Reduction of leakage current of a CSI based grid connected PV system without Transformer

  V.Diyvarao,  G.Saraswathi

Abstract—The main aim of renewable energy generation is to improve the power quality and to deliver maximum power into the grid with less total harmonic distortion, high efficiency, and small size, low cost. The grid connected PV system with transformer provides isolation and grounding for PV array. But the transformer increases cost and size of the system. Single and two-stage grid connected systems are commonly used topologies in single and three phase PV application. But two-stage technique suffer from higher cost, and larger size, reduced efficiency. Therefore, the single-stage inverter has gained attention. Hence, single-stage single phase grid-connected PV system based on CSI is considered. A double-tuned parallel resonant circuit is considered to eliminate the second and fourth order harmonics on Dc side. A modified carrier based modulation technique provides a continuous path for the DC side current after each active switching cycle. The control structure consists of maximum power point tracking (MPPT) which is implemented by fuzzy controlling technique, a PI controller for AC side current and voltage loop controller. The leakage current due to parasitic capacitance existing in-between ground and PV array is eliminated by using H6 topology technique. Simulation results confirm the dynamic behavior of the proposed system using Matlab/Simulink.

Keywords- Keywords— carrier based pulse width modulation, fuzzy logic, grid-connection, leakage current elimination

Unique Identification Number - IJEDR1703106
Page Number(s) - 735-744
Pubished in - Volume 5 | Issue 3 | August 2017
DOI (Digital Object Identifier) -   
Publisher - IJEDR (ISSN - 2321-9939)

  V.Diyvarao,  G.Saraswathi,   "Reduction of leakage current of a CSI based grid connected PV system without Transformer", International Journal of Engineering Development and Research (IJEDR), ISSN:2321-9939, Volume.5, Issue 3, pp.735-744, August 2017, Available at :http://www.ijedr.org/papers/IJEDR1703106.pdf