Other Parts Discussed in Thread: DRV8301
Hi,
I damaged the DRV8301 IC in field weakening zone.
I am running the controller with a battery. While testing in field weakening, the BMS cut-off the battery due to some fault and that led to probable overvoltage due to high back-emf and the driver ic got damaged (FETs are still good). I could not capture the waveform though. I am worried if I need to add any protection circuit. I have read many papers on it and here are a few possibilities:
1. Turn all the lower FETs on and that will short circuit the back-emf.
a. Since the current would only be limited by motor resistance, will the motor come to a stop all of a sudden? I cannot allow that on my bike.
b. Also, my motor resistance is very less - 10mohms. In that case, the current will be very high and it may even damage the FETs? What care I should take?
2. Add a resistor to discharge the DC-Link Cap in case of overvoltage condition. However, I do not prefer this method and I am looking for a better option.
3. In case of fault on BMS side, turn off only the discharge path and keep the charge path on. In that case, the current will continue to go to the battery and save the voltage. But this may possibly damage the batteries if they are already fully charged.
Is there any other method? I would like to know your comments on the above points in case if I am wrong or missing something.
