A Sinusoidal PAM-PWM Inverter

Abstract

A new strategy, using both PAM (pulse amplitude modulation) and PWM (pulse width modulation) in combination, for a power inverter is described. The output waveform in the proposed PAM-PWM inverter are investigated both theoretically and experimentally. The line-to-line voltage waveform includes the fundamental component and the sidebands of the carrier frequency. Lowerorder harmonics are not included in the output waveform. The amplitude of the fundamental component increases 15% more than that of a conventional sine-wave inverter. Since each inverter arm does not operate during two-thirds of the period, the heat generated in the devices is reduced, i.e., the size of the inverter system can be minimized because of the reduction in the heat dissipating equipment.