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Old 10-14-2014, 06:26 PM   #1205 (permalink)
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Originally Posted by MPaulHolmes View Post
Yes! Well, what I have been doing is, when there is a gross violation of the clamping (VdClamped - Vd) > 100, knock down the commanded Id by 100. As if giving it another chance, allow the "commanded" current crawl back very slowly to the ACTUAL commanded current. If there's another violation of Vd or Vq, tar whoop them again!

The process needs to be cleaned up, but that has worked best. Another way is, I think I need to find the relationship between Id, Iq and RPM and load for all possible values (for a given AC voltage). Because that wouls be difficult, I'm trying to be content with only using Vd, Vq, Id, and Iq, since I have those.
If you had all possible values Id, Iq and RPM would it be able to be represented by a best fit formula?

What if the knockdown value was simply linked to the RPM.
knockdown = RPM / 100
So that at higher RPMs the knockdown was more aggressive.
Actually this might result in negative values for the commanded Id.
Maybe work out the percentage the current RPM is of the motors maximum RPM.
Then knock down the commanded Id by the same percentage.
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