Basic control | 1, 2, 5
Current Controller Ki Gain (04.014) | Basic control | 1, 2, 5
Volts Per 1000rpm (05.033) | Basic control | Not currently measured
Inverted Saturation Characteristic (05.070) | Sensorless control using current injection mode | Not currently measured
Phase Offset At Defined Iq Current (05.077) | Sensorless control using current injection mode | Not currently measured
Low Speed Sensorless Mode Current (05.071) | Sensorless control using current injection mode | Not currently measured
No-load Lq (05.072) | Sensorless control and high preformance current control | 1, 2, 5
Lq At The Defined Iq Current (05.078) | Sensorless control | Not currently measured
Lq At The Defined Id Current (05.084) | Sensorless control | Not currently measured
Motor And Load Inertia (03.018) | Speed controller set-up and torque feed-forwards | 3, 4
Inertia Times 1000 (04.033) | Speed controller set-up and torque feed-forwards | 3, 4
Torque Per Amp (05.032) | Speed controller set-up and torque feed-forwards | Not currently measured
Position Feedback Phase Angle (03.025) | Basic control with position feedback | 1, 2, 5

1: Stationary
This test can be used to measure all the necessary parameters for basic control.

1. A test is performed to locate the flux axis of the motor. If Minimal Movement Phasing Test Angle (05.016) = 0 then motor inductance measurement is used and the motor should not move, otherwise a minimal movement method is used. See Minimal Movement Phasing Test Mode (05.013) for details. If sensorless control is being used (i.e. Sensorless Mode Active (03.078) = 1) then inductance measurement is always used.
2. A stationary test is performed to measure Stator Resistance (05.017), Maximum Deadtime Compensation (05.059) and Current At Maximum Deadtime Compensation (05.060).
3. If Enable Stator Compensation (05.049) = 1 then Stator Base Temperature (05.048) is made equal to Stator Temperature (05.046).
4. A stationary test is performed to locate the flux axis of the motor again in case the motor has moved during the previous test.
5. If sensorless mode is not selected (i.e. Sensorless Mode Active (03.078) = 0) then the position feedback phasing angle measured during stage 1 of this test is compared with the value measured during this stage of the test. If there is a difference of 30o or more then a Autotune 1.6 trip is initiated. Otherwise Position Feedback Phase Angle (03.025) is set up for the position from the position feedback interface selected with Motor Control Feedback Select (03.026). Whether inductance measurement or minimal movement was used to locate the flux Minimal Movement Phasing Test Angle (05.016), Minimal Movement Phasing Test Current (05.015) and Minimal Movement Phasing Test Mechanical Load Phase (05.019) are saved. If inductance measurement is used then the values are set to thier default levels. If minimal movement is used then the values are set as a result of the test.
6. A stationary test is performed to measure Ld (05.024) and No-load Lq (05.072).
7. Stator Resistance (05.017) and Ld (05.024) are used to set up Current Controller Kp Gain (04.013) and Current Controller Ki Gain (04.014). This is only performed once during the test, and so the user can make further adjustments to the current controller gains if required.

It should be noted that because this is a stationary or minimal movement test, it is not possible to check the direction of the position feedback. If the motor power connection phase sequence is incorrect so that the position feedback counts in reverse when the drive applies a phase sequence U-V-W to operate in the forward direction then when the drive is enabled after the auto-tune the motor will jump thought 90o electrical and stop with a current in the motor defined by the current limits. This can be corrected by changing the drive output phase sequence with Reverse Output Phase Sequence (05.042) and then repeating the auto-tuning. This will make the motor rotate correctly in the direction defined by the position feedback rotation. If the position feedback direction is correct the motor will then rotate under control in the required direction, but if the position feedback direction is incorrect the motor will then rotate under control in the wrong direction.

When using any type of encoder with digital commutation signals (i.e. AB Servo) the absolute position is not fully defined until the motor has moved by between 1 and 2 electrical revolutions (i.e. between 120o and 240o mechanical for a 6 pole motor). This means that Position Feedback Phase Angle (03.025) can only be measured correctly using motor inductance measurement (i.e. Minimal Movement Phasing Test Angle (05.016) = 0). Also if Position Feedback Phase Angle (03.025) is measured for a motor using this type of position feedback using a stationary test when the motor has not moved since power-up, or after the position feedback is re-initialised, there can be an error of +/-30o in the result. When the motor subsequently moves, the drive synchronises more accurately to the commutation signal edges and adjusts Position Feedback Phase Angle (03.025) to be correct and then saves the value in the drive. If a stationary auto-tune is performed and the motor is not moved by at least 2 electrical revolutions before powering down again this process is not carried out and the auto-tune should be repeated. When an encoder with digital commutation signals is used there is always an error of up to 30o in the phasing angle during starting until the motor has rotated by 1/3 of an electrical revolution. It should be noted that the +/-30o error in the phasing angle can increase this error to 60o and reduce the possible torque by up to 50%. Once the motor has rotated by 2 electrical revolutions full torque will be available.

The stationary test cannot be used with commutation only type devices, and test 2 below should be used instead.

If inductance measurement is being used to locate the flux axis of the motor (see Minimal Movement Phasing Test Mode (05.013)) and the motor inductance is very high (i.e. low speed motor with high pole number), or the inductance is moderately high and the drive has a much higher power rating than the motor, then the drive may find it difficult to locate the flux axis. If this is a problem and position feedback is being used then the minimal movement method can be performed instead.

2: Rotating
This test can be used to measure all the necessary parameters for basic control. The motor must be unloaded for this test. This test is likely to give a more accurate value for Position Feedback Phase Angle (03.025) than auto-tune test 1 for motors with low saliency or no saliency. If Volts Per 1000rpm (05.033) / (Number Of Motor Poles (05.011) x (No-load Lq (05.072) - (Ld (05.024)) x Rated Current (05.007)) < 200 then the reluctance torque (due to saliency) compared to the torque derived from the magnet flux is too high and this test cannot be used. Note that if sensorless mode is selected Auto-tune 1 test is performed.

1. A rotating test is performed to locate the flux axis of the motor and Position Feedback Phase Angle (03.025) is set up for the position from the position feedback interface selected with Motor Control Feedback Select (03.026). This is done by rotating the motor by 2 electrical revolutions (i.e. up to 2 mechanical revolutions) in the required direction. Minimal Movement Phasing Test Angle (05.016), Minimal Movement Phasing Test Current (05.015) and Minimal Movement Phasing Test Mechanical Load Phase (05.019) are set to thier default values and saved.
2. A stationary test is performed to measure Stator Resistance (05.017), Maximum Deadtime Compensation (05.059) and Current At Maximum Deadtime Compensation (05.060).
3. If Enable Stator Compensation (05.049) = 1 then Stator Base Temperature (05.048) is made equal to Stator Temperature (05.046).
4. A stationary test is performed to measure Ld (05.024) and No-load Lq (05.072).
5. Stator Resistance (05.017) and Ld (05.024) are used to set up Current Controller Kp Gain (04.013) and Current Controller Ki Gain (04.014). This is only performed once during the test, and so the user can make further adjustments to the current controller gains if required.

3: Inertia 1
This test measures the mechanical characteristic of the motor and load by rotating the motor at the speed defined by the present speed reference and injecting a series of speed test signals. This test should only be used provided all the basic control parameters (including Torque Per Amp (05.032)) have been set-up correctly and the speed controller parameters should be set to conservative levels, such as the default values, so that the motor is stable when it runs. The test may give inaccurate results if standard ramp is active, particularly with high inertia low loss loads. The test measures the motor and load inertia, which can be used in automatic set-up of the speed controller gains and in producing a torque feed-forward term. If Mechanical Load Test Level (05.021) is left at its default value of zero then the peak level of the injection signal will be 1% of the maximum speed reference subject to a maximum of 500rpm. If a different test level is required then Mechanical Load Test Level (05.021) should be set to a non-zero value to define the level as a percentage of the maximum speed reference, again subject to a maximum of 500rpm. The user defined speed reference which defines the speed of the motor should be set to a level higher than the test level, but not high enough for flux weakening to become active. In some cases, however it is possible to perform the test at zero speed provided the motor is free to move, but it may be necessary to increase the test signal from the default value. The test will give the correct results when there is a static load applied to the motor and in the presence of mechanical damping. This test should be used if possible, however for sensorless mode, or if the speed controller cannot be set up for stable operation an alternative test is provided (Auto-tune (05.012) = 4 ) where a series of torque levels are applied to accelerate and decelerate the motor to measure the inertia.

1. A rotating test is performed in which the motor is accelerated with the currently selected ramps up to the currently selected speed reference, and this speed is maintained for the duration of the test. Motor And Load Inertia (03.018) and Inertia Times 1000 (04.033) are set up.

4: Inertia 2
Auto-tune test 3 should normally be used for mechanical load measurement, but under some circumstances this test may be used as an alternative. This test is likely to give incorrect results if standard ramp mode is active. A series of progressively larger torque levels are applied to the motor (20%, 40% ... 100% of rated torque) to accelerate the motor up to 3/4 x Rated Speed (05.008) to determine the inertia from the acceleration/deceleration time. The test attempts to reach the required speed within 5s, but if this fails the next torque level is used. When 100% torque is used the test allows 60s for the required speed to be reached, but if this is unsucessful a trip is initiated. To reduce the time taken for the test it is possible to define the level of torque to be used for the test by setting Mechanical Load Test Level (05.021) to a non-zero value. When the test level is defined the test is only carried out at the defined test level and 60s is allowed for the motor to reached the required speed. It should be noted that if the maximum speed allows for flux weakening then it may not be possible to acheive the required torque level to accelerate the motor fast enough. If this is the case, the maximum speed reference should be reduced.

1. The motor is accelerated in the required direction up to 3/4 of the maximum speed reference and then decelerated to zero speed.
2. The test is repeated with progressively higher torques until the required speed is reached.
3. Motor And Load Inertia (03.018) and Inertia Times 1000 (04.033) are set up.

