Hey guys, this is my first post here but I've been a long time lurker. I had a question about what you might use to drive a 3 phase motor with an Arduino. I have a few UNOs right now, but I have a feeling this project will call for a bigger Arduino with more I/O. I'm not new to coding/Arduino projects, but I've never played around with motor control before and I'm having a hard time finding a proper controller. I looked on hobby king and a couple other sites, but I'm not exactly sure what I need. Basically here's the project, I have a rear steering axle with a 12 volt 3 phase 80 amp electric motor. There's hall sensors for the motor position, and a dedicated sensor for the rear wheel position. I'm looking for a controller that will allow me to hold the motor in one position as well as being able to reverse the direction, will that need to be a special controller, or will any 100 amp 3 phase controller work? Could you list any good ones? Thanks in advance!
What max/min frequencies are you dealing with?
Paul
PS.. You are describing a servo motor not a regular 3-phase AC motor.
Take a deep dive in the theory of driving 3 face motors from a DC source.
There are such controllers for 24 and 48 volts used in f ex electric forklift trucks. If You have a really big wallet.....
That description sounds entirely bizarre!
You need to give us the Web link for (all) the device(s) in question before we can figure out what you are actually trying to say! 
The 50 amp servo motor on my VW Jetta does exactly what the OP described.
Paul
Hi,
Welcome to the forum.
Please read the post at the start of any forum , entitled "How to use this Forum".
OR
http://forum.arduino.cc/index.php/topic,148850.0.html.
I have a rear steering axle with a 12 volt 3 phase 80 amp electric motor.
What does the motor do, drive the axle for drive or steer the axle for direction?
Is the motor output shaft geared?
Can you please post a picture of the setup and a link to data/specs of the motor?
Thanks.. Tom.. 
you might start by seeing if an 80 amp BLDC controller is what you need. should be around $99 USD.
if that works, then a simple UNO should be able to drive the thing as it would have a separate micro-controller on-board. you just send speed and direction signals.
Hey guys, thanks for the quick responses and sorry for the delayed reply, I've been pretty swamped the past couple days. I did read how to use this forum, but sometimes I get a little ahead of myself and assume people just know what I'm talking about. I'm not sure the min/max frequencies, but I almost figured I might want a servo driver, since I thought 3 phase was usually A/C. It's a discontinued gm Quadrasteer axle from the early 2000s the motor is just for driving a planetary gearset which steers the rack, and specs aren't really available from what I've found. Tom, I'm sure I have a pic I can dig up, give me a few minutes. I figured just driving the motor wouldn't use much I/O, but the Arduino will need to read a vehicle class 2 data line, a steering wheel position sensor, control the motor driver, and read at least the dedicated position sensor, likely the hall sensors too. Sorry if that was kind of hard to read, I'm trying to reply to all comments so far
Paul__B:
That description sounds entirely bizarre!You need to give us the Web link for (all) the device(s) in question before we can figure out what you are actually trying to say!
I would supply links/specs if there were any, this is a defunct axle from almost 20 years ago now. I can link to a gm pdf, but there's really no info on the motor in it, also how do I upload pictures, do I have to host them elsewhere and llink to them? https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.denalitrucks.com/documents/QSteer%2520training.pdf&ved=2ahUKEwi7iMuBj5ztAhVXZc0KHbVcCp8QFjAAegQIBRAC&usg=AOvVaw2KKGkcNL-VdvQ38enPQbci is the link to the pdf, there's an okay picture of the motor on page 2-22. If you don't want to follow the link, you can Google Quadrasteer training, and it'll be the link to denali trucks.
Edited because I fat fingered the link url
Did you go talk to a local GM truck dealer or truck repair shop to see what documents they have? Do they still repair the device? 20 years is not that long for a truck.
Paul
Paul_KD7HB:
Did you go talk to a local GM truck dealer or truck repair shop to see what documents they have? Do they still repair the device? 20 years is not that long for a truck.Paul
I haven't, but that's a good idea. The issue with these axles is that gm and all parts suppliers washed their hands of them about 10 years ago, not long after finishing the short (4-5 year production cycle). Most anything to do with these axles (sensor, tie rod boots, control module, motor, etc...) Has been NLA for almost 10 years now. Gm dealers don't even seem to like doing alignments on them anymore from what I've read. There have been a wave of people reproducing parts for them the last year or so, but there are a couple things left, the main one being the control module, and I'd like to try my hand at it; I think the control aspect of it is within my abilities, I just have no idea if I need a special kind of motor driver, or if any brushless dc motor driver that will handle the current will do
Then get one of the controllers and try to reverse engineer it. Most of the components may be house numbers that will be hard to track down.
Paul
Paul_KD7HB:
Then get one of the controllers and try to reverse engineer it. Most of the components may be house numbers that will be hard to track down.Paul
I have a functional controller I'm attempting to reverse engineer, but I don't want to dig into it, since all of the components are potted in resin, and it'd practically have to be destroyed. I also don't think tearing it apart would further my search for a motor driver, since as you said, most parts will probably be in house part numbers