Direct amplitude control algorithm for microcomputer-based pulsewidth modulation inverter

A novel inverter pulsewidth modulation (PWM) algorithm is proposed in this paper. The desired fundamental amplitude can be controlled directly since the turn-on time in each sampling interval is determined by the “equal subamplitude” theory. The proposed scheme is favored for microprocessor-based implementation because the pulsewidth in each sampling is obtained through the simple computation processes. The harmonic analysis shows that the lower-order harmonics can be eliminated by using this scheme. The theoretical predictions are confirmed by the simulated harmonic spectrum