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Motor will stop after ramp p

QuirinS
Associate III


[PN]: custom Board based on evspin32g4-dual
[VERSION]: 6.4.0

[Motor]: Xing2207 1800Kv

[CubeMx]:6.14.1

Hello,

I have a problem with getting my FOC BLDC motor to start, the specs of the motor are: 0,08Ohm 50uH 0,32Vrms/kRPM. My project is for two sensorless motors with one shunt each, but I am trying to get started with the one connected directly to the stspin32G4.

When using 10kHz Pwm the motor first vibrates but does not spin, then it starts accelerating, then I get the startup failure. The failure always occurs when it reaches the start-up speed threshold. When I try 40kHz PWM it wont start at all. I noticed that in cubeMX there are some errors.

The schematic for the mosfet drivers is identical to the evspin32g4-dual:

33Ohm gate resistors and 1uF Boot Cap

I set the Boot charge time to 50ms and the Charging Duty cycle to 15%

 

Screenshot 2026-03-17 181420.png

Below is a screenshot of the startup phase once the motor is running, orange: one phase, blue: voltage over shunt, the digital signals are the gates of all three phases. Why are the phases not shifted 120 degrees?

Screenshot 2026-03-17 180627.png

How do I align the motor at startup, as I cant find the option?

Are those errors in CubeMx (picture below) critical?

 
 
 

Screenshot 2026-03-17 181250.png

 Thanks for your help!!!!

 

1 REPLY 1
GMA
ST Employee

Hello @QuirinS,

For error description and management, refer to the documentation available through Workbench tool > About > Documentations > Documentation > User manual tab, (FOC) firmware errors link.

Are you using the 6-step algorithm for expecting 120-degree phase shift? Refer to the User manual, Six-step firmware algorithm chapter.

STM32CubeMX warnings are not critical.

If you agree with the answer, please accept it by clicking on 'Accept as solution'.
Best regards.
GMA