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Old 10-11-2010, 07:23 PM   #16 (permalink)
UFO
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Quote:
Originally Posted by rgathright View Post
Actually, the savings with electric motors comes in when you are cruising because they can just "sip" on the batteries to keep the car at speed.

Electric motors consume massive amounts of power when taking off because stall rotor current creates a "short" of sorts against the batteries. For this reason, gasoline engines are preferred for getting the car up to speed.
Take a look at the posted graphs. The AC motor in the Prius, like most electric motor applications, actually do not "consume massive amounts of power", they actually peak torque at zero RPM. Peak power occurs with RPM. You may be mistaking power for current, and any AC controller worth its silicon is going to control that zero RPM current.

The very reason that locomotives use electric motors (aka series "hybrid") is that peak torque at zero rpm enables the train to move from a stop. Just try to make a mechanical drive that can deliver that kind of torque...
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