The conventional bypass diodes used in solar photo-voltaic panel have side-effects of forward voltage drop, reduction in efficiency and a few operational problems under partial shading condition. In this work, this bypass diode is replaced by an electromagnetic relay through an efficient alternative approach that consumes less power and offers higher efficiency under partial shading condition of solar module. This approach removes the problems like hotspot formation of the solar cell, open circuit fault under shading condition. A part of this work has been reported and published as an Indian patent. In this extended research work, the different components are designed for the partial shading condition. The hardware setup is developed, and hardware results are compared and validated with the simulated results. The proposed electromagnetic method, with no semiconductor device, works efficiently and effectively under partial shading (low irradiance) scenarios.

۱٫ Introduction

In the present era of renewable energy sources, the solar energy has emerged as one of the most eco-friendly source of usable energy. It is extensively used across the globe since solar cells generate different outputs depending on various environmental factors. The solar modules’ performance is reduced to an appreciable extent by the shading effects and hence an urgent need arises for more efficient and reliable solution. Low irradiance and shading conditions are manageable by facilitating the load current through an alternate path and this can be done by using bypass diode. The resistance of the cell under shadow becomes high and this is why the bypass diode requires. The load current determines the amount of power dissipated by the bypass diode. The efficiency of the solar panel is significantly reduced by the bypass diode. That is why it is essential to sensibly arrange the number of bypass diodes in a PV (Photo-Voltaic) module. It is highly significant to reduce the losses in the PV panel having bypass diode.