A Solar PV Retrofit Solution for Residential Battery Inverters

Frequent power cuts necessitate the use of battery fed inverters in many homes and small industries in countries like India. Due to several charge and discharge cycles, the batteries have a typical life of 3 - 4 years. In this paper, a solar PV based retrofit solution is proposed which can be used along with these inverters. This solution uses a bi-directional DC to DC converter which charges and discharges the battery in the presence and absence of solar radiation respectively. The converter has been implemented using a simple add-on circuit with the main battery inverter. The proposed solution has the potential of providing high-quality power, grid connectivity, energy saving and enhancing the battery life. An analysis showing the effective energy saving using the proposed scheme has been presented. Simulations and experimental results have been obtained, and some representative results are included.