# NCEES # 131



## electric (Oct 26, 2010)

Can someone please explain, the relationship KVAR directly proportional to voltage square?

The charge of the capacitor is Q = 1/2(CV^2). How that relates to KVAR?


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## knight1fox3 (Oct 26, 2010)

Well perhaps a few definitions may help you.

The power triangle equation is S2 = P2 + Q2

real power (P) is defined as I2*R = V2/R

reactive power (Q) is defined as I2*X = V2/X

Does that help?


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## BamaBino (Mar 30, 2011)

knight1fox3 said:


> Well perhaps a few definitions may help you.
> The power triangle equation is S2 = P2 + Q2
> 
> real power (P) is defined as I2*R = V2/R
> ...


I'm organizing my notes and worked problems according to the NCEES Power Exam Specifications outline.

Would you put this problem under:

II.A.4 Phasor diagrams or

IV.A.3 Power factor correction and voltage support?

Thanks


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## Dolphin P.E. (Mar 30, 2011)

BamaBino said:


> knight1fox3 said:
> 
> 
> > Well perhaps a few definitions may help you.
> ...


It is more likely a "Capacitor Derating".


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