Switched-capacitor based multilevel inverter for renewable energy system

Abstract

In recent years, the design of multilevel inverter topologies has become an important research field for researchers to further enhance the effectiveness of inverter systems due to the increased availability of renewable energy sources, for instance, pv systems. the multilevel inverter has an important feature that can improve output waveform quality. the main idea is to utilize a simple circuit technique called switched-capacitor with pulse width modulation pwm control technique so that multilevel voltage can be realized across a capacitor. the switched-capacitor design cell is connected in a series-parallel configuration to obtain voltage multiplication and charge the capacitor. simultaneously, it can boost the output voltage two times without a dc-dc converter with the least number of components used, thus decreasing complexity for the design and reducing the costs. the proposed inverter (with integrated switched-capacitor multilevel inverter technique) can generate a linefrequency with five levels near sinusoidal ac output voltage using only six switches, using one dc voltage source only. the simulation is performed in matlab/simulink. the results show that the proposed multilevel inverter works correctly to produce a minimum number of switches and five-level waveforms for the multilevel output waveform.