Sine Averaging and Duty Ratio Approach PWM Techniques at Low Switching Frequencies

Abstract

The concept of a Sine PWM inverter is based on the assumption that a sine wave can be assumed to be constant for one switching cycle. This assumption holds true for low voltage high switching frequency needs, but as power or voltage requirements increase, having a high switching frequency can result in high switching losses, necessitating the use of a PWM inverting technique that can efficiently work with low switching frequencies. This paper examines several possible versions of sine PWM algorithms for low-frequency applications, focusing on their fundamental frequency content and total harmonic distortion. A comparison is made for inverters (utilising Pure sine wave as a reference and stepped sine wave as a reference) with existing and proposed method taking the cases of scaled and non-scaled. With the thorough analysis of all the cases, A stepped sine methodology Sine Averaging and Duty Ratio Approach that offers comparatively better results than existing techniques has been proposed.