2025-04-15 2:20 AM
Hello,
I am using the STEAVL-PTOOL4A to drive a BLDC motor using the FOC with hall sensors. The motor is running ok but I noticed that during the start of the motor, the speed does not reach its final value at the same time. I mean there is a noticed difference. Sometimes it is slow, sometimes it is fast. I increase the bootstrap Capacitor time from 10ms to 1000ms I still have some differences but lower when I had 10ms.
Here are some plots when the speed reaches its target fast
And here when it is slow:
I took the Valfa and Vbeta since it could be related to the Capacitor voltage. So I noticed as if the startup of the capacitor does not have the same duration.
Could someone explain why I have this behavior?
Thank you