Photovoltaic Grid-connected Power System with Common Mode Leakage Current Elimination using an Improvised Transformer less Inverter

Authors(2) :-Mohammed Safique, Dr. Harikumar Naidu

To remove the common-mode leakage current in the transformer less photovoltaic grid-connected system, an improved single-phase inverter topology is presented. The improved transformer less inverter can use the same low input voltage as the full-bridge inverter and guarantee to completely meet the condition of eliminating common-mode leakage current. Both the unipolar sinusoidal pulse width modulation (SPWM) along with the double frequency SPWM control strategy can be used to implement the three-level output in the presented scheme. The high efficiency and convenient thermal design are achieved due to the decoupling of two extra switches connected to the dc side. Moreover, the higher frequency and lower current ripples are achieved by using the double-frequency SPWM, and thus the total harmonic distortion of the grid-connected current are minimised. Furthermore, the effect of the phase shift between the output voltage and current, and the influence of the junction capacitances of the power switches are studied in detail. Simulation for unipolar and bipolar SPWM are being carried out to validate the result.

Authors and Affiliations

Mohammed Safique
Department of Electrical Engineering, Anjuman College of Engineering and Technology, Sadar, Nagpur, Maharashtra, India
Dr. Harikumar Naidu
Department of Electrical Engineering, T.G.P. College of Engineering & Technology, Nagpur Maharashtra, India

Common-Mode Leakage Current, Junction Capacitance, Phase Shift, Photovoltaic (PV) System, Sinusoidal Pulse Width Modulation (SPWM) Strategy, Transformer Less Inverter.

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Publication Details

Published in : Volume 2 | Issue 6 | November-December 2016
Date of Publication : 2016-12-30
License:  This work is licensed under a Creative Commons Attribution 4.0 International License.
Page(s) : 332-339
Manuscript Number : IJSRST162671
Publisher : Technoscience Academy

Print ISSN : 2395-6011, Online ISSN : 2395-602X

Cite This Article :

Mohammed Safique, Dr. Harikumar Naidu, " Photovoltaic Grid-connected Power System with Common Mode Leakage Current Elimination using an Improvised Transformer less Inverter", International Journal of Scientific Research in Science and Technology(IJSRST), Print ISSN : 2395-6011, Online ISSN : 2395-602X, Volume 2, Issue 6 , pp.332-339, November-December-2016.
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