ARKEL Elektrik Elektronik Ltd.
Ş
ti. www.arkel.com.tr
08.2012
ADrive
61
3.5 – Anti-Rollback position controller
(Disabled / Enabled)
This function is used only for closed loop applications.
After the mechanical brake is released a rollback may occur because the motor has not yet
developed enough torque to hold the car. The car may move up or down depending on the load
balance. This effect is most noticeable with gearless motors because of a low friction. The anti-
rollback function is used to help prevent rollback on elevators.
Mechanical brake release point is considered as reference point. Unwanted movements to
the left or right side from this point will be stopped by applying force to contrary direction with
position controller.
Anti-rollback position controller gains are determined by the parameters 3.6 and 3.7.
Increasing the gains will cause more quick response to rollback. Reducing the gains will cause
late response. Too high gain values can lead noisy and instable start-up. Too low gain values
cause an appreciable rollback in car. See section “20.4 Improving start-ups” for appropriate Anti-
Rollback settings.
3.6- Anti-Rollback position controller Kp gain
(KP_ARB: 10 – 2000)
The Kp gain of Anti-rollback position controller.
3.7- Anti-Rollback position controller Kd gain
(KD_ARB: 10 – 2000)
The Kd gain of Anti-rollback position controller.
3.9- Encoder filter
(Enc_Filter: 1-4)
The filter applied to the encoder value.
1: 2 ms
2: 4 ms
3: 8 ms
4: 16 ms
It is recommended to set this parameter to 2 for closed-loop asynchronous motors and to 2
or 3 for synchronous motors.
3.10- Dynamic filter
(Disabled / Enabled)
In synchronous motors, as the rpm of the motor is low, it may be necessary to use an
encoder filter level of 3 or 4. Increasing the filtering level allows a more precise reading of speed
but on the other hand delays the reading speed. Selecting dynamic filtering will allow
compensation of these delays.