Quote:
Originally Posted by johnsiddle
Paul, was there a particular reason you used one mosfet driver instead of ten (apart from cost).
I have copied your power board using ten drivers and ten 130A 200V Mosfets and just had a spectacular blow up.
Also when your current sensor trips does it cut the motor drive and return as soon as the current drops or is there a delay or something? I think mine created a strong juddering effect just before blowing up.
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More isn't always better. having multip MOSFET drivers increases the chance of them being out of sync from each other turning switches on off microseconds before or after each other. Paul used one MOSFET driver because that was all that was needed to drive all of the MOSFETs. The total gate charge of all ten MOSFETs is still less than limit on one driver.
the controller turns turn on off extremely quickly when current limiting. The motor actually makes like a groaning noise and switching on and off only a few hundred times a second. What you feel is probably individual MOSFET blowing up.
Adam