A new transistor clamped 5-level H-bridge multilevel inverter with voltage boosting capacity

Abstract

Multilevel converters offer high power capability, resulting with lower output harmonics and lower commutation losses. Their main disadvantage is their complexity, requiring a great number of power devices and passive components, and a rather complex control circuitry. This paper presents a new topology of the multilevel inverter with feature like output voltage boosting capability along with capacitor voltage balancing. The proposed multilevel inverter uses transistor clamped H-bridge (TCHB) with an bidirectional switch and four auxillary switches producing a boost output voltage. The single unit of new topology produces five-level output with output voltage double the input DC voltage where as a single unit of conventional H-bridge produces three-level output voltage similar to input DC voltage. The comparison has made between the proposed five-level inverter and conventional cascaded five-level inverter in terms of the output voltage, total harmonic distortion (THD), No. of switching devices used etc. The analysis of the output voltage harmonics is carried out and compared with conventional cascaded H-bridge inverter topology. The proposed multilevel inverter topology is modeled using matlab / simulink. From the results the proposed inverter provides more output voltage.