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Default Motor/Generator Analysis

I have measured the DC resistance of a split-phase capacitor run
induction motor's two windings. They are 53 and 35 ohms. The motor is
impedance protected. Using the nameplate voltage and current, I have
calculated the total impedance at 60 Hz to be 110 ohms. This total
impedance is larger than the DC resistance, and so I have algebraically
subtracted the resistance from the total impedance to get the inductive
impedance, but I don't know if I did that step right:

http://users.aol.com/DGoncz/Publicat...orAnalysis.bmp

I am pretty sure about R1/R2 = X1/X2 although the winding *are*
different colors and could be different gages, but I am not sure about

1/(1/(R1+X1) + 1/(R2+X2)) = 110 ohms

I don't know if you can add a resistance and an inductive impedance
arithmetically this way. I have seen things like

R1 at angle 0 degrees + X1 at angle 90 degrees =
sqrt(R1^2 + X1^2)

I have invested hundreds of dollars into this motor/generator and while
I would like to avoid a rewind, these high resistances make a rewind
look inevitable. If I can get a good model, though, I may find a Q1
for some capacitance, and that would indicate, I think, that
self-excitation could commence.

What is not shown in MotorAnalyis.bmp is R1 in series with L1 and so
X1, and R2 in series with L2 and so X2, and R1/L1/X1 in parallel with
R2/L2/X2 and the capacitor C.

Yours,

Doug Goncz
Replikon Research
Falls Church, VA 22044-0394

 
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