Paul and Sabrina's Cheap 3 Phase Inverter (AC Controller) with Field Oriented Control - Page 13 - Fuel Economy, Hypermiling, EcoModding News and Forum

TheSGC · 12-02-2009, 09:42 PM

I have kind of been watching this thread, but that is changing soon. I have received my new Zilla, and once my transmission woes are dealt with that will be in and my Kelly out.

And here is the AC related goods- one of my professors has offered to trade a complete Solectria AC system for my Kelly!

I will be getting a Solectria ACgtx20 motor and a controller, if he can piece it together. His son was one of the original Solectria employees and he has a garage full of Solectria AC parts used for repairs, so he wants to trade for my unused Kelly.

On Monday I will get to see the goods, and hopefully it will have a fully functioning Solectria controller. If not, guess what I will be building....

etc · 12-02-2009, 11:52 PM

To Paul, I have an inside connection at the Baldor motor plant. He deals with all of the surplus motors, inverters, and controllers. What are the ideal specs for the motor are you looking to use? I may be able to donate to the cause and would love to help anyway I could.

Brian

jackbauer · 12-03-2009, 11:52 AM

IGBTs on the way!

dcb · 12-03-2009, 12:15 PM

the 6MBI450U4-120s? That was nice Jack I'm not sure I trust myself with 1200v and 450 amps

jackbauer · 12-03-2009, 02:53 PM

No these are some fuji 150a 600v parts i had. I'm using a 1600v 1000amp igbt in my dc controller

vinny1989 · 12-03-2009, 03:28 PM

Stupid question time:

What voltage would be needed for the AC controller? i mean, i assume it runs on DC 12V, but what battery pack is needed?.. 96v? 144v? more?

jackbauer · 12-03-2009, 05:14 PM

It depends on the motor used. For example a 415v delta connected 3 phase industrial motor would require a dc bus of around 700v

There are ways around that problem and i suspect its something we will be looking at in greater detail as the project progresses.

MPaulHolmes · 12-03-2009, 09:13 PM

EDIT: THANKS JACK!

Also, you can run a motor at any voltage, but it just won't have the same top end RPM. It can have the same low RPM torque though, which is just related to the current. That's what Fran was telling me. I've never experimented with 3 phase motors before.

I have mostly been busy with work this week, but have also been reading about how to generate the pwm signals that will give the rotating magnetic field. It's not bad at all. It all comes down to projecting the 3 phase currents onto the complex plane, and finding their vector sum, and projecting that sum onto the real and complex axes. It sounds sort of confusing, but it's not bad, I promise!

I'm going to try programming the pwm for a basic rotation in the next few days and control it with a V/freq = const and then make the step to FOC. Its a big change from lighting leds though

jackbauer · 12-04-2009, 03:28 AM

No.........not complex numbers........i ...........j omega .............nooooooo arrrgghhh

TheSGC · 12-04-2009, 10:03 AM

I have just reread the whole thread, and I was wondering if anyone has actually found any EV-friendly AC motors out there?

Next week I should be getting my Solectria bounty and I can see what they are made out of and post it here. The Solectria inverters actually use MOSFETs and are known to blow up during regen when the batteries are full.