5: Full Stationary
This test is intended to measure as many parameters as possible without rotating the motor. Minimal Movement Phasing Test Mode (05.013) should to be set to indicate whether the motor is free or constrained. The test is carried out as follows:

1. The stationary test described above is performed using inductance measurement.
2. If Stage 1 is successful the test is now complete. If position feedback is being used and the test has failed because the saturation characteristic of the motor cannot be measured (Inductance.004), the position feedback phasing angle is different by more than 30o between the first and second time the motor flux is located (Autotune 1.006), or the motor is not salient enough to use inductance measurement to locate the motor flux (Inductance.003) then the stationary test is repeated using minimal movement instead of inductance measurement to locate the motor flux. If Minimal Movement Phasing Test Angle (05.016) has a value of zero when the test is started Minimal Movement Phasing Test Angle (05.016) is set to an angle equivalent to at least 75 counts from the position feedback device if it is a rotary device and is connected to the P1 position feedback interface on the drive, subject to a minimum of 0.05o if the motor is constrained or 1.0o if the motor is free to rotate. The table below shows how the angle is calculated, subject to a maximum of 0.5o if the motor is constrained or 5.0o if it is free to rotate.. If the device is not included in the table, is a linear device or is not connected to the P1 interface then the minimum values are used. If Minimal Movement Phasing Test Angle (05.016) is non-zero when the test is started then this value is used. If position feedback is not being used or any other trips occurred during the first stationary test the test is aborted and the drive is tripped.
3. If Stage 2 is successful the test is now complete.

NOTE: Further stages will be added to this test in the future, and so it should not be assumed that the test will be complete after the stages given above in future software versions.

Position feedback type | Calculation of minimal movement phasing test angle
AB, FD, FR, AB Servo, FD Servo, FR Servo | 6750 / P1 Rotary Lines Per Revolution (03.034)
SC, SC Hiperface, SC EnDat, SC SSI, SC Servo, SC SC | 6750 / (P1 Rotary Lines Per Revolution (03.034) x 256)
Resolver | 5o
EnDat, SSI, BiSS | 27000 / 2(P1 Comms Bits (03.035) - P1 Rotary Turns Bits (03.033))

The table below shows the trips that can occur during an auto-tune test:

Trip | Reason
Autotune Stopped | The final drive enable or the final drive run were removed before the test was completed.
Resistance.001 | The measured value of Stator Resistance (05.017) exceeded a value of (VFS / √2) / Full Scale Current Kc (11.061), where VFS is the full scale d.c. link voltage.
Resistance.002 | It has not been possible to measure the drive inverter characteristic to define Maximum Deadtime Compensation (05.059) and Current At Maximum Deadtime Compensation (05.060).
Autotune 1.001 | The position feedback did not change when position feedback is being used.
Autotune 1.002 | The motor did not reach the required speed.
Autotune 1.003 | The required commutation signal edge could not be found with commutation signal only position feedback.
Autotune 1.004 | The required angular movement did not occur during a minimal movement test.
Autotune 1.005 | The fine location of the motor flux during a minimal movement test failed.
Autotune 1.006 | The phasing offset angle is meaured twice during a stationary auto-tune and the two values were not within 30degrees.
Autotune 1.007 | The motor was rotating when a minimal movement test was performed to find the phasing offset angle on enable.
Autotune 1.009 | During the final stage of the minimal movement phasing test with a constrained motor it was not possible to achieve the required movement.
Autotune 2.001 | Position feedback direction is incorrect when position feedback is being used.
Autotune 2.002 | A SINCOS encoder with comms is being used for position feedback and the comms position is rotating in the opposite direction to the sine wave based position.
Autotune 3.001 | The measured inertia exceeds the parameter range.
Autotune 3.003 | The mechanical load test has failed to identify the inertia.
Autotune 3.002 | A position feedback device with commutation signals is being used (i.e. AB Servo, FD Servo, FR Servo, SC Servo) and the commutation signals changed in the wrong direction.
Autotune 4 | A position feedback device with commutation signals is being used (i.e. AB Servo, FD Servo, FR Servo, SC Servo) and U signal did not change.
Autotune 5 | A position feedback device with commutation signals is being used (i.e. AB Servo, FD Servo, FR Servo, SC Servo) and V signal did not change.
Autotune 6 | A position feedback device with commutation signals is being used (i.e. AB Servo, FD Servo, FR Servo, SC Servo) and W signal did not change.
Autotune 7 | The motor poles or the position feedback resolution have been set up incorrectly where position feedback is being used. The trip will not occur if Number Of Motor Poles (05.011) ≥ 6 (i.e. 12 poles).
Inductance.003 | The difference between the d and q axis inductance is not large enough to correctly determine the location of the motor flux. If position feedback is being used the measured value for Position Feedback Phase Angle (03.025) may not be reliable. Also the measured values of Ld (05.024) and No-load Lq (05.072) may not correspond to the d and q axis respectively. The test is completed and all the parameters saved to non-volatile memory in the drive, but the user should note that the measured results may not be correct. It should be noted that this trip is not produced if sensorless mode is selected and active (i.e. Sensorless Mode Active (03.078) = 1).
Inductance.004 | During auto-tune test 1 when position feedback is being used (i.e. Sensorless Mode Active (03.078) = 0), the direction of the flux in the motor must be detected by the change of inductance with different currents. This trip is initiated if the change cannot be detected.

Parameter | 05.013 Minimal Movement Phasing Test Mode
--- | ---
Short description | Minimal Movement Phasing Test Mode
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Free
1 | Constrained

If position feedback is being used, i.e. Sensorless Mode Active (03.078) = 1, it is necessary to define the relationship between the motor magnet flux and the position feedback angle with Position Feedback Phase Angle (03.025) (or M2 Position Feedback Phase Angle (21.020) for motor map 2). This can be measured during auto-tuning with a rotating or stationary test. Minimal Movement Phasing Test Mode (05.013), Minimal Movement Phasing Test Current (05.015), Minimal Movement Phasing Test Angle (05.016) and Minimal Movement Phasing Test Mechanical Load Phase (05.019) are used to define the operation of the stationary test. It is also possible to perform the stationary test on drive enable to calculate Position Feedback Phase Angle (03.025), see Phasing Test On Enable (05.014) for details. If position feedback is not being used, Sensorless Mode Active (03.078) = 0, then Position Feedback Phase Angle (03.025) is not relevant, and so these parameters are also not relevant. If Minimal Movement Phasing Test Angle (05.016) is left at its default value of zero the stationary test uses motor inductance measurement to locate the magnet flux in the motor to calculate Position Feedback Phase Angle (03.025). The inductance measurement test does not cause any deliberate movement of the motor during the test, but does rely on the motor being salient under no-load conditions. If the motor is non-salient, i.e. the ratio between the d and q inductance is too small (see Inductance) then inductance measurement cannot be used for the stationary test.

As an alternative to inductance measurement, a test referred to as a minimal movement test, that causes a small movement of the motor, can be used instead. The minimal movement test does not depend on motor saliency, but is not as accurate as the inductance based measurement with high saliency motors where Volts Per 1000rpm (05.033) / (Number Of Motor Poles (05.011) x (No-load Lq (05.072) - (Ld (05.024)) x Rated Current (05.007)) is less than 1000. If the motor has sufficient saliency the inductance test should be used in preference to the minimal movement test. The minimal movement test can be used even if the motor is constrained by a mechanical brake, provided the mechanical system allows sufficient motor movement. For the test to be reliable it is suggested that the position feedback changes by at least 75 counts during the test. If the motor is free to rotate Minimal Movement Phasing Test Mode (05.013) should be left at its default value of zero (Free), otherwise it should be set to one (Constrained). To select the minimal movement test, instead of the inductance measurement, Minimal Movement Phasing Test Angle (05.016) should be set to a non-zero value to define the peak to peak movement required during the test in 0.01o units. For example, if the position feedback has a resolution of 16384 counts per revolution, then for a movement of 75 counts the required angle is 360o x 75 / 16384 = 1.64o. If the motor is constrained then the required movement will need to be set to a lower value as it is unlikely that the drive will be able to achieve a large angular movement against the brake, and so a higher resolution position feedback device may be required. If the motor is free to rotate it is advisable to use an angle of at least 1.00o to prevent non-linear effects such as motor cogging from affecting the result. If the motor is constrained an angle of at least 0.05o should be used where possible. The minimal movement test does not apply a static torque, but an alternating torque, so there should be no net slip against the brake. If the required movement is too high the brake may prevent this and the test will fail. (If a linear position feedback device is being used 360o corresponds to one pole pitch.)

When the minimal movement phasing test is used during auto-tuning the sequence is as follows:

Stage 1:

An a.c. torque of 1% of rated torque is applied and the resulting peak to peak position movement is measured. If this is less than the required peak to peak movement defined by Minimal Movement Phasing Test Angle (05.016) the torque is increased to 2%, 3%, 6%, 12%, 25%, 50% and 100% of rated torque. If the required movement has not been achieved then an Autotune 1.004 trip is initiated and the test is aborted. Once the required movement has been achieved the test moves to the next stage.

Stage 2:

If the motor is not constrained (Minimal Movement Phasing Test Mode (05.013)=0) then it is assumed that the load is a damped or un-damped inertia. In which case the phase shift between the applied torque and the position movement is between -90o and -180o. If a further 90o is allowed for the delay in the current controllers, the total phase shift will be between -90o and -270o, and so it is assumed that the delay is the middle value of -180o. The mechanical load phase is required in the last two stages of this test and it is also used subsequently if a minimal movement test is used on enable to calculate Position Feedback Phase Angle (03.025), and so a value of -180o is written to Minimal Movement Phasing Test Mechanical Load Phase (05.019) and the test moves to the next stage. If the motor is constrained (Minimal Movement Phasing Test Mode (05.013)=1) then the load may appear as a damped or un-damped inertia, or it may appear as a damped or un-damped spring. In this case the mechanical load phase including the delay in the current controllers may be anywhere in the range from 0o to -270o. It is not possible to use a fixed estimate of -180o, and so the mechanical load phase is measured in this stage before the test moves to the next stage.

Stage 3:

The position feedback phase angle is now measured during a series of tests, using the mechanical load phase from the previous stage, and the average result is used as an estimate before proceeding to the next stage of the test.

Stage 4:

The system now has an approximate value for the position feedback phase angle, but a more accurate value can be obtained during this stage which does a series of fine trimming tests. This algorithm should not fail, but if the system is resonant for example, and the result does not converge an Autotune 1.005 trip will occur. If the motor is free (Minimal Movement Phasing Test Mode (05.013)=0) then the test is complete after this stage. If the motor is constrained (Minimal Movement Phasing Test Mode (05.013)=1) then the sequence proceeds to the next stage.

Stage 5:

If the motor is constrained it is possible to check that an error has not occurred in the previous stage giving the position feedback phase angle with an error of 180o. To do this a low frequency torque is applied to the motor. If the necessary movement for this test cannot be obtained an Autotune 1.009 trip is initiated. This stage of the test sequence cannot be used with an unconstrained motor because it would cause the motor to rotate. As the mechanical load phase shift of an unconstrained motor is more predictable this stage of the test is not required.

