Dear Friends and TI Engineers,
Currently, I do some research on PMSM FOC. I buy the TMDSHVMTRPFCKIT development kit from TI last month and I used 2HP PMSM motor with an incremental encoder 2500 PPR.
I have some difficulties regarding rotor position calibration. Based on the explanation from the ControlSuite, if we want to lock the rotor into d-axis, we can set the Iq=0 and Id=some constant value then the rotor will move a little to align with the d-axis. This step happened when I did this step, but sometimes not. I guess this is depend on the first rotor position (if it is not, please correct me). Now, I only able to rotate the motor in 100rpm. The motor will stalled if the speed is over than 100rpm.
The problems :
1. does it happened because of the position not calibrated?
2. how to know the rotor position has already align with the d-axis from the code/watch windows?it said on the application note that when the first index signal is detected by the QEP, the QPOSILAT latches the angle offset in between initial rotor position and encoder index. How to get the offset angle?
3. on the application note also writen CALIBRATION ANGLE= OFFSET ANGLE +- n.LINE ENCODER. what is n.LINE ENCODER? on the code from ControlSuite, the default calibration angle value is 1000 for 2500 PPR encoder. do i need to change the calibration angle value each time the program is restart?
Can anybody give me some help regarding my problems? I'm still learning about PMSM FOC control.
Thank you~
