Photovoltaic non-linear medel solution and improved P&O method for MPPT

For maintaining photovoltaic (PV) generation system at maximum power point, it is necessary to calculate the parameters of PV cell model precisely. The modified expressions for the single diode equivalent circuit parameters of PV cell are derived based on the four basic electric parameters provided by manufacturer. An improved perturbation and observation (P&O) method is proposed to achieve the maximum power point tracking (MPPT). A simulation system based on a MSX-60 PV panel is constructed by Matlab/simulink to predict the output characteristics of PV panel, which are compared with those of the traditional P&O and the incremental conductance (INC) methods. The simulation results indicate that the modified parameter expressions of PV cell are more precise and the PV panel controlled by adopting the improved P&O method has higher tracking efficiency.