Paul & Sabrina's cheap DIY 144v motor controller

[MPaulHolmes]

I think your grammar is excellent! I have no trouble understanding you. Thank you so much for writing! Your work is absolutely beautiful! I'm sure I'll have questions! How did you get such tight fitting and perfect drilling? What sort of equipment are you using?

[struja]

MPaulHolmes

My coutroller is not 100% finished it's more like 89%
You are building your controller with microcontroller for brain ? Are you planing to put temp. monitoring and stuff like this or is it just for the PWM ?

The main diferent between your and mine is that mine is made with just ~100$. It's cheap and very simple , it's based on SG3525 ( for PWM ) , bd139/140 ( for sig.amp. ) , irfp450 ( for power grup x6 ) and for dides byv72ew200 x4 .
In a video it didn't have capacitor ( only one from power supply ) I'm putting few in there ! All electronics are electricaly isolated from the aluminiun box but they aren't thermal isolated !!

[MPaulHolmes]

$100!!! That's awesome!!!!!!! You are very talented. That's going to be a great controller. I saw your motor cycle. Very nice! What tools did you use to make such a beautiful box???!!! It was amazing!

That's the nice thing about a metal box is the heat can get out! hehe. My controller has an ATMega8 for PWM and monitoring throttle position, current, and temperature. Later I'll add a sensor to limit motor RPM too. I had an extra A/D channel I wasn't using, so why not? And it's only about an extra $5 to do it. Current limiting is also implemented in hardware. The hardware sends a signal to the microcontroller that the mosfet driver has been disabled. The microcontroller then waits for the current to come back under 500 amps, and then re-enables the mosfet driver.

I fixed a few mistakes in the program. I tested everything in the simulator, and it all seems to work very well. I think it's ready to put on the chip. Now all I need to do is finish the breadboard of the control circuit to test it out. Well, I also need to finish the dang box. It's getting close!

[MPaulHolmes]

I mostly finished the box. It will work best I think with the heat sink down rather than up. Now I just need to add 4 holes on maybe the M- side? For 12v+, 12v-, and 2 wires for 5k pot.

[krispyllama]

All these chips and extra parts are making it a little hard to follow. Just got internet back (just moved to a new house). Took some time while at work to catch up.

Paul, you program these chips using C, is there any good source you can suggest for someone like myself to get into the language? I used to use QBasic way back and jumped to visual studio 6.0. So basic is about all I know. I have been out some time but want to get back into things. The project looks great. Also you mentioned that you can get double sided 4oz copper boards would that mean 2oz per side or 8 total ozs? I can't wait till Ben gets his hands on this. Seeing the union of the best guys in the ev scene will be great. Will we be seeing them metro tired smoking? I'm sure we will.

Keep up the good work guys. I'm learning so much from you all.

[MPaulHolmes]

I'm pretty sure that 2 sided 4 ounce copper means 4 ounce copper on each side. I got some 3 ounce double sided PCB and it is 3 ounce on each side.

Hmm... A good book on C? Microcontroller programming is quite a bit simpler in a sense than regular programming. Any basic C tutorial on loops, if..then statements, and bit operations would be fine for micro-controller programming. This looked like a pretty good place:

C tutorial! ya!

[krispyllama]

Thanks for the quick reply and link. I'm still stuck guarding this place till 11 so I have lots of time on my hands and will read up. I tend to think too deeply when programming so I'm sure ill do the same with these chips. I think I alreayd have the basics figured out like the physical pins are just variables that can be read via the program. At least that's how I would design a chip. I was very comfortable learning assembly language several years ago but writing a program with that in your head can give one a migrain esp if the program is as complex as yours. Well ill stop bugging you and let you get back to work. Also great pics. Makes me want to get back into modding I have 2 ccfl lights with the 12volt driver if you ever want to pimp out the box lol ones blue and ones red, gives a nice wash with a purple mid-range. Just say the word and its yours.

[esoneson]

Beauty, Paul, real beauty!

[MetroMPG]

I agree - that box is awesome, Paul. I'd definitely want to show off my controller like that!

--

Oh - congrats on winning the "Mod of the Month" contest for projects active in Feb 2009: http://ecomodder.com/forum/showthrea...onth-7325.html !

[MPaulHolmes]

We won??!! Yahoo!!!!!!!! I can't wait for the free t-shirt! I'm so excited!!! Go Paul, It's your birthday, light a candle, throw a party!