Sidharth Sabyasachi

A Three-Phase Hybrid Cascaded Modular Multilevel Inverter for Renewable Energy Environment

This paper presents a three-phase hybrid cascaded modular multilevel inverter topology which is derived from the proposed modified H-bridge module. This topology results in the reduction of number of power switches, losses, installation area, voltage stress and converter cost. For renewable energy environment such as photovoltaic (PV) connected to the microgrid system, it enables the tranformerless operation and enhances the power quality. This multilevel inverter is an effective and efficient power electronic interface strategy for renewable energy systems. The basic operation of single module and the proposed cascaded hybrid topology is explained. The ability to operate in both symmetrical and asymmetrical modes is analyzed. The comparative analysis is done with classical cascaded H-bridge and flying capacitor multilevel inverters. The nearest level control method is employed to generate the gating signals for the power semiconductor switches. To verify the applicability and performance of the proposed structure in PV renewable energy environment, simulation results are carried out by MATLAB/Simulink under both steady-state and dynamic conditions. Experimental results are presented to validate the simulation results.

An asymmetrical multilevel inverter topology with reduced source count

In this paper, an asymmetrical topology for cascaded multilevel inverter based on basic converter unit, series unit and full-bridge is proposed. It offers lower total harmonic distortion, switching losses and voltage stress on switches than conventional inverters. An algorithm to determine dc voltage sources magnitudes is proposed. The gating signals for the power switches are generated by employing Nearest Level Control (NLC) method. This structure allows a reduction of the system cost and size. Effectiveness of the proposed topology has been demonstrated by analysis and simulation.

Cascaded Multi-level Inverter Topology Developed from a Modified H-bridge

Abstract In this paper, a single-phase cascaded multi-level inverter topology is proposed. It is basically developed from a modified H-bridge module. This topology reduces the switch count, the gate drive requirement, and voltage stress. The significant advantages of the proposed inverter are modular structure, simpler control, and lower number of switches. The Nearest Level Control algorithm is employed to generate the gating signals for the power switches. To verify the performance of the proposed structure, simulation results are carried out by MATLAB (The MathWorks, Natick, Massachusetts, USA)/SIMULINK. Experimental results are presented to validate the simulation results.