Advanced topology to minimize leakage current grid-tied PV systems

Recently the use of photovoltaic system is increased due lots of availability and pollution free energy generation. Then the use of solar inverters is widely increased. Today, transformer-less inverters are becoming more popular for grid tied photovoltaic system because of its high efficiency and low cost. One of the disadvantages faced by the system is due to fluctuating common mode voltage, the leakage current will flow through the whole grid tied PV system which violates the safety regulations. Also the reactive power flow in the whole unit cannot be regulated. So all these issues can be minimized by improving the existing topology of grid tied transformer-less inverter. The main aim of this paper is the analysis, design and verification of improved transformer-less topology and control strategies to minimize leakage current and reactive power flow of PV inverter topologies in order to achieve the standard requirements and make them safe for human interactions. Simulations were done using MATLAB/ SIMULINK. High conversion efficiency and improved power factor are achieved.