During the complete auto-tune sequence the series of tests given above is carried out twice (see Auto-tune State (10.107)) and is indicated by states 1 and 3. The results for the position feedback phase angle from each test are compared and if they are different by more than 30o then an Autotune 1.006 trip is initiated, or if the test is successful Position Feedback Phase Angle (03.025) or M2 Position Feedback Phase Angle (21.020), Minimal Movement Phasing Test Current (05.015) and Minimal Movement Phasing Test Mechanical Load Phase (05.019) are written and saved.

When the minimal movement test is selected to determine the phasing offset angle on enable two alternative tests can be selected with Phasing Test On Enable (05.014). The longer test uses the sequence described above for auto-tuning, but the sequence only runs once. If the shorter test is selected the test time is significantly reduced and the stages of the test are as follows.

Stage 1:

The current is increased in the same way as in the auto-tuning sequence except that the sequence begins with the current required for the last auto-tune which was stored in Minimal Movement Phasing Test Current (05.015).

Stage 2:

Not used.

Stage 3:

During auto-tuning this stage uses an average of 16 measured results. During the test on enable a minimum of 4 results are used and a maximum of 16 depending on the variation in the measured values. If consistent results cannot be achieved an Autotune 1.006 trip is initiated. If the motor is free (Minimal Movement Phasing Test Mode (05.013)=0) then the test is complete after this stage. If the motor is constrained (Minimal Movement Phasing Test Mode (05.013)=1) then the sequence proceeds to Stage 5.

Stage 4:

Not used.

Stage 5:

As for auto-tuning.

The results from the short test can be less accurate than for the longer test, but will be improved if a larger movement is required especially with an unconstrained motor. Also the test is only accurate if the motor is stationary before the test begins, and so if the speed is higher than the zero speed threshold (i.e. Zero Speed (10.003)=0) an Autotune 1.007 trip is initiated before the test is attempted.

The following is a summary of the parameters used to set up the stationary phasing tests and the trips that can be initiated by the tests.

Parameter | Function |
Minimal Movement Phasing Test Mode (05.013) | Defines whether the motor is free to rotate or constrained by a mechanical brake for the minimal movement test. |
Phasing Test On Enable (05.014) | Selects a long or short test on enable and defines when the test is carried out. |
Minimal Movement Phasing Test Current (05.015) | Initial current used at the start of the phasing test on enable. |
Minimal Movement Phasing Test Angle (05.016) | Required peak to peak angular movement required for the minimal movement test. If this parameter is zero then inductance measurement is used for the stationary test. |
Minimal Movement Phasing Test Mechanical Load Phase (05.019) | Mechanical load phase angle between applied torque and position movement. |

Trip | Reason
Inductance.003 | The ratio of Ld and Lq is too small. See Inductance trip.
Inductance.004 | The saturation characteristic of the motor cannot be measured.
Autotune 1.004 | The required angular movement could not be achieved during the minimal movement test.
Autotune 1.005 | Stage 4 of the minimal movement test during auto-tuning did not converge.
Autotune 1.006 | During auto-tuning the two minimal movement tests carried out did not give consistent results. During a short minimal movement phasing test on enable Stage 3 did not give consistent results.
Autotune 1.007 | The motor was moving when a minimal movement test was initiated on enable.
Autotune 1.009 | The required movement could not be achieved during stage 5 of a minimal movement test.

It should be noted that the minimal movement test system can be used when position feedback is via the P1 or P2 interfaces on the drive or via a position feedback interface from an option module. However, if the position feedback is via an option module any filtering applied to the speed feedback by the option module must be disabled. This does not apply to the drive position feedback interfaces because the filtering effect of P1 Feedback Filter (03.042) is automatically bypassed during the test.

Parameter | 05.014 Phasing Test On Enable
--- | ---
Short description | Defines a when a stationary test is performed to calculate the Postion Feedback Phase Angle
Mode | RFC‑S
Minimum | 0 | Maximum | 4
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Disabled
1 | Short
2 | Short Once
3 | Long
4 | Long Once

Phasing Test On Enable (05.014) can be used to get the drive to perform a phasing angle test when it is enabled. This test can be used when a non-absolute encoder is used for motor control feedback. The phasing test will measure and modify Position Feedback Phase Angle (03.025), so that the correct offset is applied to run the motor with the non-absolute encoder. Note that the value is not saved in drive non-volatile memory. A test is only carried out when sensorless mode is not active (i.e. Sensorless Mode Active (03.078) = 0). The test can be selected to occur after power-up and each time the position feedback is re-initialised. It is not necessary to perform the test on every enable, but this can be selected if required. The table below shows the possible options.

Phasing Test On Enable (05.014) | Action when Minimal Movement Phasing Test Angle (05.016) is zero | Action when Minimal Movement Phasing Test Angle (05.016) is non-zero
Disabled (0) | No phasing test is carried out on enable | No phasing test is carried out on enable.
Short (1) | A test lasting approximately 0.4s is carried out on every enable | A test lasting approximately 2.0s is carried out of every enable. If Minimal Movement Phasing Test Mode (05.013) is non-zero the test is extended to approximately 8s.
Short Once (2) | A test lasting approximately 0.4s is carried out when the drive is first enabled after power-up, and when the drive is enabled after position feedback selected with Motor Control Feedback Select (03.026) is initialized. | A test lasting approximately 2.0s is carried out when the drive is first enabled after power-up, and when the drive is enabled after position feedback selected with Motor Control Feedback Select (03.026) is initialized. If Minimal Movement Phasing Test Mode (05.013) is non-zero the test is extended to approximately 8s.
Long (3) | A test lasting approximately 2.5s is carried out on every enable | A test lasting approximately 60s is carried out of every enable.
Long Once (4) | A test lasting approximately 2.5s is carried out when the drive is first enabled after power-up, and when the drive is enabled after position feedback selected with Motor Control Feedback Select (03.026) is initialized | A test lasting approximately 60s is carried out when the drive is first enabled after power-up, and when the drive is enabled after position feedback selected with Motor Control Feedback Select (03.026) is initialized.

Minimal Movement Phasing Test Angle (05.016) is zero
The motor inductance is measured to determine the position of the rotor flux. It is recommended that the long test is used as this reduces measurement errors. The long test should always be used when the motor is not constrained during the test (i.e. a motor without a mechanical brake), or with motors that have a high level of saliency even if they are held in position. It should be noted that the motor inductances ( Ld (05.024) and No-load Lq (05.072) ) are checked before the test is carried out, and if the difference is not sufficient (see Inductance) then the drive will trip. Therefore, if the motor inductances have not been measured with auto-tuning or changed from their default values of zero the drive will trip when the drive is enabled. This test, in common with the stationary auto-tune test, cannot be used with commutation only type feedback, i.e. when P1 Device Type (03.038) is set to Commutation Only. Most motors have a positive saturation characteristic so that increasing the current in the flux axis increases motor saturation. It is possible with some motor designs for the characteristic to be reversed. If this is the case the phase angle measurement on enable will produce a value that is 180o from the real value. If this is the case Inverted Saturation Characteristic (05.070) should be set to one.

Minimal Movement Phasing Test Angle (05.016) is non-zero
A minimal movement test is used to determine the position of the rotor flux. See Minimal Movement Phasing Test Mode (05.013) for details. This test cannot be used with any position feedback devices that use commutation signals (i.e. AB Servo, FD Servo, FR Servo, SC Servo or Commutation Only). A stationary auto-tune must be carried out before minimal movement is used for the phasing test on enable as it provides values for Minimal Movement Phasing Test Current (05.015) and Minimal Movement Phasing Test Mechanical Load Phase (05.019). If the motor is constrained then Minimal Movement Phasing Test Mode (05.013) should be set to one during the auto-tuning so that the correct value is set in Minimal Movement Phasing Test Mechanical Load Phase (05.019) by the test. Normally Minimal Movement Phasing Test Mode (05.013) should also be set to one for the phasing test on enable, however this extends the lenght of the test. Provided the auto-tune has set the correct value in Minimal Movement Phasing Test Mechanical Load Phase (05.019) it should be possible to change Minimal Movement Phasing Test Mode (05.013) back to zero after the auto-tune to reduce the length of the phasing test on enable.

Parameter | 05.015 Minimal Movement Phasing Test Current
--- | ---
Short description | Minimal Movement Phasing Test Current
Mode | RFC‑S
Minimum | 0 | Maximum | 7
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background Read/Write
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | 1%
1 | 2%
2 | 3%
3 | 6%
4 | 12%
5 | 25%
6 | 50%
7 | 100%

See Minimal Movement Phasing Test Mode (05.013).

Parameter | 05.016 Minimal Movement Phasing Test Angle
--- | ---
Short description | Minimal Movement Phasing Test Angle
Mode | RFC‑S
Minimum | 0.00 | Maximum | 25.00
Default | 0.00 | Units | °
Type | 16 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 2
Coding | RW

See Minimal Movement Phasing Test Mode (05.013).

Parameter | 05.017 Stator Resistance
--- | ---
Short description | Defines the resistance of the motor stator
Mode | RFC‑S
Minimum | 0.000000 | Maximum | 1000.000000
Default | 0.000000 | Units | Ω
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 6
Coding | RW, RA

The motor parameters used by the drive are derived from the star connected per phase equivalent circuit of a permanent magnet motor shown below.

Stator Resistance (05.017) = R

Ld (05.024) = L in the d (flux) axis

No-load Lq (05.072) = L in the q (torque) axis with no current in the motor

Lq At The Defined Iq Current (05.078) = L in the q axis with Id = 0 and Iq = Lq At The Defined Iq Current (05.078)

Lq At The Defined Id Current (05.084) = L in the q axis with Id = Lq At The Defined Id Current (05.084) and Iq = 0.

Stator Resistance (05.017) is used as described in the table below.

Function | Details
Control above low speeds with sensorless control | The stator resistance is used by the algorithm that detemines the rotor position.
Current controller integral gain set-up | During auto-tuning the stator resistance is used in the calculation of the current controller integral gain.
High performance current control | If high performance current control is selected the stator resistance is used in the control for both d and q axis current.

Parameter | 05.018 Maximum Switching Frequency
--- | ---
Short description | Defines the maximum switching frequency that can be used by the drive
Mode | RFC‑S
Minimum | 0 | Maximum | VM_SWITCHING_FREQUENCY
Default | 3 | Units | kHz
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE, VM, RA

Value | Text
0 | 2
1 | 3
2 | 4
3 | 6
4 | 8
5 | 12
6 | 16

Maximum Switching Frequency (05.018) should be set to the required PWM switching frequency. The drive inverter will operate at this frequency unless the inverter temperature becomes too hot. Under these conditions the drive will reduce the switching frequency in an attempt to avoid tripping (see Auto-switching Frequency Change (05.035) ). The actual switching frequency is shown in Switching Frequency (05.037). The switching frequency has a direct effect on the sample rate for the current controllers (see Current Controller Kp Gain (04.013)). All other control tasks are at a fixed rate.

