The primary issue I'm facing is that I'm experiencing over current fault whenever I try to start the motor, and I'm not sure what is causing it.

[CKors.1]

The motor I'm using does not have Hall Effect sensors or encoders. What I'm confused about is what could cause an over current error. I'd like to note that for the motor I'm using, I do not know the specific values of certain parameters, such as the number of pole pairs. What specific motor parameters would influence the likelihood of an over current error? Are there any start up parameters or drive settings that could influence it as well? I'd like to note that any settings that I have not attached here were untouched. The only motor parameters I had changed were the number of pole pairs, the nominal current, the resistance, and the B-emf constant, keeping in mind that these numbers are not necessarily accurate. I also changed the final current ramp value and current final ramp value in the start up parameters, and the PWM frequency and execution rate (since apparently the ratio between the two must be less than 14k). I'd like to know what values could be causing the over current error, if any, and what drive settings, start up parameters, or other settings should be changed based on the motor parameters I have attached.

[Laurent Ca...]

Dear @CKors.1​

Could you give a little bit more details about the motor you use?

Best regards

[CKors.1]

Hello,

The motor I'm using is a drone motor made by betafpv. The link to them is here: https://betafpv.com/products/1805-brushless-motors

Unfortunately, there isn't any documentation available about the motor itself. With that being said, we are fairly confident that it has 6 pole pairs. In our motor parameters, we estimate the correct nominal current and resistance. We are fairly confident of our back-emf parameter though. Please let me know if there's any additional information about the motor that you need and I'll try my best to answer.

Thank you

[GMA]

Hello,

Did you try the ST "Motor Profiler" provided with the workbench?

It gives some hints in order to evaluate pole pairs value e.g. and it estimates other motor characteristics.

May be that the "Nominal Current" value is too high...

If profiling fails, iterates with lower profiler "Max Current" values.

Best regards.

[CKors.1]

Hello,

I have the motor profiler, but I'm unsure how to add the board I'm using to it. I have the STEVAL-SPIN3202 Inverter board, which as I understand, is essentially both a power board and control board in one. On the Motor Profiler software, the STEVAL-SPIN3202 board does not show up. I can only search for power boards and control boards. Any ideas as to how to get around this?

[GMA]

Hello,

You are right, motor profiler is not available on ST-SPIN boards. At least, you can open a motor profiler (with a set of available boards), by clicking on "How to detect..." box, it will give you a way to determine pair pole number as you are not sure of it.

On the other hand, did you try by decreasing the motor "Nominal Current" value?

[CKors.1]

We did try decreasing the Nominal Current value, but it didn't solve the issue. We are also pretty confident that our motor has 6 pole pairs.

I was able to turn off over current protection entirely, and while that solved the overcurrent problem, I ran into a start-up failure error. The motor would move a few clicks in either direction and then stop. It was very strange. If I adjusted the position of the motor before restarting the "start motor" command, sometimes it would spin slightly more. In various starting positions, the motor would either spin several clicks, almost a full revolution, or not at all. The direction also appeared to be random as well.

It seemed to be a commutation problem, though I'm not sure where to go from here. Any help would be appreciated.