Simulation and Experimental Investigation of a Smart MPPT based Solar Charge Controller

Abstract

ABSTRACT This paper presents the concept of a maximum power point tracking (MPPT)-based solar charge controllers (SCC) for charging a battery in stand-alone solar photovoltaic (SPV) systems. An SCC is a battery charge regulator that is connected in between the SPV panel and the battery, the primary purpose of the SCC is to regulate the charging of the battery so that it charges correctly and more importantly it is not overcharged. Nowadays mainly two types of SCCs are in use, one is the pulse width modulation (PWM)-based SCCs and the other one is MPPT-based SCCs. Although PWM-based SCCs may get the job done but they have very low efficiency as compared to MPPT-based ones and thus waste a lot of SPV power. This fact has been analyzed in our report by executing the simulations for both the charge controller types and the efficiency of PWM was found to be only 65% where as that of the MPPT based is 94%. In this prototype model, we have implemented MPPT-based SCC along with one Wi-Fi module for monitoring the battery voltage, current, PWM pulses and battery status on smartphone. The user also gets notified about the battery status, whether the battery is charging or it is over charging. If the SPV voltage is more than 12 V the relay disconnects the battery from the SPV cell and a notification regarding this is given to the user. All these features make the prototype versatile and user-friendly.