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Unread 01-03-2006, 09:32 PM
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AKA: Bjorn Westergard
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Re: Inductance of CIMs

Quote:
Originally Posted by Gdeaver
The inductance of a DC motor is one of the parameters that is used when calculating the optimum frequency of the PWM fett H bridge. The power curve can also be plotted. For first robots this is all determined by IFI's victors and Firsts choice of motor. All First teams need to worry about is the joy tick - robot response. There are several posts regarding the curves that can be applied. The manufacture may have this data.
As I understand it, a motor with a large inductance will respond... sluggishly as the magnetic feild builds. In the CIMs the effect is not terribly dramatic.

That said, the inductance needed to be included in this mathematical model, I'm told, because the power curve only provides insight to the motors behavior at a given fixed speed. It does not address how the motor responds as it accelerates.

After some futzing about with a function generator and oscilloscope our alumnus found the result he was after.
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Last edited by phrontist : 01-03-2006 at 09:35 PM.