Quote:
Originally Posted by MPaulHolmes
Hey! I got the pwm working on the dsPIC! It's running 6 at the same time in complementary mode. In other words, 3 are running independent of each other, while the other 3 are the NOT of those 3. And dead time is built in! I can use that chip for synchronous rectification! It's perfect for it. Soon(ish) I'm going to order like 20 of those new 230amp 200v mosfets, and use them for freewheel mosfets and regular mosfets. I'm not sure about how much dead time to build in, but the default from the Application Note AN908 is 0.000002 seconds, so I'm using that right now. Derating it 1/2 allows for over 1000 amps. The voltage spikes at that current level should be around 25 volts, so it should still be fine at 144v nominal. I've also got Bob Woolery's 1000amp shunt in my hot little mits. Thanks, Bob! Another alternative is to split M- into 2, and just measure 1 of them with the LEM.
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Paul,
I'll check the surplus place near here that has big a** current shunts.
They had 2000 amp shunts the last time I was there, but the stock
changes often, so I'll see if I can check next week.
Is the bare board and programmed mcu available?
I'm ready to order 2 of each!
Thanks
Mark