Task |
Speed controller (RFC-A, RFC-S) | 250μs
D.c. link voltage controller | 1ms
Flux controller (RFC-A, RFC-S) | 1ms

Parameter | 05.019 Minimal Movement Phasing Test Mechanical Load Phase
--- | ---
Short description | Minimal Movement Phasing Test Mechanical Load Phase
Mode | RFC‑S
Minimum | -180 | Maximum | 179
Default | -180 | Units | °
Type | 16 Bit User Save | Update Rate | Background read/write
Display Format | Standard | Decimal Places | 0
Coding | RW

See Minimal Movement Phasing Test Mode (05.013).

Parameter | 05.021 Mechanical Load Test Level
--- | ---
Short description | Mechanical Load Test Level
Mode | RFC‑S
Minimum | 0 | Maximum | 100
Default | 0 | Units | %
Type | 8 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Auto-tune (05.012).

Parameter | 05.022 Enable High Speed Mode
--- | ---
Short description | Set to 1 to enable high speed mode
Mode | RFC‑S
Minimum | -2 | Maximum | 2
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
-2 | Limit
-1 | Limit (Servo)
0 | Disable
1 | Enable (Servo)
2 | Enable

Care must be taken when high speed mode is not set to Disable (0) to avoid damaging the drive. The voltage produced by the magnet flux is proportional to speed. For high speed operation the drive must apply currents to the motor to counter-act the flux produced by the magnets. It is possible to operate the motor at very high speeds that would give a very high motor terminal voltage, but this voltage is prevented by the action of the drive. If however, the drive is disabled (or tripped) when the motor voltages would be higher than the rating of the drive without the currents to counter-act the flux from the magnets, it is possible to damage the drive. If high speed mode is enabled the motor speed must be limited to the levels given in the table below unless an additional hardware protection system is used to limit the voltages applied to the drive output terminals to a safe level.

Drive voltage rating | Maximum motor speed (rpm) | Maximum safe line to line voltage at the motor terminals (V r.m.s.)
200 | 400 x 1000 / (Ke x √2) | 400 / √2
400 | 800 x 1000 / (Ke x √2) | 800 / √2
575 | 955 x 1000 / (Ke x √2) | 955 / √2
690 | 1145x 1000 / (Ke x √2) | 1145 / √2

Ke is the ratio between r.m.s. line to line voltage produced by the motor and the speed in V/1000rpm.

Disabled (0):
The motor flux is not modified to limit the motor voltage to the level defined by Rated Voltage (05.009). The motor voltage will increase as the speed is increased until the motor line to line voltage x √2 is equal to the d.c. link voltage (D.c. Bus Voltage (05.005)). It will not be possible to further increase the speed significantly. This mode is safe because the motor voltage with no current flowing in the motor cannot exceed a level that can damage the drive provided Position Feedback Phase Angle (03.025) is correct for the motor. Note that if Position Feedback Phase Angle (03.025) is modified by the user to change the flux level in the motor then it is possible to damage the drive on disable as described above. It should be noted that if Disable mode is selected, but saliency torque is being exploited (i.e. Active Saliency Torque Mode (05.066) is non-zero) then the drive automatically provides protection against damage by operating in Limit (Servo) mode as described below.

Limit (Servo) (-1):
The motor flux is modified to limit the motor voltage to the level defined by Rated Voltage (05.009). An Over Speed.1 trip is initiated if the measured motor speed exceeds the levels defined in the table above to protect the drive. This mode is intended for dynamic servo type applications with motors that have relatively low saliency. If control using saliency is disabled, or it is enabled but the motor has low saliency (i.e. Active Saliency Torque Mode (05.066) is showing disabled or low saliency operation) then the drive will not restrict the torque requested from the motor to prevent the motor from exceeding its voltage based torque limit. If the motor is operated at or close to this limit it can become unstable, or the drive can lose control of the motor. This is not generally a problem for servo motors as they do not go close to their torque limit or only operate transiently in flux weakening during the last part of their acceleration to maximum speed, and so the flux controller is too slow to provide much flux weakening. Limit (Servo) mode should not be used with high saliency motors (i.e. Active Saliency Torque Mode (05.066) is showing high saliency operation), and so if this is selected for a high saliency motor the drive will automatically operate in Limit mode as described below.

Limit (-2):
This is similar to Limit (Servo) mode except that the motor torque is restricted to prevent the drive from operating close to, or beyond, the voltage based torque limit of the motor. This prevents the motor from operating in a region where it could become unstable, or the drive could lose control of the motor. This is not generally a problem for servo motors as they do not go close to their torque limit or only operate transiently in flux weakening during the last part of their acceleration to maximum speed, and so the flux controller is too slow to provide much flux weakening. However, for more general purpose motors for slower applications, such as fans and pumps, it may be necessary for the drive to prevent the motor from operating close to its voltage based torque limit.

Enable (Servo) (1):
This is similar to Limit (Servo) mode except that a trip is not produced if the motor speed exceeds the maximum safe level. An indication that cannot be cleared is stored in Potential Drive Damage Conditions (10.106) and saved on power-down. The motor manufacturer should always be consulted before using this mode as care must be taken not to de-magnetise the motor.

Enable (2):
This is similar to Limit mode except that a trip is not produced if the motor speed exceeds the maximum safe level. An indication that cannot be cleared is stored in Potential Drive Damage Conditions (10.106) and saved on power-down. The motor manufacturer should always be consulted before using this mode as care must be taken not to de-magnetise the motor.

Parameter | 05.023 D.c. Bus Voltage High Range
--- | ---
Short description | Displays the d.c. bus level but with a higher range
Mode | RFC‑S
Minimum | −VM_HIGH_DC_VOLTAGE | Maximum | VM_HIGH_DC_VOLTAGE
Default |  | Units | V
Type | 16 Bit Volatile | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RO, FI, VM, ND, NC, PT

D.c. Bus Voltage High Range (05.023) provides voltage feedback that has lower resolution and a higher range than D.c. Bus Voltage (05.005), and so it is possible to determine the d.c. link voltage even if this exceeds the level of the over-voltage trip. It should be noted that due to tolerances, D.c. Bus Voltage High Range (05.023) may not correspond exactly with the level given by D.c. Bus Voltage (05.005). In a system with parallel power modules where the control pod is remote from any of the power modules, this parameter always shows zero.

Parameter | 05.024 Ld
--- | ---
Short description | Defines the inductance in the flux axis
Mode | RFC‑S
Minimum | 0.000 | Maximum | 500.000
Default | 0.000 | Units | mH
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 3
Coding | RW, RA

D axis inductance, see Stator Resistance (05.017) for more details.

Ld (05.024) is used as described in the table below.

Function | Details
Current controller gain set-up | During auto-tuning Ld is used in calculating the current controller gains.
High performance current control | If high performance current control is selected (Current Controller Mode (04.030) =1) Ld is used by the controller in d axis.
Low speed operation with sensorless control | If injection mode is used (RFC Low Speed Mode (05.064) = 0) for low speed operation Ld defines the gain of the system.
Flux controller gain | Ld is used in deriving the gain of the controller which controls the motor voltage at high speed.

Parameter | 05.026 High Dynamic Performance Enable
--- | ---
Short description | Set to 1 to enable High Dynamic Performance
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

Whatever the value of High Dynamic Performance Enable (05.026) a feed-forward term based on the estimated level of flux in the motor and the motor speed is used to improve the performance of the current controllers and to avoid transients during spinning start. However, if High Dynamic Performance Enable (05.026) = 1 additional feed-forward terms are provided to remove the effects of cross-coupling between the flux and torque axes. This improves the performance of the current controllers under dynamic conditions at high speeds. It should be noted that High Dynamic Performance Enable (05.026) has no effect if sensorless control is active (i.e. Sensorless Mode Active (03.078) = 1).

Parameter | 05.027 Flux Control Gain
--- | ---
Short description | Flux Control Gain
Mode | RFC‑S
Minimum | 0.1 | Maximum | 10.0
Default | 1.0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW

If Flux Control Gain (05.027) is set to the default value of unity the system that controls the motor voltage is automatically set up based on the motor parameters to give stable operation under most conditions. Some motors which have concentrated windings can cause significant harmonic currents which in turn disturb the voltage controller at higher speeds where the voltage controller is active to limit the motor voltage. To reduce this effect the gain can be reduced. The gain can also be increased for applications with fast acceleration to improve the response of the voltage controller in limiting the motor voltage.

Parameter | 05.028 Torque Linearisation Disable
--- | ---
Short description | Torque Linearisation Disable
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 1 | Units |
Type | 1 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

If high saliency control is active (i.e. Active Saliency Torque Mode (05.066) = 2) the drive applies compensation to give approximately a linear realtionship between the torque reference and actual torque for speed and torque control modes. In some cases this may introduce unacceptable system noise. If Torque Linearisation Disable (05.028) is left at its default value of 0 the linearisation system is active. If Torque Linearisation Disable (05.028) is set to 1 then the linearisation system is disabled. Torque linearisation is disabled if sensorless mode is active, i.e. Sensorless Mode Active (03.078) = 1.

Parameter | 05.031 Voltage Controller Gain
--- | ---
Short description | Defines the proportional gain of the d.c. link voltage controller
Mode | RFC‑S
Minimum | 1 | Maximum | 30
Default | 1 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

Voltage Controller Gain (05.031) can be used to modify the proportional gain of the d.c. link voltage controller used for standard ramp and supply loss control.

Parameter | 05.032 Torque Per Amp
--- | ---
Short description | Defines the torque per amp constant (Kt) for the motor
Mode | RFC‑S
Minimum | 0.00 | Maximum | 500.00
Default | 1.60 | Units | Nm/A
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 2
Coding | RW, BU

Torque Per Amp (05.032) is used for automatic speed controller gain set up and to calculate the inertia in autotune tests 3 and 4, and so the correct value for the motor should be entered if these features are used.

Parameter | 05.033 Volts Per 1000rpm
--- | ---
Short description | Volts per 1000rpm
Mode | RFC‑S
Minimum | 0 | Maximum | 10000
Default | 98 | Units | V
Type | 16 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW

Volts Per 1000rpm (05.033) defines the r.m.s. line voltage produced by the motor flux at 1000rpm, i.e. running at this speed with no current in the motor.

