[proee]

The advancement of motor and power convert technology is also worth noting. AC motors are a huge upgrade over the old dc motors that used brushes.

[frankus]

AC motors are really great if you're building a drivetrain from scratch. You get a cheaper gearbox (single speed, no reverse) and a cheaper motor (theoretically) by paying for roughly six times the electronics (although you can divide the current capability of everything by the square root of three). And it drives just like an automatic transmission, only better.

But with a conversion vehicle the gearbox comes for free with the donor car, and it's typically more work to integrate a single-speed drive than to just adapt the motor housing and shaft to the transmission bellhousing and flywheel. And you're not paying the early adopter tax that's still present on AC drivetrains.

[happenstance]

DC motors are very efficient, so, I'd have to see some numbers to buy that.

Also, a big plus for DC motors is that the controllers are simpler. AC motors require a high-power adjustable-frequency inverter.

The only downside of common standard DC motors that I know of is that you have to change the brushes every n years, which I'll gladly take over oil changes. :)

[proee]

Well you forced me into a google search. Here's a good read on dc vs ac type motors used in EVs.

http://www.teslamotors.com/blog4/?p=45

[happenstance]

Thanks for the link.

Though, I still tend to gravitate toward the simplest solutions, and in this case, a series-wound brushed motor is about as simple as it gets.

Regular DC motors have heavy and strong magnets (more expensive), but the series-wound motors are just wires (and, FWICT, a bit less efficient).

Regarding brushless, I'm sure they're quieter and require less maintenance, but they still are more complex than the series-wound DC.

I suppose the AC induction motors have their place, but for the DIY crowd, I think many will stick with the basics.