Synthesis Method of PWM Pattern Based on Walsh Function

Abstract

This paper proposes the simplification of the synthesis method of PWM pattern by using the Walsh function. The digital nature of the Walsh function makes the relation between the Walsh spectrum and PWM pattern being a linear algebraic equation. Thus the synthesis becomes straightforward. It is the remarkable feature of the proposed method over a conventional method using Fourier expansion.
In addition, by using Fourier-Walsh transform, an iterative synthesis process can reduce low-order harmonics of the PWM pattern in Fourier spectrum. Several examples confirm the validity of the proposed synthesis method.