Volts Per 1000rpm (05.033) is used as described in the table below.

Function | Details
Voltage feed-forwards | Provides voltage feed-forwards for the current control system.
Over-speed protection | Ke is used to determine the trip speed if Enable High Speed Mode (05.022) is set to Limit mode
Low speed operation with sensorless control | If "non-salient" mode is selected Ke is used in defining the controller gain.
Rated torque angle | If the drive defines Rated Torque Angle (05.089) no-load Lq is used in the calculation.

Parameter | 05.035 Auto-switching Frequency Change
--- | ---
Short description | Defines auto-switching frequency control with thermal model
Mode | RFC‑S
Minimum | 0 | Maximum | 2
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Enabled
1 | Disabled
2 | No Ripple Detect

The drive inverter can be damaged if the temperature is too high. The inverter can also be damaged or the lifetime of the power devices reduced, if the temperature ripple of the devices is too high. Auto-switching Frequency Change (05.035) defines the action taken if the drive inverter becomes too hot or the temperature ripple becomes too high.

Enabled:
If the inverter becomes too hot or the ripple temperature is higher than the level defined by Maximum Inverter Temperature Ripple (05.039) the switching frequency is reduced in an attempt to prevent tripping.

Disabled:
The switching frequency is not reduced, and so the drive will trip if the inverter is too hot or the temperature ripple is too high.

No Ripple Detect:
The switching frequency is reduced if the inverter temperature, but not the temperature ripple is too high. If the temperature ripple exceeds the level defined by Maximum Inverter Temperature Ripple (05.039) then the drive will trip.

The switching frequency is changed in steps defined by Auto-switching Frequency Step Size (05.036). For example with a switching frequency of 16kHz and a step size of two, the frequency will be reduced to 8kHz, then 4kHz etc. Minimum Switching Frequency (05.038) defines the minimum switching frequency that the system will attempt to use. If the switching frequency needs to switch to a lower level, then the drive will trip. If Minimum Switching Frequency is changed the new value will only become active when Switching Frequency is at or above the minimum value.

Parameter | 05.036 Auto-switching Frequency Step Size
--- | ---
Short description | Auto-switching frequency redcution step size
Mode | RFC‑S
Minimum | 1 | Maximum | 2
Default | 2 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Auto-switching Frequency Change (05.035).

Parameter | 05.037 Switching Frequency
--- | ---
Short description | Displays the current switching frequency used by the drive
Mode | RFC‑S
Minimum | 0 | Maximum | 6
Default |  | Units | kHz
Type | 8 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, TE, ND, NC, PT

Value | Text
0 | 2
1 | 3
2 | 4
3 | 6
4 | 8
5 | 12
6 | 16

Shows the actual inverter switching frequency after the auto-change function.

Parameter | 05.038 Minimum Switching Frequency
--- | ---
Short description | Minuimum Switching Frequency
Mode | RFC‑S
Minimum | 0 | Maximum | VM_MIN_SWITCHING_FREQUENCY
Default | 0 | Units | kHz
Type | 8 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE, VM

Value | Text
0 | 2
1 | 3
2 | 4
3 | 6
4 | 8
5 | 12
6 | 16

See Auto-switching Frequency Change (05.035).

Parameter | 05.039 Maximum Inverter Temperature Ripple
--- | ---
Short description | Maximum Inverter Temperature Ripple
Mode | RFC‑S
Minimum | 20 | Maximum | 60
Default | 60 | Units | °C
Type | 8 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW

Maximum Inverter Temperature Ripple (05.039) defines the maximum inverter temperature ripple allowed before the switching frequency is reduced. See Auto-switching Frequency Change (05.035).

Parameter | 05.041 Voltage Headroom
--- | ---
Short description | Voltage Headroom
Mode | RFC‑S
Minimum | 0 | Maximum | 20
Default | 0 | Units | %
Type | 8 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW

The voltage applied to the motor is always limited by Rated Voltage (05.009). When Voltage Headroom (05.041) is set to its default value of zero the output voltage of the inverter is also limited to a level equivalent to full modulation, which is the supply voltage minus voltage drops within the inverter itself. Depending on the relative values of the supply voltage and Rated Voltage (05.009) there may be some headroom between the rated voltage limit and the maximum possible voltage from the inverter to allow the current control system to give good dynamic performance. In some applications it is useful to enforce some headroom between the maximum allowed motor voltage and the inherent limit imposed by the inverter. If the supply voltage is known this can be done by setting Rated Voltage (05.009) to a suitable value below the supply voltage level, however, it is more convenient to set Rated Voltage (05.009) to the actual rated voltage of the motor, and to use Voltage Headroom (05.041) to enforce the voltage headroom. This parameter can be used to increase the headroom between the maximum modulation limit and the maximum motor voltage from zero up to 20% of the maximum modulation limit. For example, if the supply voltage is 400V then a value of 10% will give a voltage headroom of approximately 40V.

Parameter | 05.042 Reverse Output Phase Sequence
--- | ---
Short description | Set to 1 to reverse the sequence on the output phases
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

If Reverse Output Phase Sequence (05.042) = 0 the output phase sequence is U-V-W when Output Frequency (05.001) is positive and W-V-U when Output Frequency (05.001) is negative. If Reverse Output Phase Sequence (05.042) = 1 the output phase sequence is reversed so that the phase sequence in W-V-U for positive frequencies and U-V-W for negative frequencies.

Parameter | 05.044 Stator Temperature Source
--- | ---
Short description | Defines the source of the stator temperature
Mode | RFC‑S
Minimum | 0 | Maximum | 6
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | An In 3
1 | User
2 | P1 Drive
3 | P1 Slot1
4 | P1 Slot2
5 | P1 Slot3
6 | P1 Slot4

The stator temperature can be used to compensate for changes in stator resistance. See Stator Temperature Coefficient (05.047). Stator Temperature Source (05.044) is used to select the source for the stator temperature measurement.

Stator Temperature Source (05.044) | Source | Comments
0 | Analog Input 3 Thermistor Temperature (07.050) | Analog input 3 must be set up for the correct temperature feedback device
1 | User Stator Temperature (05.045) | The user can provide a stator temperature value. If an alternative feedback device is to be used or the user provides an algorithm to model the stator temperature.
2 | P1 Thermistor Temperature (03.122) | P1 position feedback interface must be set up for the correct temperature feedback device
3-6 | Option slot P1 Thermistor Temperature (xx.122) | A position feedback category option module must be fitted and the P1 position feedback must be set up for the correct temperature feedback device

Parameter | 05.045 User Stator Temperature
--- | ---
Short description | Defines the stator temperature as set by the user
Mode | RFC‑S
Minimum | -50 | Maximum | 300
Default | 0 | Units | °C
Type | 16 Bit Volatile | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Stator Temperature Source (05.044).

Parameter | 05.046 Stator Temperature
--- | ---
Short description | Displays the temperature of the motor stator
Mode | RFC‑S
Minimum | -50 | Maximum | 300
Default |  | Units | °C
Type | 16 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

See Stator Temperature Source (05.044).

Parameter | 05.047 Stator Temperature Coefficient
--- | ---
Short description | Defines the coefficient used to calculate the temperature of the motor stator
Mode | RFC‑S
Minimum | 0.00000 | Maximum | 0.10000
Default | 0.00390 | Units | 1/°C
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 5
Coding | RW

Temperature Compensated Stator Resistance (05.050) shows the stator resistance from the active motor that is being used by the drive for motor control. If Enable Stator Compensation (05.049) = 0 and motor 1 is selected then Temperature Compensated Stator Resistance (05.050) is equal to Stator Resistance (05.017). If Enable Stator Compensation (05.049) = 1 the value of Stator Resistance (05.017) is not changed, but Temperature Compensated Stator Resistance (05.050) is derived as follows:

α = Stator Temperature Coefficient (05.047) and this is the temperature coefficient for the stator winding at 20oC as a proportion of the resistance per degree C.

Temperature Compensated Stator Resistance (05.050) = Stator Resistance (05.017) x [1 + (Stator Temperature (05.046) – 20oC) x α] / [1 + (Stator Base Temperature (05.048) - 20oC) x α]

Stator Resistance (05.017) and Stator Base Temperature (05.048) can be set up by the user with the stator resistance at a given temperature. The preferred method is for the Stator Resistance (05.017) to be measured and set up using the auto-tuning system (See Auto-tune (05.012)). If Enable Stator Compensation (05.049) = 1 when the auto-tuning is carried out the Stator Base Temperature (05.048) will be updated automatically with Stator Temperature (05.046).

The temperature compensation system can only function correctly if the Stator Temperature Coefficient (05.047) is set up correctly. The default value is suitable for copper or aluminium windings and should not need to be adjusted for these materials provided the temperature measurement is a reasonable measure of the winding temperature. If the temperature measurement is not closely coupled to the winding it may be necessary to adjust Stator Temperature Coefficient (05.047) for correct compensation.

Parameter | 05.048 Stator Base Temperature
--- | ---
Short description | Defines the base temperature used to calculate the temperature of the motor stator
Mode | RFC‑S
Minimum | -50 | Maximum | 300
Default | 0 | Units | °C
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Stator Temperature Coefficient (05.047).

Parameter | 05.049 Enable Stator Compensation
--- | ---
Short description | Set to 1 to enable stator compensation
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Stator Temperature Coefficient (05.047).

Parameter | 05.050 Temperature Compensated Stator Resistance
--- | ---
Short description | Final stator resistance value used by the drive including temperature compensation
Mode | RFC‑S
Minimum | 0.000000 | Maximum | 1000.000000
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 6
Coding | RO, ND, NC, PT

Temperature Compensated Stator Resistance (05.050) shows the stator resistance value for the active motor that is being used by the drive including the effect of temperature compensation.

Parameter | 05.051 Rotor Temperature Source
--- | ---
Short description | Defines the source of the rotor temperature
Mode | RFC‑S
Minimum | 0 | Maximum | 6
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | An In 3
1 | User
2 | P1 Drive
3 | P1 Slot1
4 | P1 Slot2
5 | P1 Slot3
6 | P1 Slot4

The rotor temperature can be used to compensate for changes in rotor resistance that affects the motor slip and hence the rated speed in Open-loop or RFC-A mode, or the magnet flux that affects motor torque in RFC-S mode. See Rotor Temperature Coefficient (05.054) for details. Rotor Temperature Source (05.051) is used to select the source for the rotor temperature measurement.

