A single-chip microprocessor-based PWM technique for sinusoidal inverters

A sinusoidal pulsewidth-modulation (PWM) technique suitable for single-chip-microprocessor-based control is described. The scheme can be considered as a digital alternative to the analog subharmonic method (SHM) in the sense that online real-time PWM control is possible, synchronization between carrier wave and signal wave is unnecessary, and low-order harmonics in the output voltage are well suppressed. The maximum output voltage is 15% larger than that obtained by the subharmonic modulation method at the same carrier frequency.<<ETX>>