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Old 09-15-2015, 04:36 PM   #2006 (permalink)
MPaulHolmes
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Is there an issue with only 60 samples, or perhaps that MAY not be enough samples?

Ya, I think you are right. 60 samples looks awful good on a graph. Even 20 samples for a cycle is a pretty good approximation to the sine wave, and that would be 30,000RPM. I think I spoke too soon before about needing to increase the frequency.

It's possible that bad rotor time constants were creating a terrible model of the motor, and it was totally messing up the spinning. I'm very interested in seeing how it works with the
1<cr>
2<cr>

It should give very fine control and since we will be using a rotor time constant that is accurate for the motor, and good PI values, it should be good to go. I'll be interested in seeing if any problems arise. IT's not a problem to slow the ramp rate down so it's not so crazy. Maybe because your motor is so powerful, I need to do a slower ramp rate than what I'm using. It's sort of hard to explain, but I'm doing IdRef, IqRef, and also IdREfRef and IqRefRef. IdRef and IqRef get clamped whenever the PI loop is overshooting a voltage disk, then they try to ramp back up to the RefRefs.. but I should make sure the ramp back isn't too aggressive.
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