Analysis of Leakage Current Elimination in Single Phase Transformerless Inverter for Grid-Tied Photovoltaic Applications Indira , Venmathi Mahendran Research Scholar, Dept of EEE, Associate Professor, Dept of EEE St.Joseph’s College of Engineering, Chennai, Tamilnadu, India

Transformerless Inverter for Grid-Tied Photovoltaic Applications Indira D1, Venmathi Mahendran2 1Research Scholar, Dept of EEE, 2Associate Professor, Dept of EEE St.Joseph’s College of Engineering, Chennai, Tamilnadu, India. 

 Abstract:
In photovoltaic (PV) application, it is possible to remove the transformer from the PV system in order to reduce size, losses, and cost and improve the efficiency. Due to the characteristics of low cost and high efficiency, the transformerless PV gridconnected inverters have been popularized in the application of solar electric generation system in residential market. Unfortunately, presence of the parasitic capacitor between the panel’s metal frame and cells causes the leakage current issue. The leakage current increases current harmonics injected into the utility grid, the radiated, conducted EMI, and losses. Eliminating the leakage current is one of the most important issues for transformerless single-phase photovoltaic (PV) systems. This paper focuses on analysis of leakage current elimination in single-phase transformerless inverter for PV applications. A simple unipolar Sinusoidal Pulse-Width Modulation (SPWM) technique is used to modulate the inverter to minimize the switching loss, output current ripple, and the filter requirements.The main benefits of the proposed inverter are (1) The neutral of the grid is directly connected to the negative terminal of the PV panel, so the leakage current is eliminated, (2) low cost, (3) its compact size, (4) flexible grounding configuration, (5) capability of reactive power flow, and (6) high efficiency. A complete description of the operating principle and analysis of the proposed inverter are presented and simulation results are verified.
Keywords— Charge Pump Circuit, Grid Connected Inverter, Leakage Current Elimination, Photovoltaic, Transformerless Inverter, common mode voltage, parasitic capacitor, sinusoidal pulse width modulation, SPWM.
LINK
http://oaji.net/articles/2017/1992-1537360621.pdf