RELIABILITY IMPROVEMENT OF PV MODULE THROUGH MODIFIED BYPASS ARRANGEMENT

Abstract

Photovoltaic (PV) generation systems are being developed in response to the rapidly depleting conventional energy sources and the growing demand for alternative energy sources. PV technology is the most widely chosen alternative source among the various options because it is the most abundant. But one of the major problems associated with this technique is the generation of Hotspot in PV panel and this long standing problem is still present even after so much advancement in the technique. However, it does not affect the performance but seriously affect the safety and reliability of the system. In this paper, solution to this problem is proposed which is cost effective and also does not increase the complexity of the circuit. A hotspot mitigation circuit is proposed in which a Mosfet is used, as a switch, which will cut off the entire panel which is under the partial shading condition and the rest of the connection can continue to work smoothly at reduced voltage but at very minute power loss as compared to the prior design. The performance of the modified bypass circuit is demonstrated using a simulation model of a 3×3 Photovoltaic (PV) panel system, and the results are then compared in terms of current-voltage and power-voltage characteristics under various partial shading conditions, with and without modified bypass circuit. . The results are then validate through hardware experimentation on a 3×3 PV panel using EXIDE INDIA LIMITED (EIL-40) modules each have capacity of 40 W.. The results reveal that the proposed modified bypass arrangement effectively reduced the temperature of the affected cell hence the reliability is improved.