Strange current waveform driving a BLDC motor using the IHM08M1 with the Nucleo F303

[der.ule]

I keep investigating why I have problems driving my motor with negative speeds.

I captured the phase voltage directly on the motor leads (yellow, cyan and magenta channels) and the current on the DAC output (Ia or Ib) and I noticed this peaks on the current waveform.

 

Zooming in, the currents themselves don't look bad at all

 

However I do not understand where does peaks are coming from

Any ideas will be greatly appreciated.

[MK.1]

The picture in the manual contradicts what is written.

[der.ule]

Oh my .. ! I was totally blinded by the 120° of the Hall Sensor, that I did not stop an think about the whole picture, thanks a lot for that. I will test out next week and see how it goes.

[der_ule]

After a lot of testing (different problem but same parameter search) and re-reading the thread that you linked before.

I believe that the correct angle should be around 120°.

I annotated the pic posted by @Dario CUCCHI​ for the case where the hall sequence is H1, H2 and H3 according to his text:

As you can see now measuring from the maximum of the B-emf induced on phase A to the first rising edge of signal H1 I get 120° as in the previous case: and this the value to be set in the "Placement electrical angle".

 

Following his instructions, I annotated my capture too and calculated an angle of around 120° as you can see.

still, thanks a lot for your help and pointing me in the correct direction (several times) :thumbs_up:

[MK.1]

that's right, it's my carelessness)