Rotor Temperature Source (05.051) | Source | Comments
0 | Analog Input 3 Thermistor Temperature (07.050) | Analog input 3 must be set up for the correct temperature feedback device
1 | User Rotor Temperature (05.052) | The user can provide a rotor temperature value if an alternative feedback device is to be used or the user provides an algorithm to model the rotor temperature
2 | P1 Thermistor Temperature (03.122) | P1 position feedback interface must be set up for the correct temperature feedback device
3-6 | Option Slot P1 Thermistor Temperature (xx.122) | A position feedback category option module must be fitted and the P1 position feedback must be set up for the correct temperature feedback device

Parameter | 05.052 User Rotor Temperature
--- | ---
Short description | Defines the temperature of the motor as set by the user
Mode | RFC‑S
Minimum | -50 | Maximum | 300
Default | 0 | Units | °C
Type | 16 Bit Volatile | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Rotor Temperature Source (05.051).

Parameter | 05.053 Rotor Temperature
--- | ---
Short description | Displays the temperature of the motor rotor
Mode | RFC‑S
Minimum | -50 | Maximum | 300
Default |  | Units | °C
Type | 16 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

See Rotor Temperature Source (05.051).

Parameter | 05.054 Rotor Temperature Coefficient
--- | ---
Short description | Defines the coefficient used to calculate the temperature of the rotor
Mode | RFC‑S
Minimum | 0.00000 | Maximum | 0.10000
Default | 0.00100 | Units | 1/°C
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 5
Coding | RW

The flux produced by the magnets in a permanent magnet motor varies with rotor temperature, and this in turn affects the relationship between the motor current and torque. Rotor Temperature Compensation (05.057) shows the compensation factor that is applied to convert from the torque reference to the torque producing current reference. If Enable Rotor Compensation (05.056) = 0 no compensation is applied in converting from the torque reference to the torque producing current reference (i.e. Rotor Temperature Compensation (05.057) = 1.000). If Enable Rotor Compensation (05.056) = 1 then Rotor Temperature Compensation (05.057) is calculated as follows:

Rotor Temperature Compensation (05.057) = 1 – [(Rotor Temperature (05.053) – Rotor Base Temperature (05.055)) x Rotor Temperature Coefficient (05.054)]
The default value of Rotor Temperature Coefficient (05.054) is a typical value for the magnets used in most permanent magnet motors. However, if the thermal coupling between the rotor and the temperature measuring device is poor it may be necessary to adjust Rotor Temperature Coefficient (05.054) to give better compensation.

Parameter | 05.055 Rotor Base Temperature
--- | ---
Short description | Defines the base temperature used to calculate the temperature of the rotor
Mode | RFC‑S
Minimum | -50 | Maximum | 300
Default | 0 | Units | °C
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Rotor Temperature Coefficient (05.054).

Parameter | 05.056 Enable Rotor Compensation
--- | ---
Short description | Set to 1 to enable rotor compensation
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Rotor Temperature Coefficient (05.054).

Parameter | 05.057 Rotor Temperature Compensation
--- | ---
Short description | Factor to convert from torque to current based on rotor temperature
Mode | RFC‑S
Minimum | 0.000 | Maximum | 2.000
Default |  | Units |
Type | 16 Bit Volatile | Update Rate | Background
Display Format | Standard | Decimal Places | 3
Coding | RO, ND, NC, PT

Rotor Temperature Compensation (05.057) shows the conversion factor used between the torque reference and the torque producing current.

Parameter | 05.059 Maximum Deadtime Compensation
--- | ---
Short description | Shows the deadtime compensation used to compensate for dead-time effects in the inverter
Mode | RFC‑S
Minimum | 0.000 | Maximum | 10.000
Default | 0.000 | Units | µs
Type | 16 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 3
Coding | RO, NC, PT

Maximum Deadtime Compensation (05.059) is the deadtime compensation used to compensate for dead-time effects in the inverter. This level of compensation is used when the drive output current is above Current At Maximum Deadtime Compensation (05.060). Both of these values related to dead-time compensation are measured during auto-tuning and cannot be set by the user. It should be noted that if the auto-tuning test is not performed and Maximum Deadtime Compensation (05.059) = 0 then dead-time compensation is disabled. Although it is not recommended, it is possible to disable dead-time compensation by setting Disable Deadtime Compensation (05.061) = 1.

Parameter | 05.060 Current At Maximum Deadtime Compensation
--- | ---
Short description | Current at which maximum deadtime compensation is applied
Mode | RFC‑S
Minimum | 0.00 | Maximum | 100.00
Default | 0.00 | Units | %
Type | 16 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 2
Coding | RO, NC, PT

See Maximum Deadtime Compensation (05.059).

Parameter | 05.061 Disable Deadtime Compensation
--- | ---
Short description | Disable Deadtime Compensation
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Maximum Deadtime Compensation (05.059).

Parameter | 05.063 Sensorless Mode Current Ramp
--- | ---
Short description | Sensorless Mode Current Ramp
Mode | RFC‑S
Minimum | 0.00 | Maximum | 1.00
Default | 0.20 | Units | s
Type | 8 Bit User Save | Update Rate | Background Write
Display Format | Standard | Decimal Places | 2
Coding | RW

See RFC Low Speed Mode (05.064).

Parameter | 05.064 RFC Low Speed Mode
--- | ---
Short description | Defines the low speed mode of the drive when position feedback is not being used
Mode | RFC‑S
Minimum | 0 | Maximum | 5
Default | 2 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text | Description
0 | Injection | High frequency injection mode
1 | Non-salient | Non-salient motor mode
2 | Current | Current vector mode with initial test to determine the rotor position
3 | Current No Test | Current vector mode without initial test to determine the rotor position
4 | Current Step | Current vector mode with no test and step changes in current between low/high speed modes
5 | Current Only | Current vector mode always active

If sensorless mode is being used and is active (i.e. Sensorless Mode Active (03.078) = 1) and the motor is operating at low speed then a low speed algorithm must be used to control the motor. The change between the low speed and normal operation algorithms is related to the drive output frequency. An upper threshold is provided for the change from low speed to normal operation, and a lower threshold is provided for the change back from normal to low speed operation as given in the table below. These values are a percentage of Rated Speed (05.008). If high saliency control is being used ( Active Saliency Torque Mode (05.066) = 2) then the lower threshold is always 15% and the upper threshold is 20%.

Switching Frequency (05.037) | Lower Threshold | Upper Threshold
2kHz | 5% | 10%
3kHz | 5% | 10%
4kHz | 5% | 10%
6kHz | 10% | 15%
8kHz | 10% | 15%
12kHz | 15% | 20%
16kHz | 15% | 20%

RFC Low Speed Mode (05.064) is used to select the algorithm to be used as described below. The following should be noted:

1. Non-salient or Current modes should not be used for motors with high saliency.
2. Non-salient mode is a legacy mode and Current mode should always be used in preference to Non-salient mode.

3. Torque control can be used with the "Injection" starting method in the same way as with position feedback. However if torque control is to be used in an application where the other starting methods are used then the following should be considered: Torque control should not be enabled until the low speed algorithm is no longer active and the motor speed must not drop to a level where the low speed mode will become active again while torque control is active. This means that the motor must be started in speed control and torque control should only be selected when the speed is high enough. To stop the motor the drive can simply be disabled or the run command should be removed for the drive to stop the motor. Removing the run causes the drive to switch from torque control to speed control, and so the motor speed can be reduced back down though the range where the low speed algorithm is active.

0: Injection
A high frequency signal is injected into the motor to detect the motor flux axis. For this to operate correctly the motor must remain salient while the low speed mode is active. The no-load inductance parameters are checked by the drive on enable and if the motor is not sufficiently salient then a Inductance trip is initiated. See the details of this trip for the inductances required. Generally the q axis inductance falls as the q axis current is increased, i.e. the motor is loaded. While low speed operation is active the drive will apply a current limit defined by Low Speed Sensorless Mode Current (05.071) to prevent the q axis inductance from falling to a level that would cause the motor to become non-salient. It will be necessary to limit the bandwidth of the speed controller to a level of 10Hz or less for stable operation particularly at low speeds. Provided these conditions are met this method can be used in the same way as control with position feedback, but the control performance is limited.

1: Non-salient
If the motor has low or no saliency (i.e. the conditions defined for Inductance cannot be met under the required load conditions) then this method can be used for low speed operation. This mode does not provide the same level of control as injection mode and the following should be considered:

1. Only speed control can be used when low speed mode operation is active.
2. When the low speed algorithm is active it will not be possible to produce more than approximately 60% to 70% of rated torque. Low Speed Sensorless Mode Current (05.071) defines a current applied in the motor d axis to aid starting. A value of 20% is suitable for most motors with a load of up to 60% rated torque. However, in some applications this level may need to be adjusted.
3. There may be some movement of the motor shaft in either direction as the motor starts.
4. It is not possible to measure the motor inertia using auto-tuning with Auto-tune (05.012) = 4.
5. Normally the ramp rate should not be slower than 5s/1000rpm when operating in the region below Rated Speed (05.008) / 10.
6. This mode is not intended to control the motor for prolonged periods at low speed, but is intended to allow the motor to be started from standstill to run outside the low speed region.
7. This mode is not intended to allow motor reversals. If the direction does need to be reversed, the motor should be stopped and any oscillations must die away, before the motor is restarted in the other direction.
8. When this mode becomes active during deceleration from the normal operation there can be a relatively high level of negative q axis current. If the over-current trip level has been reduced then this unexpected level of current can cause spurious over-current trips. This can be prevented by ensuring that Regenerating Current Limit (04.006) is set at a suffciently low level.

2: Current
This method, which applies a rotating current vector at the frequency defined by the speed reference, can be used with any motor with no saliency or moderate saliency. It should only be used with motors where more of the torque is produced in conjunction with the magnet flux rather than from saliency torque. This mode does not provide the same level of control at low speed as injection mode, but is easier to set up and more flexible than "Non-salient" mode. The following should be considered:

1. Only speed control can be used when low speed mode operation is active.
2. A current specified by Low Speed Sensorless Mode Current (05.071) is applied when low speed mode is active. This current should be sufficient to start the motor with the highest expected load. If the motor has some saliency with no-load applied, and a suitable saturation characteristic, the drive can detect the rotor position and apply the current at the correct angle to avoid starting transient. If the motor is non-salient as defined by the conditions for Inductance trip then the drive will not attempt to detect the rotor position and the current will be applied at an arbitrary angle. This could cause a starting transient if the level of current applied is high, and so Low Speed Sensorless Mode Current (05.071) should not be set to a higher level than necessary. To minimise the movement as a result of applying the current, it is increased over the period defined by Sensorless Mode Current Ramp (05.063) in the form of a squared characteristic (i.e. it is increased with a low rate of change at the beginning and the rate of change is gradually increased).
3. It is not possible to measure the motor inertia using auto-tuning with Auto-tune (05.012) = 4.
4. As the level of current when low speed mode is active is not dependent on the applied load, but is as defined by Low Speed Sensorless Mode Current (05.071), and so the motor may become too hot if low speed mode is active for a prolonged period of time.
5. Generally Low Speed Sensorless Mode Current (05.071) should be set to a level higher than the expected maximum load, and can be set to a much higher level than the load if the saliency and saturation characteristic allow the position of the rotor to be detected on starting. However, Low Speed Sensorless Mode Current (05.071) should be matched more closely to the expected load under the following conditions: the load inertia is high compared to the motor interia, or there is very little damping/loss in the load system, or where the q axis inductance of the motor changes significantly with load.

