Soft Computing Based MPPT Controller for Solar Powered Battery Charger Under Partial Shading Conditions

Solar irradiations received by the PV panel is blocked by a moving or non-moving object is known as partial shading condition. The solar panel power output under partial shaded will be a maximum only if the panel voltage is maintained at the Global Maximum Power Point. The GMPP can be determined from the Power-Voltage characteristics of the partially shaded solar panel and this voltage is called optimum voltage. The battery charging may require a voltage different from the optimum voltage. Therefore, a GMPPT Global Maximum Power Point Tracking CUK converter is employed that maintains partially shaded solar panel voltage at optimum value and buck or boost the solar panel voltage to a value required for battery charging. The objective of this work is to develop solar based battery charger using CUK converter with Maximum Power Point Tracking under partial shaded condition by Grey Wolf optimization algorithm The simulation of the partially shaded solar panel fed CUK converter for battery charging applications is performed in MATLAB - SIMULINK. The CUK converter in the battery charging system is basically a buck-boost converter that employs a single power switch. Duty cycle of gate pulse to power switch decides the power drawn from partially shaded solar panel. Therefore, the duty cycle is determined for GMPPT using Grey Wolf optimization algorithm which can track the GMPP very fast for fast changing irradiances. The simulation is performed for charging 5.8 AH, 48 V Lithium- Ion batteries.