electric motor controller

[Clipped]

can someone help explain how an electric motor controller operates for an electric cars motor?

something like an amplifier, or basicly a PWM power supply? is it class D, G...etc?

thanx

[jol50]

Here is a little info, I think they are more or less one tiny amp output stage with a variable controller using mosfets. When I had my car I could hear it whine from the switching.
http://www.math.niu.edu/~behr/RC/speed-ctl.html

[Simpleton]

On small engines, like rc cars, the motor is controlled by switching FETs via PWM. I assume the control principle is the same for large DC motors.

[Clipped]

reason im asking is im getting into electric cars (full size). so i can get off gas man, this $hits killing my wallet.

but these controllers need to handle around 96-140 volts and 1000 amps! ... and thats for the small guys. Ive wound a few generators, but motors need timing, unless theyre slip ring designs...even then without a controller, its full torque from the beginning and that aint good.

maybe i can talk Perry into designing one...

[jol50]

Thought you meant RC car, but I imagine they work the same.

Only ones I know of are the performance controllers for golf carts, but most are 48v. You might look up the manufacturers and find something you need? Certainly the expensive part of electric power.

[Perry Babin]

There are motor controllers available. The one on the following site is good for 400 amps continuous.

http://www.ecycle.com/buckboost.html

[jol50]

Originally posted by Perry Babin
There are motor controllers available. The one on the following site is good for 400 amps continuous.

http://www.ecycle.com/buckboost.html

Interesting company

[Clipped]

that one looks similiar to the 'zilla' controller, wonder if theres any affiliation...

[ppia600]

There are mosfets that have well over 100 amp current ratings... you could parallel enough to have over 1000 amp capability. Making it quiet enough to deal with would be the trick. Imagine an r/c car's switching noise multiplied by 100 lol.