Details on GM controllers.

[Arlo1]

Hi I'm interested in finding out more details on the large controllers.   I need to know things like the PWM frequency and if possible what type of commutation.  They use.   Any details would be appreciated I have a hard to drive motor...  Its 8uH inductance and .009 ohms resistance from phase to phase and cheep controllers melt down when trying to run this motor.  I would like to run as much phase current as possible ~700-900 peak phase amps and 500-600 continuous with 100+ volts I have been working on building my own controller and have had success at 84v and 350 phase amps but I can not build one as cheep as the GM controllers and if these controllers will run this motor then others will buy this as well.

[Bikemad]

Hi Arlo:
Welcome to the group

If you want to push 60-80 KW into a motor, and want to do it cheaply, you need to decide which desire is more important to you.  Us old hot rodders know that how fast you can go is largely determined by how much money you want to spend.  By the way, that is a pretty impressive goal.  What are you planning to do with all that power!  I think you already know it might be possible to  replace the output FETs in a cheap controller with an array of VERY high power FETs in parallel. The infineon based controllers are doing that now, but nowhere near your power output figures.   It would seem you already are doing some pretty impressive power outputs.  What are you using for driving and for heat sinking your current output FETs?  Could we see a photo of your controller,  battery, etc?

[Arlo1]

Hi I have built a few controllers the one that works was putting 20kw into the system and I was getting 15 hp at the rear wheel.
I ask PWM frequency and algorithm questions because I have a hard to drive motor and Its a prototype.  If they sell this motor it will cost a lot for me to build controllers as I am not good at setting up a factory in China to do it all for me. 
I had had success with 20khz and as low as 14 kHz Center aligned PWM which its like having 2x normal PWM with old six step commutation.
I would be interested in testing a GM controller if I new it had a chance of running this motor.
Here is a test video of the bike when I had it only at 9.6 RWHP
http://www.youtube.com/watch?v=91pGd7jOgB4
And here is a little description of it yes its nasty and the next generation of my controller is almost finished and should be 15-20 kw continuous and 30 peak!  http://www.youtube.com/watch?v=lstpPHkFKyw

[Arlo1]

So I guess no body knows the fine details of the bigger GM controllers?

[Andrew]

>>>>>>>Swooosh>>>>> >      Way over my head