Paul & Sabrina's cheap DIY 144v motor controller

[MPaulHolmes]

Is the RPM +/- 150, or is it consistently below or consistently above by 150? Or is it consistently below or consistently above by some value that's proportional to the rpm? Like at 500rpm, it reads 25 too high, 2500 it's 125 too high..?

Assuming the pin is free, I could do an input capture based rpm for more accuracy. I did that in the BMS, where there were 8 different input capture pins all listening to changes to their ports. It was interrupt driven, and would construct 0's and 1's based on the times each input capture pin would stay at 0.

Happy St. Patricks day to you too!!!!! My great grandpa would force my grandma to wear orange on St. Patricks day since he was british.

[MPaulHolmes]

I added the push-pull feature in the software so that if a couple pins stop going high and low at 16kHz, the hardware will disable the mosfet driver, since that would most likely happen if the microcontroller crashes. It was just a single line of code that's required to run at 16kHz, so it eats up almost no processing power. I was going to add a "microcontroller_crashed_fault in the code", until I realized, the micro wouldn't know if the micro crashed! hahaha.

I also added programmable max current. the variable is called max-current. haha. You can input anything you want in the range 0-9999 real life amps. That means if you set it to 120, full throttle will be 120 amps. I double checked all the pins to make sure everything is good.

The controller is 99.9% done:


It's 6 isolated supplies, so 6 separate pwm signals that all have their own shielded twisted pair (with ground) cable going right to the input of the respective optocoupler.

I think someone was asking about the schematics. I'll post everything once it's all working. The wiki is seriously jacked up right now though. It's been taken over by a weird spam-bot.

I've got an updated schematic and layout that removes the VERY EXPENSIVE DC-DC converter (like almost $18) which feeds the inputs to the 6 line filters, and replaces it with a homemade DC-DC based on the very popular MC34063

The careful observer will note that it costs like $0.63 cents. hahaha. The rest of the nick-nacks you need to make it work are another $2-$3 or so.

[dave koller]

HAPPY ST. PATTY'S DAY.... ()

[bennelson]

I did some more experimenting with the laser cutter, working my way towards making a kick-butt case for my controller.

See the update in THIS THREAD.

-Ben

[jackbauer]

Paul , I'm not too sure if the error is consistent. I have my limiter set at 3500 rpm and it will kick the power off somewhere between 3500 and 3700. Good enough for gov work. If you can make it better then great. Btw when are these super cool new control boards going to be available to the masses? My secret sepex controller project could really use one!

[MPaulHolmes]

I just found an error on the one-off board. The input "L1" filter pins were messed up. But I noticed that you don't use L1 sometimes, without too much trouble as a result, so I just did what I saw you did for this one. Just use wire to connect the 2 sides, but the wire had to make an x-shape because of the messed up pins. So far everything else seems to be working, but I'm checking all the little details, and am breadboarding a prototype of the little DC-DC that cuts off around $15 from the cost. so it will be very very soon! Like in a couple days I'm going to order it.

[jackbauer]

Yeh I wasn't able to find that filter from a supplier over here. Just linked it out. Never had a problem.

[sawickm]

Originally Posted by MPaulHolmes

I think someone was asking about the schematics. I'll post everything once it's all working. The wiki is seriously jacked up right now though. It's been taken over by a weird spam-bot. I've got an updated schematic and layout that removes the VERY EXPENSIVE DC-DC converter

Hi Paul,

Great work as usual !!!

Just email your files to me when you finish them.

I can upload your schematics to the protected file server that has all the ReVolt stuff on it. Then I will add their link to the Ecomodder wiki after the Spam-bot stuff is fixed.

I also have the PCB files for the IGBT driver interface, I want to add that to the Ecomodder wiki too.

-Mark

[isaac_alaska]

Originally Posted by jackbauer

Paul , I'm not too sure if the error is consistent. I have my limiter set at 3500 rpm and it will kick the power off somewhere between 3500 and 3700. Good enough for gov work. If you can make it better then great. Btw when are these super cool new control boards going to be available to the masses? My secret sepex controller project could really use one!

what happens when it hits the rev limit? does it completely cut the power for a certain time? or can it reduce the throttle so that power is still applied but it doesn't go over the limit?

[jackbauer]

Power is cut till the motor drops 250rpm below the limit. If you just floor the throttle in neutral it sorta bounces off the rev limiter like an ICE.