A.1.8 Tuning the position loop for a torque servo drive

The MintDrive can be tuned as a torque servo drive, passing the profiled demand components through the position and current loops only. To do this the MintDrive keyword CONFIG should be set to 6 by typing:

CONFIG=6

You should have already tuned the current loop and speed loop, but in this mode of operation the speed loop gains are disregarded. The value of KPROP should be set to a small value when operating the controller as a torque servo drive - a starting value of 0.5 is suggested.

Increase KVEL until the motor shaft becomes stiff to turn. Use WorkBench to perform test moves and monitor results. If KVEL is increased too much, instability will occur.

Typically, KVELFF is found to be close to KVEL when operating the controller as a torque servo drive, so set KVELFF to the same value as KVEL.

Values for the terms KINT, KDERIV and KACCEL can be found by applying the principles for tuning the motor as servo drive. See section A.1.7 on page 102.

A.1.9 Saving tuning information

The speed loop and current loop gains are stored in the controller’s battery backed memory, but the position loop gains are not. It is recommended that all of these parameter settings are placed in your application’s Configuration file so that the MintDrive can be re-configured after each power-cycle or if it is replaced.

105

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Baldor MN1274 06/2001 Tuning the position loop for a torque servo drive, Saving tuning information, 105, CONFIG=6