Pure Sinusoidal Output Single-Phase Current-Source Inverter with Minimized Switching Losses and Reduced Output Filter Size

Eka Rakhman Priandana,Toshihiko Noguchi

doi:10.3390/electronics8121556

Abstract

This paper proposes a novel single-phase current-source inverter that generates a pure sinusoidal waveform with minimized switching losses and using a small-size output filter capacitor. The proposed method is investigated by incorporating a conventional multilevel current-source inverter with a linear amplifier. The conventional multilevel technique uses fundamental switching frequency instead of using high-switching frequency modulation for the H-bridge circuit. The linear amplifier such as class-A or class-D types has a function to reform the staircase waveform generated by the multilevel inverter into a pure sinusoidal by using superimposition technique. As a result, pure sinusoidal output current is generated with a small ripple and the system only requires a small output filter capacitor for smoothing the waveform. Based on the simulation and experimental results, the proposed system presents not only the optimal configuration, but also an option as to whether to obtain excellent power efficiency or very low output harmonic. Implications of the results and future research directions are also presented.

Highlights

Direct current (DC) to alternating current (AC) converters, or inverters, are basically operated by means of a switching action to optimize their power conversion efficiency
In order to verify the proper operation of the proposed hybrid multilevel CSI (MCSI) and investigate the Results correlation between efficiency-total harmonic distortion (THD) with switching frequencies, output filter capacitor sizes, and the
With switching frequencies, output filter capacitor sizes, and theThis number simulation intended to show the operation principle is consistent with the proposed concept

Summary

Introduction

Direct current (DC) to alternating current (AC) converters, or inverters, are basically operated by means of a switching action to optimize their power conversion efficiency. In order to minimize the output noise or harmonics caused by switching modulation, a passive L-C filter is indispensable [1]. Linear power amplifiers such as class-A, class-AB, or class-D can generate a pure sinusoidal waveform with very low noise. Poor power conversion efficiency is their main issue, so that they are not suitable for power inverters [2,3,4]. The primary goal when constructing a power inverter is generating pure sinusoidal waveform with very low output harmonics without forfeiting the power efficiency [1]. Researchers and engineers have adopted several approaches to reach the requirement by either using high-switching frequency modulation, enlarging the output

Methods

Results

Conclusion