BCIT Logo

Module 6: Power

Useful Equations

Apparent power: $$ S=VI^* $$

Average (or Active) power: $$ P = Re\{S\} = \|S\|cos(\theta) = V_{rms}I_{rms}cos(\theta) $$

Reactive power: $$ Q = Im\{S\} = \|S\|sin(\theta) = V_{rms}I_{rms}sin(\theta) $$

Total power: $$ S_T= \sqrt{P_T^2+Q_T^2} $$ $$ F_P = \frac{P_T}{S_T} $$