A Novel Pulse Width Amplitude Modulation for Elimination of Multiple Harmonics in Asymmetrical Multilevel Inverter

Abstract

For medium voltage high power applications the low switching frequency PWM techniques for power converters is preferred. In preprogrammed low switching frequency based PWM technique, the main difficulty is in solving the set of non linear transcendental equations for obtaining switching instants. Also, the number of harmonics eliminated from the output are dependent on the number of switching angles. Moreover, there is no control on the non eliminated harmonic components. In this paper a new pulse width amplitude modulation technique have been proposed to eliminate multiple harmonics from the output voltage waveform. The mathematical modelling is first developed and consequently switching instants have been computed. An FPGA based hardware realization of multilevel inverter is given to validate the proposed concept.