Introduction

Description

The purely sinusoidal voltage

in the time domain can be represented by a complex rms phasor

For these quasi stationary phasor the following relationship applies:

This equation is also illustrated in Fig. 1.

Fig. 1: Relationship between voltage phasor and time domain voltage

From the above equation it is obvious that for t = 0 the time domain voltage is v = cos(φ_v). The complex representation of the phasor corresponds with this instance, too, since the phasor is leading the real axis by the angle φ_v.

The explanation given for sinusoidal voltages can certainly also be applied to sinusoidal currents.

See also

AC circuit, Power, Reference system