Elimination of Leakage Current in Grid-Tied PV Applications

New topology for transformerless inverter, connected to grid with PV system as a source is introduced in this paper. It incorporates charge pump circuit included inverter. This concept is used specially, to supply high side power circuitry. It produces negative output voltage at the output terminals of the inverter. Therefore when the neutral of grid and negative terminal of inverter are connected, the problem of leakage current and common mode voltage is totally ejected. This whole circuitry includes two schottky diodes, two capacitors and four MOSFETs with LCL filter. The switching pattern necessary to trigger the power switches is generated with modified SPWM technique. The control strategy using modified single phase p-q theory is introduced to control the injected current into grid by regulating the power. Finally this gives sinusoidal output current. A simulink model of this proposed work is given, which consists of open loop and closed loop models. The simulation results verify the performance as per requirements of topology.