The SPWM waveform has harmonics of several orders in the phase voltage waveform , the dominant
ones are the fundamental and other of order of n and n±2 where n=fc/fm. With the method of
Selective Harmonic Elimination, only selected harmonics are eliminated with the smallest number of
switching. For a single phase-SPWM waveform with odd and half wave symmetry and n chops per
cycle as shown in fig.