Author : Mapari S.K. and Borole Y.D.

Solar resource is freely available so government is trying to implement the use of Solar panels as an energy source in rural and sub urban areas for lighting the street lights, but the battery used to store the power gets affected due to overcharging & discharging. Charge controllers are usually installed in Solar Home Systems to protect batteries (from over charging and discharging) and to implement proper buck and boost charging techniques (e.g. Maximum Power Point Tracking etc.).Some MPPT controllers have also been developed to incorporate multiple charging sources (e.g. Main-Grid or PV panels) (W.Xiao,N.Ozog et al , 2007;Zheng, L. Wang et al, 2011). However, these controllers lack proper charging techniques to ensure efficient use of multiple charging sources. Also due to improper charging algorithm there might be unnecessary or insufficient charging of batteries. This paper presents a design of peak usage time and prediction algorithm based battery charging technique which enables intelligent battery charging decisions (E. Koutroulis, K. Kalaitzakis et al, 2001) and improve the battery life and efficiency of battery. Specifically, the system will use Mains charging only when Solar charging is insufficient. Also, the system will decide when to preserve battery and use Mains as direct drive loads. These decisions are made to utilize more solar energy and less Mains electricity while maintaining high reliability and improve efficiency. The decisions will be based upon battery’s state which is calculated using various data such as peak usage time, solar voltage, solar current, load’s power demand, batteries’ specification etc. the system designed with this technique has better performance over other solar charge controllers. It will calculate efficiency of system with the help of solar voltage and current. This paper also presents hardware designs to implement algorithm.

Keywords: Solar System, PV panel, Peak usage time, prediction-based, hybrid charge controller

Article published in International Journal of Current Engineering and Technology, Vol.4, No.6 (Dec-2014)