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Unread 05-01-2011, 01:28
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Ether Ether is offline
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Re: Modeling motor control



Look at the difference in current waveforms for a CIM with locked rotor driven at 5% duty with a Jag vs a Victor.

This is a simulation using R=0.090 ohm & L = 200uH.


At 15KHz, the current varies from ~7.4amps to 7.7amps. The RMS is 7.6amps and the algebraic average is 7.6amps.

At 150Hz, the current varies from ~1.8amps to 18.7amps. The RMS is 8.4amps and the algebraic average is 6.7amps.

Since average motor torque is created by algebraic average current, and motor heating is created by RMS current, the 150Hz waveform produces less average torque and more motor heating.



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Last edited by Ether : 05-01-2011 at 02:09.