Efficient perturb and observe algorithm for photovoltaic maximum power point tracking and drift avoidance using SEPIC converter

Abstract

Maximum power point tracking is a commonly used technique for extracting maximum possible power from solar photovoltaic (PV) systems under all conditions. Various methods used for implementation of MPPT algorithm, out of those methods, perturb and observe (P&O) is very popular and commonly using method owing to its simplicity, easy implementation and highly efficient nature. However, P&O algorithm has disadvantage that it suffers from drift phenomenon in which during sudden change in atmospheric conditions, the algorithm drifts away from the maximum power point (MPP). This paper proposes modifications in the conventional P&O algorithm to overcome the drifting of MPP during suddenly changing atmospheric conditions. This algorithm takes change in current into consideration along with change in voltage and power and is verified using MATLAB/Simulink. DC/DC control is achieved using SEPIC converter and simulation results of the proposed algorithm show that the system can track the MPP in transient whether conditions and drifting is avoided.