We ran these with 3 phase inverters. Many years ago I worked on diesel electric locomotives that were DC traction motors. I don't see a reason to deviate from the 3 phase approach, for a number of reasons. The biggest being the availablity of proven technology at production costs. We must recognize however, the contribution that the automotive industry has made in advances on many basic designs. With that in mind, I'm sure that the multi phase motor is poised for redesign to service a specific application.

The Diesel-electric locomotives today have switched to three phase drives.

 

That is one heck of a PM, the weight to power is great, is it possible to over volt a PM or AC motor like the DC motors to increase power output? On a series DC motor you can double the rated voltage with out mods and with some mods you can go x3 or higher for short periods of time like 0 to 60mph.

you can, to some extent. It's all about heat dissipation, and insulation ratings. On the other end of the scale, you would reduce voltage to control excessive currents on low speeds. All in all, dependability dictates sizing the motor to the application.

Don't forget that esculating currents equate to lowering efficiencies.

 

The Diesel-electric locomotives today have switched to three phase drives.

Quite a few years ago. I suspect the only reason that DC is used in automotive is the availability of parts, and the realative ease of implementation.

 

you can, to some extent. It's all about heat dissipation, and insulation ratings. On the other end of the scale, you would reduce voltage to control excessive currents on low speeds. All in all, dependability dictates sizing the motor to the application.
Don't forget that esculating currents equate to lowering efficiencies.

Your right, this was for drag racing (read short motor life) The motor was a 9.1 inch, 96 volt, 19hp, series wound DC motor and I was running it at 336 volts and 1200 amps for 17 seconds. I had lots of twisted and burnt parts. I love smoke

A couple of years ago I caught a hydrogen fuel cell vehicle on fire, I ran out of adrenalin running I still have the part for that one and I'm keeping it. The safeties work and the vehicle was repairable.

 

I hate you guy's As if I didn't spend enough time on the Web! Now you got me back into this. To quote Michael Corleone "Just when I thought I was out... they pull me back in."

All of the new non-hybrid EV's are AC motor driven according to the sites I've been reading. Here's a few more good sites;

http://evauthority.com/dc-vs-ac-electric-car-motors/

http://electric-vehicles-cars-bikes.blogspot.com/2009/10/ac-versus-dc-electric-car-motors.html

http://evalbum.com/motor