DESIGN AND IMPLEMENTATION OF A MICROCONTROLLER BASED MAXIMUM POWER POINT TRACKING SOLAR CHARGE CONTROLLER

Abstract

Photovoltaic (PV) system is one of the revolutionary renewable sources that are grabbing place rapidly instead of traditional energy sources. Industries are now designing solar roof, solar tree leaves, solar roadways, solar vehicles and even flexible solar cells for clothing. In the meantime, The International Energy Agency (IEA) reports that, last year, renewable overtook coal as the world‟s largest source of new power capacity. Yet, effective power generation or power extraction from renewable sources remain relatively low, and this must rise fast, as people transition to a more green and environment-friendly energy future. The demand or future work is looking for high efficiency, more reliable and low economical price of every components used in a PV system. PV charge controller (CC) is one of the most important parts of a PV system. CC circuit is used to extract the power of a solar panel during its less than optimum conditions. Under reduced incident solar radiation, due to the cloudy weather the low power level supplied by the solar cell normally would not be adequate to operating a load and charging up the storage or battery, but with the presence of the controller circuit, the low power generated by the solar panel would be accumulated to a high enough level to overcome the energy barrier of the battery or the load. In this research, a solar charge controller is designed based on Maximum Power Point Tracking (MPPT) technique. Microcontroller PIC 16F877A integrated circuit (IC) works as control unit, which reduced complexity in the number of electronic components and increased monitoring and regulative functions. The benefit of this charge controller is maximum power tracking capability from the solar panel, as well as customized programmable control unit, remote control and monitoring facility interfacing with smart phone or laptop applications, external device charging unit, Liquid Crystal Display (LCD) for displaying the system status including both of panel and battery voltage, current, power, charging state of battery in percentage and load status. Experimental results demonstrate that proposed MPPT charge controller increase 11% efficiency of 85W, 12V standalone PV systems. Estimated total cost of the CC is BDT 2047 (approximate USD 26).