MC Observer + Cordic

[ktim]

I am trying to operate an 8-pole pair 48V PMSM motor with

• STEVAL-CTM009V1
• IHM09M2
• Nucleo-G431RB

Sensorless with Observer + Cordic. I have run a motor profile with EVALSTDRIVE101. I have entered the parameters for the motor in MC Workbench 6.3.1. I have set the Startup Rev-Up procedure and it starts most of the time, but when it switches from Rev-Up to Observer (Start to RUN) the motor does not turn further. It starts to wobble between two coils.

The motor is in free rotation without a load.

Can someone give me a hint on what i have to change?

Thanks in advance

 

[cedric H]

Hello @ktim ,

If your motor ran smoothly during the profiling, I would advise you to use the STO-PLL instead of STO-CORDIC. It is the one used when you configure your project to generate the profiler binary.

Regards

Cedric

[ktim]

Hello @cedric H ,

Thank you very much for your reply.

After I profiled the motor, I saved the configuration from the profiler and imported it into the workbench. I set it up with Observer + PLL, generated it and loaded it into the controller. When I run it with Motor Pilot, it never goes further than rev-up and ends with a startup error. Changing the ramp does not help. I have also tried the hints that are displayed by clicking on the error type. Do you have any other advice?

[ktim]

Hello @cedric H,

I've got it working now. The calculated values of the Observer+PLL are completely different from what works. The values the profiler worked with are close to the calculated values. Is there a routine I can use to fine tune the observer values?