Improved H5 circuit based five-level quasi Z - Source inverter with reduced leakage current

Abstract

This paper presents an improved H5 circuit based five-level quasi Z-source inverter for photovoltaic applications. The inverter circuit is formed by utilizing an improvised H5 circuit with a dual quasi Z-source that can produce a five-level stepped voltage waveform rather than a three-level voltage waveform. The developed modulation technique results in a trapezoidal common mode voltage. An active filter was used to eliminate the leakage current and filter out the harmonics in order to feed the grid voltage. The converter also possesses the reactive power sourcing capability, which helps in supporting changing load conditions. The leakage current resulting from this converter is well within the stipulated IEEE standards.