I'm working on an EV project right now. Kind of like an electric skateboard (mebbe with a removable seat, haven’t decided), but much bigger, heavier, and more dangerous. Fun stuff.
Anyway, it started with me buying some Kollmorgens off of eBay. It has since taken only vague shape, and probably will not be completed for a while (namely until I get me a decent MIG welder, or a friend of mine lets me use his). Right now it consists of little more than some motors, batteries (still need more), and various connectors. The sheet metal and other raw materials I should get in a while.
With the four Kollmorgens I plan to put in it it should put out about 1600 watts. While this is quite a bit of power to play with, I do plan on racing this thing. I want to use an external controller with the Kollmorgens. This poses a bit of a problem, mostly on how to go about it. I could just buy a brushless controller, but I really don't want to spend that much money, especially because I might need two.
Option two is rather more difficult. I could keep the motor controller intact and use the phase outputs and hall wires to drive higher power components. This would almost undoubtedly require I use voltage regulators so I don't fry the brains of the controller, not to mention getting a lot of FETs to replace the stock ones. However if the old FETs (I haven’t taken out any of the potted controllers to spec out the parts) can handle more than they are being used for, this might not be too much of a problem. Seems unlikely that they could, but if someone could tell me for sure, that would be great. I think this might be the most wallet-friendly solution, so I'll be trying it out on a extra motor just to find out.
My last idea is a little more exotic but I like the concept: If I could find a chip that would take the signal from the hall sensors and use it to drive some FETs, I could essentially make it work just like a brushed motor, and use a PWM controller to control the speed. However, I don't have the slightest idea where to find such a chip. I have seen a few that do this, however they are basically the entire controller on a chip, and therefore more expensive. In addition, I will certainly be messing with the voltage input, and if the chip and the FETs will not accept a (really) wide voltage range, the whole idea falls apart.
Basically, I need a few ideas (and possibly instructions) on how to go about converting the Kollmorgens to external control.
If anyone can help me with finding some useful parts (chips, controllers, FETs, etc.) I would really appreciate it. I'm not a electronics supergenius, but I do have a fair bit of experience with this sort of thing. More than the average Joe, at least.
P.S. What would you guys recommend as the max power rating on these motors? Could they handle 2,000 watts? I can attach the things to a water cooling system, so heat isn't really a problem, but I don't want the magnets cracking or anything.