Message text written by Randall Young
>Even crazier, a DC motor actually does act like a generator at the same
time
it's being a motor. The reason the current it draws goes down as it's
speed
goes up is a phenomenon called "back EMF", where the voltage generated by
the motor partially counteracts the voltage applied. If the motor is
turned
fast enough, the back EMF exceeds the applied voltage, and the motor starts
to generate power. (For a parallel wound, or permanent magnet motor.
Series-wound is a different story, because the current through the armature
is also the field current.)
<
This is a little more in depth than I wanted to get but indeed. This is
why locked rotor current is more than full load current at rated speed.
This motor/generator effect is used in wheel chairs and electric vehicles
and other electric motor drives where speed variation is desired. If the
circuit is complex enough you can take that energy generated and put it
back into the battery to extend range. This is called regenerative
braking. But none of this applies to LBC's. Yet.
Dave
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