The current research on maximum power point tracking (MPPT) methods for photovoltaic power system application is reviewed. In order to solve the tradeoff between the steady-state efficiency and dynamic efficiency for the conventional MPPT algorithms, this paper proposes an improved β-based variable step MPPT method. Based on the curve of b-V, the proposed method utilizes two different scaling factors for the solar irradiation increasing and decreasing. Therefore, the proposed method realizes the fast tracking MPP and eliminates misjudgments during the transient stage. Furthermore, the proposed method also realizes zero oscillation during the steady-state stage. In order to show the advantages of the propose method, the simulation analysis of main MPPT methods is carried out in Matlab/Simulink. Furthermore, an experimental prototype by using dSPACE and Solar Array Emulator is built and tested. The simulation and experimental results verify the advantages of the proposed algorithm including zero oscillation in steady state and fast tracking for dynamics. This work is supported by National Natural Science Foundation of China (No. 51407145) and the State Key Laboratory of Electrical Insulation and Power Equipment (No. EIPE15203).