Leakage current suppression for transformerless inverter for grid connected PV power systems

摘要

Due to the driving worldwide environmental demand for the renewable energy resources the photovoltaic power market in the recent years experiences certain amount of the innovations regarding the construction and the operation of the inverter connected to the grid. One such significant development, is that the abolition of the galvanic isolation due to the absence of the transformer which causes safety threats in the event of ground faults. This results in the development of the transformerless CSI inverter which experiences reduced cost, higher efficiency, smaller size and weight. But the use of the CSI injects high earth leakage current into the grid the leakage current generated between the PV panels and the ground. In order to overcome the aforementioned limitations, this paper deals with the effective solution to anticipate the CM ground leakage current using the transformerless Modified Current Source Inverter (MCSI) for grid connected photovoltaic power system. Bssy the use of Maximum Power Point Tracking(MPPT) control technique and SEPIC converter desired output from PV to the inverter is achieved. This advance topology can be modulated using Space Vector Pulse Width Modulation (SVPWM) to produce the reduced output ripple. The experimental results show the performance of the proposed solution in terms of ground leakage current reduction and the experimental studies are analyzed using MATLAB simulation.