how can we derive power factor equation p=vi cos phi?
derivation?
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Answer / kiran antony
AC power flow has the three components: real power(Active power)(P), measured in watts (W); apparent power (S), measured in volt-amperes (VA); and reactive power (Q), measured in reactive volt-amperes (var)[3].
The power factor is defined as:
.
In the case of a perfectly sinusoidal waveform, P, Q and S can be expressed as vectors that form a vector triangle such that:
If is the phase angle between the current and voltage, then the power factor is equal to the cosine of the angle, , and:
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