Maximum Power Point Tracking Charge Controller Using Modified Perturb and Observe Algorithm for Lead Acid Battery

A study was undertaken on development of a modified perturb and observe algorithm for maximum power point tracking (MPPT) charge controller. This MPPT algorithm was developed in Matlab/Simulink environment, using three-state charging method for improved battery charging with higher efficiency. A buck topology was utilised as a DC-DC converter for charge controller implementation. The maximum power of the photovoltaic panel was tracked by a modified perturb and observe algorithm. The battery charge controller charged a lead-acid battery using a three- stage charging strategy including the bulk charge, constant voltage (absorption charge), and float charge stage. The performance analysis of Simulink model was carried out by maximum power point tracking performance, battery charging performance, and overall charge controller efficiency performance. The performance results indicated that the maximum power point tracking was capable to track to the maximum power of PV panel at any solar irradiance variation with power tracking efficiency up to 98 per cent. The efficiency of overall charge controller was up to 98.3%, which matched many high-end commercial charge controller product specifications.