Alignment of interior permanent magnet motor

in the example ( https://in.mathworks.com/help/sps/ug/ipmsm-torque-based-load-control.html )

I am trying to align motor to zero degree by giving Idref 100A, Iqref 0A and electrical theta zero degree.

Observed phase current as linear, But RPM is oscillating, why?

I shared the folder link for reference.

https://drive.mathworks.com/sharing/409b8611-5e69-4505-a997-f85b98915bdd

Answer 1

[Sabin]

It is not possible to drive the PIMSM in this way (torque control and no load). The rotor will slip and oscillate around zero. You will need to spin the rotor the rotor to desired speed using an external velocity source or a load-based algorithm, or another motor in speed control mode on the same shaft that will provide the load.

Check out this example of torque control using an external velocity source:

https://www.mathworks.com/help/sps/ug/ipmsm-torque-control.html

Check out this example for an electric engine dyno setup:

https://www.mathworks.com/help/sps/ug/electric-engine-dyno.html