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Unread 19-05-2014, 15:07
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Ether Ether is offline
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motor Ke and Kt Quiz


Here are the specs for a hypothetical ideal brushed motor, whose performance is strictly linear between the free and stall points:


The specs at 12 volts are:

FreeSpeed = 400 radians/sec

FreeCurrent = 0 A

StallTorque = 0.4 Nm

StallCurrent = 20 A


Calculate Ke:

Ke = 12/400 = 0.03


Calculate Kt:

Kt = 0.4/20 = 0.02


Question:

Why are Ke and Kt not equal?