What is the formula for the calculation of Power factor?

Answer 1

In an ac circuit, the power P consumed can be expressed in terms of applied voltage, V, current I, resistance R and the phase angle A between current and voltage. V, I are instantaneous values.

P = V.I. cos A = I*2.R .
From a phasor diagram, we get Cos A = R/Z
At resonance, when Inductive reactance XL = capacuitative reactance Xc; the total impedance is minimum, Zmin = R;
Cos A = 1 and the Power consumed is maximum, Pmax = VI.

Hence, in general, P = V.I. cos A = Pmax. Cos A.
So, the actual power consumed, in general, is less than the maximum power that can be consunmed (at resonance) by a factor, Cos A. Hence, Cos A is called the power factor.

One may define power factor = P/Pmax
One may also defione powerfactor as Cos A =R/Z

Answer 2

Power Factor Formula

Answer 3

Power Factor Equation

Answer 4

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What is the formula for the calculation of Power factor?

Answer 5

Power Factor
For a DC circuit the power is P=VI, and this relationship also holds for the instantaneous power in an AC circuit. However, the average power in an AC circuit expressed in terms of the rms voltage and current is
P[average]=VI x cos[phy]
where [phy] is the phase angle between the voltage and current. The additional term [cos phy] is called the power factor


From the phasor diagram for AC impedance, it can be seen that the power factor is R/Z. For a purely resistive AC circuit, R=Z and the power factor = 1. R=Resistance, Z=Impedance

Cos [ phy] = R/Z = Power Factor

Answer 6

It is dangerous to practice engineering by relying on formulas. It's far better to understand and work through the fundamental physical principles. If you have a 100kW load at 0.8 power factor, that means that the 'apparent' power, S, is 100/(0.8) or 125kVA. And the reactive component of would be 125kVA X sin (arc cos 0.8) or 75kVAR. That is, the total load is 125kVA = 100kW + j75kVAR. Therefore, if you add 75kVAR of capacitors, the net load will be 100kW at unity power factor.

Answer 7

P=VI
Power=Voltage X Current

Answer 8

For calculating average power in an a.c. circuit over the half cycle, we use power factor. It is equal of cos (phi), where phi is the phase difference between the instantneous current and voltage in the a.c. circuit. Using impedence triangle we can find out the value of power factor.

Power factor, cos (phi) = resistance (R) / impedence (Z)

for pure resistive a.c. circuit, Z = R, cos (phi) = 1

for pure capacitive or inductive circuit, R = 0, cos (phi) = 0

Answer 9

while you calculate impedence, you will have values of inductive and capacitive reactance. take their difference, square it and add with the square of resistance. take its square root. say it is "z". now take the ratio of resistance and "z" , you have obtained the power factor. you can try out some other method too. when you represent all the quantities by phasor diagram then the take the cosine of "fi" you will get power factor.

Answer 10

the formula for calulating the power factor is:-
cos$=v/i
where $ is angle b/w voltage and current.