An Improved Multistage Variable-step MPPT Algorithm for Photovoltaic System

Abstract—This paper presents an improved multistage variable-step incremental conductance method to achieve the maximum power point tracking (MPPT). Compared with the traditional variable-step incremental conductance method, this improved algorithm optimizes the selection of the step size so that the tracking of the maximum power point is more quickly and the steady-state performance is better. Furthermore, the algorithm can still guarantee the quickness and accuracy of MPPT when the environmental conditions change suddenly and tremendously. At last, matlab simulation was applied to compare the characteristics of multistage variable-step algorithm with that of the other. And the simulation results verified that the improved algorithm has better dynamic and steady-state performance. Keywords-photovoltaic system; MPPT; incremental conductance algorithm; boost circuit I