As soon as I get a little free time, I'm going to try multiple gate drives and learn the AT90PWM3b micro, which was designed for synchronous rectification. Then eventually I'm going to take about 12-15 of the new fancier 230amp 200v mosfets, and do a synchronous rectification version, so the freewheel mosfets will have way more current carrying capacity than what I'm using now. I think that one will do 1000 amps. I'll need maybe 6 or 8 ounce PCB, and I'll need to do something tricky with the LEM current sensor, since it can only go up to 900 amps. That one may only be safe at 132v or so, since the inductive voltage spikes get bigger with large di/dt, and it's already cutting it sort of close to 200v with the 144v nominal inductive voltage spikes.
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