Analysis of Transformer less Inverter For Grid-Connected Photovoltaic Power System Design

Authors(2) :-Lakshmi Narayana. N, Dr. Dalvinder Kaur Mangal

The traditional grid-connected PV inverter includes either a line frequency or a high frequency transformer between the inverter and grid. The transformer provides galvanic isolation between the grid and the PV panels. In order to increase the efficiency, to reduce the size and cost, the effective solution is to remove the isolation transformer. It leads to appearance of common mode (CM) ground leakage current due to parasitic capacitance between the PV panels and the ground. The common mode current reduces the efficiency of power conversion stage, affects the quality of grid current, deteriorate the electric magnetic compatibility and give rise to the safety threats. In order to eliminate the common mode leakage current in transformerless PV system, the concept of virtual DC bus is proposed in this project. By connecting the grid neutral line directly to the negative pole of the DC bus, the stray capacitance between the PV panels and the ground is bypassed. The CM ground leakage current can be suppressed completely. Virtual DC bus is created to provide the negative voltage level for the negative AC grid current generation. The virtual DC bus is realized with the switched capacitor technology that uses less number of elements. Therefore, the power electronic cost can be reduced. This topology can be modulated with the unipolar SPWM to reduce the output current ripple. A smaller filter inductor can be used to reduce the size and magnetic losses. The simulation result of the proposed topology using MATLAB/SIMULINK is presented.

Authors and Affiliations

Lakshmi Narayana. N
Research Scholar, EEE Department SUNRISE University, Alwar, Rajastan, India
Dr. Dalvinder Kaur Mangal
Professor Department of Electrical Engineering, SUNRISE University, Alwar, Rajastan, India

Common Mode Leakage Current, Transformerless Inverter, Unipolar SPWM.

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Publication Details

Published in : Volume 1 | Issue 2 | September-October 2016
Date of Publication : 2016-10-30
License:  This work is licensed under a Creative Commons Attribution 4.0 International License.
Page(s) : 184-189
Manuscript Number : CSEIT1833182
Publisher : Technoscience Academy

ISSN : 2456-3307

Cite This Article :

Lakshmi Narayana. N, Dr. Dalvinder Kaur Mangal, "Analysis of Transformer less Inverter For Grid-Connected Photovoltaic Power System Design", International Journal of Scientific Research in Computer Science, Engineering and Information Technology (IJSRCSEIT), ISSN : 2456-3307, Volume 1, Issue 2, pp.184-189, September-October-2016.
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