Reformed hybrid multilevel inverter through photovoltaic for induction motor

Abstract

In recent years, multilevel inverters have gained more attention for high power applications. A multilevel inverter not only achieves high power ratings, but also enables the use of renewable energy sources. Renewable energy sources such as photovoltaic, wind, and fuel cells can be easily interfaced to a multilevel inverter system for a high power application. The proposed method is 15-level multilevel inverter which has number of modules are connected in series. Each module has one switch and one parallel connected diode. Only one switch operates at a time preventing short circuit. This method involves less number of switches associated with more number of voltage levels. The stages with higher DC link have more advantages like low commutation, reduced switching losses, increased efficiency and low input stages with more number of output levels. The input supply is given from the photovoltaic cell. In this paper, a bypass diode technique is introduced to the conventional H-bridge multilevel inverter topology which reduces the number of controlled switches used in the system. It dramatically reduces the switches for high number of levels that reduces the switching losses; cost and low order harmonics and thus effectively improves Total Harmonic Distortion (THD).