No Holding Torque with FOC + Current Loop Appears Unresponsive
Hello,
I am generating firmware using MCSDK 6.4.0 and testing my motor with Motor Pilot. I am using FOC with encoder feedback.
Under no-load conditions, the velocity control loop works perfectly with the default PI gains, the motor tracks speed very accurately. However, the motor produces no holding torque and can be stalled easily with just my fingers at all speeds.
I assumed this was due to a poorly tuned current loop, so I began increasing the proportional gain of the torque (Iq) PI controller in Motor Pilot while running in torque mode. During testing, I monitored the I_Q_MEAS and I_Q_REF registers while gradually increasing the torque current.
There is quite a bit of noise in the I_Q_MEAS signal, but it is still clear that it never steps anywhere near I_Q_REF. Increasing the torque gain has no noticeable effect, the motor still pulls only a small amount of current, and the holding torque remains nonexistent.
I have been searching for any hidden current limit or clamp that could explain this behavior, but I have not found anything yet.
I am using the EVLSERVO1 drive.
I would appreciate any insight or suggestions.
Thanks,
Isaac