Power Factor

Power Factor (pf)

Ratio of real power (P) to apparent power (|S|), representing the efficiency of power transmission.

pf = \frac{P}{| S |} = \cos ϕ

Where,

Properties

Power Factor	Power Angle	Phase Relation	Load
Unity	$ϕ = 0$	$V$ and $I$ are in phase	Purely Resistive
Lagging	$ϕ > 0$	$I$ lags $V$	Inductive
Leading	$ϕ < 0$	$I$ leads $V$	Capacitive
Zero	$ϕ = \pm 90^{\circ}$	$V$ and $I$ are orthogonal	Purely Reactive