A modified MPPT control loop for PV/battery-charging system using PI controller optimally tuned with GA

摘要

In this study, a stand-alone photovoltaic (PV)/battery-charging system is proposed to efficiently charge a lead-acid battery with the available maximum power from the PV array. The relative sizing of the battery characteristics with respect to the PV array characteristics is indicated. The maximum-power-point (MPP)-tracking operation is achieved through developing a new control loop, which is based on using the incremental conductance algorithm and the PI controller. The parameters of the PI controller are optimally tuned using the genetic algorithm (GA) by minimizing the integral of squared error and settling time. The proposed system was simulated twice by using MATLAB-SIMULINK and by writing the appropriate M ATLAB code in an M-file. The SIMULINK model was designed to investigate the performance of the proposed system, whereas the M-file model was designed to be used with the GA tool under MATLAB software, to optimally tune the PI controller. The simulation results indicated a rapid tracking capability for the PV array MPPs and a good matching between the PV array and the battery under various charging conditions.