3: Current no test
The "Current" method is used, but no attempt is made to determine the position of the rotor before applying the current. This can be selected for example, if the motor does not have a suitable saturation characteristic to allow the rotor position to be determined during starting, or if faster starting is required. The initial current vector angle will be at an arbitary position with respect to the actual rotor position. As the vector sweeps round it must make the rotor start to rotate. If the ramp rate is too high the rotor may not keep up with the current vector and the motor may not start. If this is the case then the ramp rate should be reduced and/or the current used to start the motor should be increased.

4: Current step
The current starting modes normally provide a smooth transition between the low speed current mode and normal running at higher speeds. If the drive accelerates very rapidly and only spends short periods of time in each mode the transition smoothing can malfunction. "Current step" mode is similar to "Current no test" mode except that the transition smoothing is disabled. It is not advisable to use this mode unless it is necessary as torque transients will occur when changing between low speed and normal running operation.

5: Current only
The "Current" method is used, but no attempt is made to determine the position of the rotor before applying the current. The system remains in this starting mode at all speeds and does not change to the normal operating algorithms. This provides a very basic open-loop control method, that is not recommended for most applications. Flux weakning is not possible, and so this method will not operate correctly when the motor voltage approaches the maximum voltage avaialble from the drive.

The current applied to the motor is always the level defined by Low Speed Sensorless Mode Current (05.071) and the frequency is defined by the frequency reference. The following should be noted:

1. It is possible that the motor may become unstable especially on light load.
2. The current in the motor will always be at the level defined by Low Speed Sensorless Mode Current (05.071) whatever the load. Care should be taken not to overheat the motor.
3. The speed feedback provided is derived from the reference, and so it does not necessarily represent the actual speed of the motor.

Parameter | 05.065 Saliency Torque Control Select
--- | ---
Short description | Set the required saliency torque control mode
Mode | RFC‑S
Minimum | 0 | Maximum | 3
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Disabled
1 | Low
2 | High
3 | Auto

Most permanent magnet motors include some saliency due to saturation and physical construction. Torque is normally produced by interaction between the magnet flux and the stator current, but any saliency can be exploited to produce additional torque, which can increase the torque per amp produced by the motor. If Saliency Torque Control Select (05.065) = 0 (disabled) torque is only produced from the magnet flux. If Saliency Torque Control Select (05.065) = 3 (auto) then torque can be produced from saliency and the mode to do this is selected automatically based on the value of Rated Torque Angle (05.089). If the torque produced by the magnet flux is more than twice the torque produced by saliency under rated conditions then Rated Torque Angle (05.089) < 30o, and under these conditions low saliency mode is selected, otherwise high saliency mode is selected. It is possible to specifically choose the saliency mode, Saliency Torque Control Select (05.065) = 1 gives low saliency mode and Saliency Torque Control Select (05.065) = 2 gives high saliency mode. It should be noted that if Rated Torque Angle (05.089) = 0 that the saliency mode remains disabled. Active Saliency Torque Mode (05.066) shows which mode is active.

Low saliency mode is for motors where a majority of the torque is produced from magnet flux, and high saliency mode is for motors where signficant torque is produced from saliency. The following are affected by the mode used:

1. At higher speeds there is a limit on the amount of torque that can be produced by the motor for a given motor terminal voltage. Different algorithms are used to impose this limit depending on which mode is selected. The method used with low saliency mode can be enabled or disabled depending on the setting of Enable High Speed Mode (05.022).
2. Different methods are used during flux weakening at higher speeds to control the motor.
3. Different sensorless control algorithms are used. The parameters required for the sensorless algorithms are similar execept for the q axis inductance when the motor is operating on load. See No-load Lq (05.072) for more details.

Parameter | 05.066 Active Saliency Torque Mode
--- | ---
Short description | Active Saliency Torque Mode
Mode | RFC‑S
Minimum | 0 | Maximum | 2
Default |  | Units |
Type | 8 Bit Volatile | Update Rate | Background Write
Display Format | Standard | Decimal Places | 0
Coding | RO, TE, ND, NC, PT

Value | Text
0 | Disabled
1 | Low
2 | High

Active Saliency Torque Mode (05.066) shows which saliency torque control mode is active. See Saliency Torque Control Select (05.065) for more details.

Parameter | 05.067 Over-current Trip Level as Percentage Kc
--- | ---
Short description | Over-current trip level as a percentage of Kc
Mode | RFC‑S
Minimum | 0 | Maximum | 100
Default | 0 | Units | %
Type | 8 Bit User Save | Update Rate | Background Read When Drive Not Active
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

The drive provides an over-current trip to disable the inverter quickly if the instantaneous current from the drive exceeds a specific level. This trip is provided to protect the drive in case a short circuit is applied to the outputs, but it also prevents the current into the motor from exceeding a specific maximum level. If Over-current Trip Level as Percentage Kc (05.067) and Over-current Trip Level as Percentage of Rated Current (05.069) are left at their default values of zero then the default over-current trip level is used (which is provided to protect the drive) and is set to the maximum possible safe level of current. The trip occurs when the r.m.s. output current corresponds to Full Scale Current Kc (11.061) (plus a margin for cable charging currents with smaller drives). The instantaneous trip level is √2 times the r.m.s. level. Unless there is a reason to limit the peak current in the motor further then these parameters should be left at their default values.

If Over-current Trip Level as Percentage of Rated Current (05.069) is set to a non-zero value it defines the over-current trip level as a percentage of the rated current (where the rated current is defined by Rated Current (05.007) or M2 Rated Current (21.007)). If Over-current Trip Level as Percentage of Rated Current (05.069) is non-zero then Over-current Trip Level as Percentage Kc (05.067) has no effect. The actual setting of the over-current trip in the hardware is relatively coarse, and so the trip level may be less than the selected setting. For this reason Actual Over-current Trip Level (05.068) shows the actual trip level as a percentage of rated current when Over-current Trip Level as Percentage of Rated Current (05.069) is used to define the trip level. As the over-current trip is normally reduced to protect a motor, using Over-current Trip Level as Percentage of Rated Current (05.069) to define this is the preferred method.

If required, the over-current trip level can be set as a percentage of Full Scale Current Kc (11.061) using Over-current Trip Level as Percentage Kc (05.067). Again due to the coarse setting in the drive hardware the actual over-current trip level may be less than the required level, and so Actual Over-current Trip Level (05.068) shows the actual trip level as a percentage of Full Scale Current Kc (11.061) when Over-current Trip Level as Percentage Kc (05.067) is used to define this. Either a value of zero should be used, so that the default level is applied (assuming Over-current Trip Level as Percentage of Rated Current (05.069) = 0) or a value from 10% to 100% should be used to define the level as a percentage of Kc. (Note there are settings from 1 to 9 which are only provided for legacy reasons and should not normally be used where the percentage is given by (Over-current Trip Level as Percentage Kc (05.067) + 1) x 10%.)

It should be noted that if the over-current trip level is reduced, it may be necessary to reduce the current limits from their default levels so that the maximum controllable current in the drive does not exceed the over-current trip level during normal operation, or else spurious trips will be produced.

Parameter | 05.068 Actual Over-current Trip Level
--- | ---
Short description | Actual Over-current Trip Level
Mode | RFC‑S
Minimum | 0 | Maximum | 500
Default |  | Units | %
Type | 16 Bit Volatile | Update Rate | Background Write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT, BU

See Over-current Trip Level as Percentage Kc (05.067).

Parameter | 05.069 Over-current Trip Level as Percentage of Rated Current
--- | ---
Short description | Over-current trip level as a percentage of rated current
Mode | RFC‑S
Minimum | 0 | Maximum | 1000
Default | 0 | Units | %
Type | 16 Bit User Save | Update Rate | Background Read When Drive Not Active
Display Format | Standard | Decimal Places | 0
Coding | RW

If this parameter has a non-zero value it overrides Over-current Trip Level as Percentage Kc (05.067) and the over-current trip level is calculated as a percentage of the motor rated current. See Over-current Trip Level as Percentage Kc (05.067) for more details. For some drive derivatives the default for Over-current Trip Level as Percentage of Rated Current (05.069) is non-zero. If this is the case, the lower level has been provided to protect motors where the demagnetisation level is relatively low. Before increasing this parameter the maximum allowed motor current MUST be checked to ensure that the over-current trip level is not above this level or else the motor may be PERMANENTLY DAMAGED.

Parameter | 05.070 Inverted Saturation Characteristic
--- | ---
Short description | The motor has an inverted saturation characteristic
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW

The change of motor inductance with flux producing current is used to determine the flux direction in RFC-S mode when operating without position feedback. Normally an increase in flux producing current reduces Ld because the motor becomes more saturated. For some motors increasing the flux producing current can modify the flux path and Ld increases with increased flux producing current. For normal motors Inverted Saturation Characteristic (05.070) should be left at its default value of zero, however, for motors with an apparent inverse saturation characteristic Inverted Saturation Characteristic (05.070) should be set to one. If this parameter is not set and the motor has an inverted saturation characteristic this can be seen as follows:

1. Sudden jump in position during a stationary auto-tune with position feedback.
2. Sudden jump in position during auto-tuning in sensorless mode.
3. Very unstable operation or the motor runs in the wrong direction on starting in sensorless mode.

It should be noted that the saturation characteristic is also used to locate the flux axis when performing a stationary auto-tune or when measuring the phasing angle on enable. If a motor has an inverted saturation characteristic then Inverted Saturation Characteristic (05.070) should be set to one for these tests to operate correctly.

Parameter | 05.071 Low Speed Sensorless Mode Current
--- | ---
Short description | Maximum current limit for low speed injection mode or magnetising current for low speed non-salient mode
Mode | RFC‑S
Minimum | 0.0 | Maximum | 1000.0
Default | 100.0 | Units | %
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW, RA

See RFC Low Speed Mode (05.064).

