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So, I ordered all the parts for a prototype SR control board. There's a lot to do! milling a new tiny board for the surface mount current sensor, since the LEM can only go up to 900 amps (but isn't linear all the way up there I think). Then I have to figure out the correct distance for the new Melexis current sensor to sit above the board. I'm thinking it will be about 1/4" above the pcb, since the 7mT one had to sit 0.75" above, and this one is good to about 25mT of range. That would be 4 pieces of PCB.
I need to test the SR software, and Adam had a good idea with that. I'll just use an IGBT! The dead time will probably be larger than with the mosfets, as they are harder to turn on and off, or so I hear, but we'll see. Dead time is just a variable in the code. Oh no, I have to change a whole number. hahaha.
I'm thinking that the SR controller's main strength won't be that it will use so much less heat by replacing th ediodes with mosfets, but rather replacing the 60amp freewheel diodes with 230 amp freewheel mosfets. Oh heck ya. I also need to figure out how low of a gate resistor I can get away with, with each driver driving 5 of the gigamos mosfets. It will be interesting to see how heating works. derating to 50% would be 1150 amps. I can't wait to see how they perform. I have 25 of them just sitting in the garage waiting to be tested!
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