Optimal PWM waveform modelling for on-line AC drive control

The authors demonstrate that an optimal pulse width modulation strategy may be accurately implemented online for AC motor drive applications. The strategy has the distinct advantage of almost total elimination of selected bands of harmonics with control of the fundamental. The initial roots of the equations describing the harmonic amplitudes are determined by reliable expressions. By resorting to accurate modelling techniques, it is possible to define an analytical expression describing the law governing the switching angles. The expression is simpler to implement that those used in sampling strategies as it does not involve transcendental terms but uses pure algebra, and requires no elaborate stored functions.