Parameter | 05.072 No-load Lq
--- | ---
Short description | q axis inductance with no motor current
Mode | RFC‑S
Minimum | 0.000 | Maximum | 500.000
Default | 0.000 | Units | mH
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 3
Coding | RW, RA

The q axis inductance can vary significantly with the level of d and q axis current in the motor. The drive estimates a value of Lq for use by the control system as the levels of d and q axis current change and writes this to Estimated Lq (05.088) as shown below.

In all cases, except for the value of Lq used in estimating the rotor position for sensorless control of high saliency motors (i.e. Active Saliency Torque Mode (05.066) = 2), the normal (chord) q axis inductance is used and the value shown in Estimated Lq (05.088) is the normal inductance defined by the level of current in the motor. The following description shows how Lq is estimated except when sensorless control is being used for a high saliency motor. The q axis inductance is assumed to vary with id and iq on a flat plane where three points on the plane are defined by No-load Lq (05.072), Lq At The Defined Iq Current (05.078) and Lq At The Defined Id Current (05.084). The current levels that correspond to these points are (Id=0 Iq=0), (Id=0 Iq= q Axis Current For Inductance Values With Current (05.075)) and (Id= d Axis Current For Inductance Values With Current (05.082)) respectively. No-load Lq (05.072) should be set to the correct value or measured using auto-tuning. Lq is calculated as follows depending on how many of the other parameters required to calculate Lq are also set up. The current levels are set as a percentage of the motor rated current (Rated Current (05.007)).

Parameters changed from default | Parameters left at default | Action
None | q Axis Current For Inductance Values With Current (05.075) and Lq At The Defined Iq Current (05.078) and d Axis Current For Inductance Values With Current (05.082) and Lq At The Defined Id Current (05.084) | Lq At The Defined Iq Current (05.078) is assumed to be 80% of No-load Lq (05.072). Lq varies with Iq using this value of inductance and q Axis Current For Inductance Values With Current (05.075) = 100%. No change of Lq with Id.
q Axis Current For Inductance Values With Current (05.075) | Lq At The Defined Iq Current (05.078) and d Axis Current For Inductance Values With Current (05.082) and Lq At The Defined Id Current (05.084) | Lq At The Defined Iq Current (05.078) is assumed to be 80% of No-load Lq (05.072). Lq varies with Iq using this value of inductance and q Axis Current For Inductance Values With Current (05.075). No change of Lq with Id.
q Axis Current For Inductance Values With Current (05.075) and Lq At The Defined Iq Current (05.078) | d Axis Current For Inductance Values With Current (05.082) and Lq At The Defined Id Current (05.084) | Lq At The Defined Id Current (05.084) and q Axis Current For Inductance Values With Current (05.075) are used to defined Lq. No change of Lq with Id.
q Axis Current For Inductance Values With Current (05.075) and Lq At The Defined Iq Current (05.078) and Lq At The Defined Id Current (05.084) and | d Axis Current For Inductance Values With Current (05.082) | Lq At The Defined Id Current (05.084), q Axis Current For Inductance Values With Current (05.075) and Lq At The Defined Id Current (05.084) are used to defined Lq with d Axis Current For Inductance Values With Current (05.082)=-100%.
q Axis Current For Inductance Values With Current (05.075) and Lq At The Defined Iq Current (05.078) and d Axis Current For Inductance Values With Current (05.082) and Lq At The Defined Id Current (05.084) | None | Lq At The Defined Id Current (05.084), q Axis Current For Inductance Values With Current (05.075), Lq At The Defined Id Current (05.084) and d Axis Current For Inductance Values With Current (05.082) are used to defined Lq.

If sensorless mode is being used to control a high saliency motor the rotor position is estimated using the incremental inductance of the motor and Estimated Lq (05.088) shows the value of the q axis incremental inductance instead of the normal inductance. The system to calculate this is the same as for the normal inductance except that Lq Incremental Inductance At Defined Iq Current (05.079) is used instead of Lq At The Defined Iq Current (05.078), and Lq Incremental Inductance At Defined Id Current (05.085) is used instead of Lq At The Defined Id Current (05.084). Note that for all other functions in the drive the normal inductances are used.

No-load Lq (05.072) is used as described in the table below.

Function | Details
High performance current control | If high performance current control is selected (Current Controller Mode (04.030) =1) Lq is used by the controller in q axis.
Low speed operation with sensorless control | If injection mode is used (RFC Low Speed Mode (05.064) = 0) for low speed operation Lq defines the gain of the system.
*Control above low speeds with sensorless control | No-load Lq is used in the system that actively calculates the value of Lq with changing motor currents which is used to calculate the rotor position.
*Motor torque limit | No-load Lq (and not the dynamically calculated Lq) is used to define the torque limit of high saliency motors.
*Rated torque angle | If the drive defines Rated Torque Angle (05.089) no-load Lq is used in the calculation.

The following parameters are also used in the system that calculates the value of Lq with different levels of motor current, and so these also affect the functions marked with * in the table: q Axis Current For Inductance Values With Current (05.075), Lq At The Defined Iq Current (05.078), Lq Incremental Inductance At Defined Iq Current (05.079), d Axis Current For Inductance Values With Current (05.082), Lq At The Defined Id Current (05.084) and Lq Incremental Inductance At Defined Id Current (05.085).

Parameter | 05.075 q Axis Current For Inductance Values With Current
--- | ---
Short description | q axis current level corresponding to the inductance values with current
Mode | RFC‑S
Minimum | 0 | Maximum | 200
Default | 100 | Units | %
Type | 8 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

See No-load Lq (05.072).

Parameter | 05.077 Phase Offset At Defined Iq Current
--- | ---
Short description | Defines the change in electrical angle between the point of minimum inductance around the motor as load is applied
Mode | RFC‑S
Minimum | -90.0 | Maximum | 90.0
Default | 0.0 | Units | °
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW, RA

Phase Offset At Defined Iq Current (05.077) defines the offset of the point of minimum inductance as an electrical angle from the point with no current in the motor to the point with a level of Iq equivalent to q Axis Current For Inductance Values With Current (05.075). When the value is left at its default value of zero no compensation for phase offset with changes in Iq are made. Phase Offset At Defined Iq Current (05.077) is used for low speed RFC sensorless control using injection mode. A positive value advances the point of minimum inductance with positve Iq. See RFC Low Speed Mode (05.064). For most motors a value of zero is acceptable.

Parameter | 05.078 Lq At The Defined Iq Current
--- | ---
Short description | q axis inductance at the defined Iq current for the inductance values
Mode | RFC‑S
Minimum | 0.000 | Maximum | 500.000
Default | 0.000 | Units | mH
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 3
Coding | RW, RA

See No-load Lq (05.072).

Parameter | 05.079 Lq Incremental Inductance At Defined Iq Current
--- | ---
Short description | q axis incremental inductance at the defined Iq current for the inductance values
Mode | RFC‑S
Minimum | 0.000 | Maximum | 500.000
Default | 0.000 | Units | mH
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 3
Coding | RW, RA

See No-load Lq (05.072).

Parameter | 05.082 d Axis Current For Inductance Values With Current
--- | ---
Short description | d axis current level corresponding to the inductance values with current
Mode | RFC‑S
Minimum | -100 | Maximum | 0
Default | -100 | Units | %
Type | 8 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW

See No-load Lq (05.072).

Parameter | 05.084 Lq At The Defined Id Current
--- | ---
Short description | q axis inductance at the defined Id current for the inductance values
Mode | RFC‑S
Minimum | 0.000 | Maximum | 500.000
Default | 0.000 | Units | mH
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 3
Coding | RW, RA

See No-load Lq (05.072).

Parameter | 05.085 Lq Incremental Inductance At Defined Id Current
--- | ---
Short description | q axis incremental inductance at the defined Id current for the inductance values
Mode | RFC‑S
Minimum | 0.000 | Maximum | 500.000
Default | 0.000 | Units | mH
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 3
Coding | RW, RA

See No-load Lq (05.072).

Parameter | 05.087 User Defined Rated Torque Angle
--- | ---
Short description | User defined rated torque angle which will override the drive auto-calculated value.
Mode | RFC‑S
Minimum | 0 | Maximum | 90
Default | 0 | Units | °
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

Rated Torque Angle (05.089) defines the amount of torque and flux producing current required to give maximum torque from the motor with rated current (i.e. Rated Current (05.007)) including any torque produced from saliency. The torque angle is the angle between the q axis of the motor and the current vector required to produce the torque. This is also referred to as the current angle or phase advance angle. If Saliency Torque Control Select (05.065) ≥ 1 the drive will try and exploit the saliency torque of the motor by applying some negative d axis current. If User Defined Rated Torque Angle (05.087) is changed from its default value of zero and Saliency Torque Control Select (05.065) ≥ 1, the value entered in User Defined Rated Torque Angle (05.087) is written directly to Rated Torque Angle (05.089) and defines the angle used for the applied current from the q axis. As the torque angle is increased the amount of negative d axis current increases. This angle should be set to the level to give maximum torque per Amp with rated current in the motor.

It is possible for the drive to automatically calculate the rated torque angle from motor set-up parameters and those measured during autotuning. The drive will calculate and set up Rated Torque Angle (05.089) if Saliency Torque Control Select (05.065) ≥ 1 and User Defined Rated Torque Angle (05.087) = 0. The following parameters are used in the calculation:

Rated Current (05.007)
Ld (05.024)
No-load Lq (05.072)
Volts Per 1000rpm (05.033)
q Axis Current For Inductance Values With Current (05.075)
Lq At The Defined Iq Current (05.078)*
d Axis Current For Inductance Values With Current (05.082)
Lq At The Defined Id Current (05.084)*

*The value of Lq used in the calculation is the value estimated using the same algorithm when the drive is running. See No-load Lq (05.072) for the effect of leaving these parameters at their default values.

Parameter | 05.088 Estimated Lq
--- | ---
Short description | Estimated value of Lq including the effects of Id and Iq
Mode | RFC‑S
Minimum | 0.000 | Maximum | 500.000
Default |  | Units | mH
Type | 32 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 3
Coding | RO, FI, ND, NC, PT

Estimated Lq (05.088) shows the calculated value of Lq. See No-load Lq (05.072).

Parameter | 05.089 Rated Torque Angle
--- | ---
Short description | Rated Torque Angle
Mode | RFC‑S
Minimum | 0 | Maximum | 90
Default |  | Units | °
Type | 8 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

See User Defined Rated Torque Angle (05.087).