Single-phase power system
6 03 2009The power in a single-phase system is shown in figure. In the figure current (I) lags voltage (V ) by an angle ?. The current has two components – the energy component and the watt less component. Only the energy component has a power value. Hence, the power in a single-phase circuit is given by the following equation:
V×I×cos?
Where
P = power (watts)
V = voltage (rms)
I = current (rms)
cos? = power factor.
