Good day,
my design uses an externally powered STSPIN32G4, so that the CPU can be powered while VM is off.
Once VM is present the fault flags (mainly MC_UNDER_VOLT) can be reset and the motor can be started. The motor control will go through it’s initialization state and finally end up in the RUN state. However, this does NOT reset the embedded gate driver chip, so this will still be in an undervoltage fault state. Therefore, the power will never be powered. Yet, the fault will be cleared implicitly by stopping the motor and then starting it again.
In my application, where I use the FOC with just an incremental encoder, this can have some dangerous side effects. Since the control relies on the alignment between encoder and the motor, having the motor de-energized during the alignment phase will cause a wrong alignment. However, the SDK remembers that the motor has already be aligned. If the motor is stopped now and then restarted (which implicitly clears the gate driver faults) the motor will go straight to the RUN state and thus be in RUN with improper alignment. This will cause undefined behavior of the motor, including speeding up way beyond the maximum speed.
My proposed solution to this is to also clear the gate driver faults or potentially reinitializing the gate driver when acknowledging the faults.
MCSDK Version: 6.2.0
STM32 FW: 1.30
Cheers,
D.Frejek
