An Efficient Grid Connected Photovoltaic System Based on H6 Transformer-less Inverter

Abstract

Grid-connected photovoltaic (PV) systems based on transformer-less inverters have been widely used. Various topologies of transformer-less inverters are presented. The requirements of minimizing leakage current through transformer-less inverters and maximizing the power generated from PV arrays are of great importance. This paper presents a complete system that can effectively minimize the leakage current to safe values. In addition, operation at maximum PV array power point is realized. The system is based on modified H6 transformer-less inverter to minimize the leakage current. Perturbation and Observation P&O maximum power point tracker in addition to a dc-dc boost converter are utilized to achieve the second target. Analysis of each part and system controllers in the proposed system are presented in detail. Losses and system efficiency are introduced. Effects of sun irradiance variations are included. Simulation results prove the effectiveness of the proposed system.