Dynamic Step Size Based Maximum Power Point Tracking in PV Systems

The traditional maximum power point tracking (MPPT) algorithms operates with a fixed value of the step size, this operation causes a delayed convergence and more power variations in the MPPT process. The updating of the step size with the distance of operating point from the maximum power point (MPP) helps in controlling the algorithm convergence time. To solve this problem, in this paper, incremental conductance algorithm is modified with the inclusion of dynamic value of step size. In the proposed work, a dynamic step size based incremental conductance (DSINC) algorithm is coined, the step size of this algorithm is not fixed but depends upon the distance of operating point from the MPP, this results in a high value of step size at a point away from MPP and a small value at the point close to the MPP. The implementation of algorithm is carried out on a simple photovoltaic (PV) system consisting of dc-dc converter. The working of the DSINC is compared with the traditional INC to draw a general comparison, the results are obtained by simulating the PV system model in the Simulink platform of the MATLAB.