Design and Implementation of Off-Grid Solar Inverter for Residential Application

Abstract

Renewable energy sources have been identified as a potential solution to shortage in power generation especially in the developing countries of the world. The desire for alternative and clean energy has induced a rapid growth in the number of solar power buildings across the globe. Photovoltaic module generates direct current which cannot be used directly by many home appliances, so there is need for an inverter. This study presents the design and implementation of 500 VA solar inverter to aid provision of home electricity need through solar energy, especially in rural areas where access to the national grid is not available. The oscillator circuit of the inverter consists of a SG3524 integrated circuit and two NPN transistor drivers powered directly by a 12 V battery through a switch. The actual construction was done on a Veroboard and enclosed in a metal casing. The testing of the solar inverter system was carried out in the month of July, using a tilted solar module. The result of the study shows that the inverter functions efficiently with 12 V deep cycle battery with threshold capacity rating of 62 AH which can sustain steady output of 220-240 V to external load for more than four hours.