A Novel MPPT Strategy Based on Decentralized Control in subDPP Systems

This paper presents a simple decentralized control technique based on relative gain array with an outside-in maximum power point tracking strategy (MPPT) for submodule differential power processing systems. The proposed strategy can achieve at least twice the convergence rate as the traditional one-way MPPT strategy. Furthermore, the proposed control technique has better utilization of control inputs and scales well in a long photovoltaic string. Moreover, the resultant symmetrical transfer functions enable easy controller tuning in a long string. The effectiveness of the strategy is validated by PLECS simulation.