Improvement of pulse width modulation techniques

Pulse width modulation (P.W.M.) techniques, adopted in inverters for modern variable speed drives, allow an easy adjustment of the fundamental component of the output voltage. Their use, however, entails certain disadvantages such as the complexity of the electronic control circuits and especially the deterioration of the performance of the inversion circuit. There such disadvantages can be reduced by resorting to improved modulation techniques. This paper deals with an advantageous modification of the shape of the modulating wave in the suboscillation P.W.M. technique