Hi, I am using NUCLEO-F401RE development board with X-NUCLEO-IHM07M1 (MCSDK v6.2.1) to run FOC algorithm to control SM-PMSM low inductance motor with 1 pole pair. While tuning it I found out strange thing about Ia, Ib currents. First I saw it when I did Kp and Ki tuning of current regulator. As you recommended I changed start-up table like this:
Final speed | Final torque | Duration, ms
0 2.0A 0
0 2.0A 100
0 1.0A 0
0 1.0A 100
0 0.0A 0
and recorded Ia current with rotor fixed and Id Kp=0 and Ki=0. It looked like this
Then I changed start-up table like this
Final speed | Final torque | Duration, ms
0 2.3A 0
0 2.3A 100
0 1.0A 0
0 1.0A 100
0 0.0A 0
and made the same recording, it had some distortions in this case
I don't understand why it happens. According to data sheet X-NUCLEO-IHM07M1 board has 2.8 A output peak current. And also when motor load increases the following happens. Algorithm sets maximum torque (2.8A) but Ia and Ib currents get distorted, you can see it in the following screenshot. Then speed feedback error appears and motor stops.
Why does this distortion happens? (all tests were done at 32V bus voltage)
Thanks
