Low Fourier harmonics PWM pattern synthesis method based on Walsh function

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 to be a linear algebraic equation. Thus the synthesis becomes straightforward. It is the remarkable feature of the proposed method over a conventional method using Fourier series expansion. In addition, the loop synthesis process using Fourier-Walsh transform has been proposed to cut the low-order Fourier harmonics of PWM pattern. Several examples confirm the validity of the proposed synthesis method.