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Old 09-27-2015, 05:59 PM   #2097 (permalink)
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Ya, the mulss takes a couple cycles off the normal multiply. I think because there are 4 variations:

(signed signed)
(unsigned signed)
(signed unsigned)
(unsigned unsigned)

And if you know what type you are using, the compiler doesn't have to check and maybe saves a little time somehow?

Now for the sensorless,

Ealpha = Valpha - statorResistance*IAlpha - statorInductance*dIAlpha/dt
Ebeta = Vbeta - statorResistance*Ibeta - statorInductance*dIbeta/dt

(Valpha, Vbeta, Ialpha, and Ibeta are all just stuff that you get during the clarke and park transforms and inverse transforms. The steps are identical for ACIM and permanent magnet AC)

EDIT: OK I had made a mistake, and you can't just get the rotor flux angle that way. There's an offset that depends on the speed of the motor. Oh well. It's sort of working now though.
kits and boards

Last edited by MPaulHolmes; 09-28-2015 at 02:43 PM..
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