An enhanced H-bridge multilevel inverter with reduced THD, conduction, and switching losses using sinusoidal tracking algorithm

Abstract

In this paper, an enhanced H-Bridge multilevel inverter is proposed with the sinusoidal tracking algorithm. The proposed multilevel inverter (MLI) consists of two half H-Bridges cascaded with two unidirectional switches, n direct current (DC) sources, and (n-2) number of bi-directional switches together to form an enhanced H-Bridge (EHB) multilevel inverter. The output voltage levels of an EHB MLI depends on the number of DC sources, the number of bi-directional switches, and the relationship between the magnitude of left-side and right-side DC sources. With the addition of DC sources, bidirectional switches, and employing the sinusoidal tracking algorithm, the performance of the inverter is enhanced with features like an increased number of levels and a reduction in the total harmonic distortion and switching losses. In all the modes of operation of the proposed inverter, only three switches are "ON", so that conduction losses are less. The proposed enhanced H-Bridge MLI is simulated using MATLAB/Simulink R2017a, and is verified with the experimental result.