3 Phase AC Induction Motor Question

Is it actually true that the 3-Phase AC induction motor can reverse as a generator!?! Don't you need an axial winding with excitation or permanent magnets around the core?!




Over to Dan Bentler:
#1: YUP.

#2: NOPE.
All motors can be generator and all generators can be motors. Paralleled alternators have reverse power controls to prevent them from becoming motors to prevent damage to prime mover.

One of the things you DO NOT do when switching from hi to low speed on motors is to do it quickly.

You should let motor stop and restart. The reason is especially on AC motors is that the motor is generating and can be out of phase - you will see the motor and load jerk when you get it wrong. Also doing this quickly the motor instantaneously goes from 3600 to 1800 RPM.
- Dan

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This is great - tell me more
by: Chris Jefferies

I have little electronic experience, but was thinking in terms of EV's that having a variable speed motor direct driving each wheel, would be a more efficient way of powering a vehicle. My main assumption for this is that using a single motor through a transmission system causes a lot of lost energy through components.
My assumption has also been that there is very little difference between an generator (alternator) and an electric motor, therefore when a wheel is not being driven by the motor, that essentialy the motor could be used as a generator to replace energy used from the battery, as the wheel is still in motion, therefore the electromagnetic field created by this action could be harnessed. My thoughts are that the motion would be computer monitored and regulated.
Is this feasible to help maintain a car at 100kph over say a 5-8 hour period

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