routing done! It's going to be a 4 layer board, which can reduce noise by a factor of 10. I'm using layer 2 for the control ground, since all the paths are on the top surface, which makes for an itsy bitsy loop area. I've changed a lot. I'm taking the EVTech list's advice for this one. No experimental correction of turn-on times. I'm just going to match the parts as best I can, and then monitor the current going through each igbt individually, which each igbt hooked up to its own hardware overcurrent protection. There's also desaturation detection, but just for all 3 as a single big IGBT, rather than 3 separate desat detection circuits.
It's just a single control board/driver board that will plug into the 3 IGBTs with female spade connectors that are soldered directly to the control board. There's one PWM signal that goes right to the gate of each IGBT, at which time there's a buffer circuit that can do 15 amps per IGBT.
It also has capacitors right at the gate to emitter, so that the loop area is way smaller than I've ever had it. Also, there are back to back zeners right at each gate to emitter spade connector. If it blows up, then I'll just go home and cry, because it's the best I can do. haha.
Oh heck ya! The UPS truck is coming!
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