Sensorless motor Control with mc workbench: Why does motor go to full speed right after start up and to desired speed some seconds later?

[FMaur.1]

Hello,

I am driving a motor using the STEVAL-SPIN3201. The code is generated via the mc workbench.

When I test the programm, the motor behaves like that:

The motor starts up slowly according to the start up procedure I chose in the workbench.

Then suddenly the motor moves with fullspeed for some seconds.

After this the motor slowes down to the desired speed. Now I am able to change this speed via the motor pilot.

When I change the Kp and Ki value, I can reduce the duration of the "full speed periode". However, it is still there.

Can you explain what is happening and why the motor moves to full speed for a short time?

Thanks a lot for your help!

Florian

[Cristiana SCARAMEL]

Since your question is about STM32 MCSDK, I added STM32 Motor Control topic.