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Old 01-16-2008, 07:59 PM   #2 (permalink)
AndrewJ
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Quote:
Originally Posted by WaxyChicken View Post
Also, while i'm at it, some of the EV Cars I've seen on the news use more than one motor located at the wheels to reduce mechanical energy loss. How do they ensure that both motors turn at the same rate?
Physics and electronics help.
The car is going to keep trying to go in a straight line, thereby dictating that both hub motors will have to keep spinning at the same RPM. If one motor were to try to spin slower or faster the car would begin to deviate from it's trajectory, something it does not want to do.

Electronics may help with the acceleration side, controllers can keep track of a motors RPM, and would ensure that they are perfectly matched unless of course you're accelerating around a curve, in which case the motors won't be matched, mimicking the action of a differential in a traditional car.
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