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Old 06-04-2010, 02:13 AM   #7 (permalink)
jmedia
ecowannabe
 
Join Date: Feb 2010
Location: San Diego, CA
Posts: 64

Skeeter - '89 Ford Escort LX
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Quote:
Originally Posted by Ryland View Post
with DC motors there are series wound motor with the field coil connected in series with the armature.
Shunt wound motors the field coil is in parallel.
A SepEx motor looks like a Shunt wound motor on paper but has a smaller field coil that gets a lower voltage as the field coil is sepperatly excited (aka Sep-Ex), this allows for better speed control and easy regen braking but apparently (from what I read) not as much brute torque.
A permanent magnet motor does not have a field coil to create the magnetic field, instead it's field magnets are regular magnets, this might sound nice but they tend to produce electrical noise (you will hear the motor running over your radio) and electromagnets can produce a stronger field when needed, the advantage of them is that they work as generators as well so regen braking is easy!
All DC motors need brushes.
Some AC motors have brushes but depending on the AC motor design the job of the brushes can be switched to the solid state electronics of the controller, this means that instead of having a choice of 12 controllers like I have to pick from for my DC electric car, I might have a choice of two, one that is designed for that motor and one that was custom built for that motor and if I had to guess it would cost more then you think your entire project is going to cost, I might be wrong so please keep an open mind and look and research for your self of course!

As far as transmissions go, most people I talk to don't shift there EV much, if ever but instead use the transmission as a simple way to attach the motor to the drive axles without building their own differential.
"wiring up" to an automatic should be simple, but it would be like running with tires that were half flat, your car would feel sluggish, non of that joy you get out of driving an electric car.
Thanks for all the great info, I'll have to research some of that as I don't understand it all (again EV noob)

But I feel like some shifting would be necessary to a bit more efficient because once you hit highway speeds the ev motor would be spinnin like crazy
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