A New Multilevel Converter for PV Power Generation Systems with Leakage Current Suppression

Abstract: This paper studies major reasons causing the common-mode leakage current flow in a photovoltaic (PV) power generation system. It is noted that the main reason for the formation of a common-mode leakage current is the presence of harmonic common-mode voltage at the output terminals generation system. To suppress the common mode leakage current usage of a new topology of a single-phase multilevel power converter and specified space vector PWM strategy are suggested. This solution has made it possible to keep the common-mode voltage constant and reduce the leakage current to zero. A simulation model is given to prove the effectiveness of the presented multilevel topology and its PWM strategy.

Keywords: multilevel voltage source converters, common–mode voltage, common–mode leakage current, photovoltaic power generation system, space vector pulse width modulation