Friday, February 22, 2008
The prototype controller is almost ready for serious testing! The snow has prevented me from going down the Radio Shack to purchase the final parts for the current limiting circuit and IGBT driver. The IGBT requires a dedicated driving circuit, whereas the MOSFETS were fine running of the 555 timer chip. I am building two seperate motor drive sections, the IGBT veriosn and MOSFET version. I am curious to see which one is more efficient. The MOSFETS are easier to control, but the IGBT is much more easy to place in a package.
This simple prototype is running at a mere 2KHz so it's quite audible, but I am figuring out how to increase this to 15kHz, but so far no luck. I hope to have a few PIC controllers, but I have no idea when or if the free samples will come in.
Friday, February 15, 2008
Controller Parts- Pretty much all the guts are on the way
500 AMP Shunt
Probably some other things I can't think of.
I ordered up a PB5 throttle because I don't really have the time to make one out of the 5K Radio Shack potentiometer. I know how to do it, but getting the parts and machining them is a bit too much for me since I am building the controller.
I am also considering increasing my voltage to 96 volts since the new parts for my controller will take it, and my K99 would be happiest at that voltage. Calculations also show that at that voltage, the Wally World batteries would work fine getting my back and forth to school, with charging at school for maximum battery life.
Wednesday, February 13, 2008
Lets get to my picture. I have my K99-4007 on the table on the right my PWM circuit and MOSFETs on the table on the left, my 5K pot throttle on the wood stump and at the bottom, my ancient crappy 12 Volt Deep Cycle that has barely enough life leftto run this test. I only have 10 of my 20 MOSFETs hooked up since this is a basic test.