DIY IGBT Motor Controller

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Upgrade from my first video: http://www.youtube.com/watch?v=iU0KLyCgTHk

Again a 1 quadrant PWM motor controller, made from IGBTs instead of MOSFETs. Also, the upgraded motor - both for my go-kart project.

See my blog at will-ev.blogspot.com

For people asking for schematics - for now I won't provide one, maybe when I have time.
It's really simple. Two "single" IGBTs - one used as a switch, which connects Motor- to Battery-; the other as a freewheeling diode from Motor+ to Motor-.
An IGBT snubber (blue) across the switching IGBT - just a ~0.6uF 600V cap, there are more complicated ones but you have to choose those more carefully.
A capacitor bank across Battery+ and Battery- made with electrolytics (~30mF) and polypropylene (~5uF) and one $12 MLC ceramic cap (designed for switching power supply). Get yourself an IGBT driver, but I used a MOSFET driver instead - takes 5V PWM from microcontroller and outputs huge currents to quickly charge/discharge the IGBT 0 to 15V. (really should be -5 to 15V but I was lazy)
All the high current paths must be low inductance. Notice the amount of copper I used!
Oh, lastly connect Motor+ to Battery+ to complete the circuit. So, when IGBT is ON, current flows B+ to M+, through motor to M-, through switching IGBT to B-. When IGBT is off, the current flows from M- through freewheeling diode to M+. As in, it continues to flow through the motor in its original direction through the motor from M+ to M- because of its inductance (and possibly because it's generating too).
Use this thread for learning: http://ecomodder.com/forum/showthread.php/paul-sabrinas-cheap-diy-144v-motor-controller-6404.html#post78198
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