Getting past Under voltage fault to start motor with EVSPIN32F02Q1S1. May be a bug.

[Muthanna]

Hi,

I had been using the older version of MCW w/ Monitor to use an STEVAL-ESC001V1.

I got a new 30Pole BLDC to test out. Since the board does not support Hall Sensors I had hacked some test points and pads to pull out leads, re-configure the "Digital I/O" to use Hall Sensors. It works fine, has been working for other motors too.👍

I used this board (STEVAL-ESC001V1) to save a Profile of the Motor using ST Motor Profiler.

I then switched connectors to my connect to my new EVSPIN32F02Q1S1 and upgraded to MCSDK_v5.Y.2 which has ST Motor Pilot.

I noticed that I still cannot use EVSPIN32F02Q1S1 to Profile the motor as it's not available on the ST Motor Profiler.

At first I had it configured for using Hall Sensors. The code generation was smooth.

At first I got error that PWM frequency was too high (default 30,000 Hz (EVSPIN32F251) )

I reduced it to 16KHz

The ST Motor Pilot connected smoothly and was a displaying real time speed of the rotor.

Trial 1: The motor failed to start with "FOC Duration", so I changed execution rate to 2

Trail 2,3,4..... : The motor fails to start with under voltage fault.

I could not Debug this

I then started another project for sensor-less control. (To mitigate hall sensor complication)

I was ready to face the start-up algorithm tweaks. I also noticed it started smoothly during motor profiling.

At first I got error that PWM frequency was too high (default 30,000 Hz (EVSPIN32F251) )

I reduced it to 16KHz

Code size was too big, needed to optimize for size.

Motor Pilot did not show speed of motor this time.

Trial 1: The motor failed to start with "FOC Duration", so I changed execution rate to 2

Trail 2,3,4,5,6,7,8.....: The motor fails to start with under voltage fault.

The Bus Voltage is 24V which is accurately measured and displayed on the Motor Pilot UI

The Bus Voltage Configuration is as follows

Min Bus Voltage = 21 V

Max Bus Voltage = 26 V

Nominal Bus Voltage = 23 V

I probed the Bus on my DSO to look for transient voltage drops. But nothing like that is happening.

Basically everything appears normal on the Motor Pilot with no faults.

When I click on the ON button or use the on board switch, there is a brief electrical noise in the motor but it does not rotate and the controller stops with an "Under Voltage" Fault. Which I acknowledge and try again.

I just cannot get past this problem. I'm not able to debug. I need help.

Not able to connect to https://my.st.com/ols

Thanks in advance.

[Laurent Ca...]

Dear @Muthanna​ 

I just come back from holidays.

Whar are the last news about your issues?

Best regards

[Muthanna]

Quite some time.

We found multiple solutions to overcome the issue.

Firstly, we were making a mistake in the JP6,7,8,10 for selecting when we switched between sensor less and hall sensor.

Second, we later identified noise in the Hall Sensor signal when we probed it.

the 10pf filter C37,38,39 isn't sufficient to filter the noise.

Even though we changed it. we found the RC Parallel filter is not of much use.

The series 1.8k resistor could work, but the Pull Up comes between the RC Configuration.

We solved it by breaking JP2 and adding external pull up before J3 connector.

I suggest changes to bring in with Low Pass filter for Hall sensor inputs. and correction in User Manual2836 Table 1 JP9

Thanks,