The development of a generalized multilevel inverter for symmetrical and asymmetrical dc sources with a minimized ON state switch

Abstract

This paper proposes a double source double diode double switch (DSDDDS) multilevel inverter to generate positive voltage and a connecting polarity changing circuit of an H-bridge inverter to generate negative voltage. By connecting the jth number of basic units in series, the desired level is obtained. Various algorithms, such as Natural, Binary, Trinary, and Quasi-Linear sequences, and two proposed algorithms are discussed to determine the magnitude of DC voltage sources in order to generate more stepped levels with fewer switches. The proposed multilevel inverter eliminates the need to turn on additional power switches for different levels, which is the main advantages of this topology. The proposed multilevel inverter is compared to conventional switched diode multilevel inverters in terms of switch count, number of ON state switches per level, driver circuits, and total standing voltage. Real-time results from the OPAL-RT test bench and simulation have validated the proposed inverter.

Keywords

• Multilevel inverter
• DC source selection
• ON state switch
• Pulse width modulation
• Real time simulator (OPAL-RT)