Power Factor Definition

≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡

The phasor diagram is used from the generator’s view. This defines the following

definitions.

Power Factor is defined as a ratio of the real power to apparent power. In a purely

resistive circuit, the voltage and current waveforms are instep resulting in a ratio

or power factor of 1.00 (often referred to as unity). In an in ductive circuit the

current lags behind the voltage waveform resulting in usable power (real power)

and unusable power (reactive power). This results in a positive ratio or lagging

power factor (i.e. 0.85lagging). In a capacitive circuit the current waveform leads

the voltage waveform resulting in usable power (real power) and unusable power

(reactive power). This results in a negative ratio or a leading power factor (i.e.

0.85leading).