Theoretical Aspects of the Common-Mode Leakage Current Suppression in a Photovoltaic Power Generation System Based on Multi-Level H-Bridge Type Converters

Now days, power generation systems (PGS) based on a solar photovoltaic modules (batteries) and semiconductor converters (PV PGS) are widely used. Recent studies conducted by the international energy agency (IEA) shows that most of the PV PGS used in grid applications. For reducing weight and size factors of PV PGS from its structure eliminate the transformer.Some estimates show that the transformer can occupy up to half the volume and reach half the weight and cost of PV PGS without solar photovoltaic modules. However, the elimination of the transformer leads to common-mode leakage current (CLC) occur, which flows through the parasitic elements of the PV PGS circuit. Common-mode leakage current can be cause of some type's equipment failure. The common-mode leakage current extremely difficult to suppress in some cases with PV PGS designed on H-bridge multilevel converters. The algorithmic capabilities of common-mode leakage current suppression in the PV PGS based on H-bridge type multilevel converters were considered in this paper. Obtained results were verified by simulation.