NOMADICISTA

Saw a few sites where people had built there own motor controller and was looking for a site that had schematics so I could build my own.

Anyone got a clue?

My, that's a very ambitious project. I have used the National Semiconductor LM3425 regulating pulse width modulator as the core of a simple controller for my electric tractor. It's a one-chip PWM controller and can be set up in a variety of configurations and can employ current limiting, etc.

Here's the link to the National datasheet page, which includes sample circuits: http://www.national.com/pf/LM/LM3524D.html

In practical aplication, you'll need to couple the output of the chip to a bank of paralleled N-channel MOSFET's to handle the motor's current.

http://www.jstraubel.com/944EV/EVproject.htm

Half way down, home made motor controller with large caps.

I sent him an email asking if he had the schematics but no response yet. I'd love to save a few hundred dollars making my own

After reading the website, the controller he made uses 6 IGBT modules @ $312 a pop and 4 diode modules at $104 a pop. that's $2288 for the main pieces and you still need to buy the caps, processor and various other parts to get a working controller

That Curtis 1231C is looking mighty good to me at this point; $1500 and I get a working controller.

Dude; Even the books on designing a PWM controller are expensive!