Peaks during Current Regulator Step‑Response Test (MC Workbench Tuning)

[ElGuerrero91]

Hi everyone,

I am currently testing the Current Regulator Step Response as described in the ST Motor Control documentation.
I do get the sharp edges, but I see short peaks/overshoot in the current waveform.

 

 

Setup:

• Custom Board → EVSPIN32G4 has been taken as reference

• Step‑test configured exactly as in the document

• 3‑shunt topology

• PWM frequency: 20 kHz

• BLDC Motor 

• Motor Control Part3 - Troubleshooting and fine tuning_v2.pdf - Google Drive

 

What could be the reason for the peaks? 

 

[AScha.3]

Hi,

Typical measuring problem: you some induced magnetic - > voltage spike. 

Try better points for ground at the probe, maybe even the usual ground clip connection is too long, so need these ground spring at the probe.

And check for any ground loop with the scope and its connection to mains ground.