A Staggered-Phase Off-Oscillation Photovoltaic LMPPT Algorithm for Suppressing the Improper-Perturbation

In order to deal with the problem of three-level oscillations and improper perturbation of common algorithm in photovoltaic (PV) system. We propose a staggered-phase off-oscillation photovoltaic LMPPT algorithm for suppressing the improper-perturbation. We stagger the perturbation time to forbid PV modules disturb simultaneously, applying Perturbation and Observation (P&O) in maximum power point tracking (MPPT) and least power point tracking (LPPT) control algorithm and maintain the intermediate level of three-level oscillation. It solves the problem of mutual interference of multi-modules during the perturbation process, finding the optimum operating point quickly and eliminates the three-level oscillation. Finally, experimental prototype is set up, all experimental results demonstrate the feasibility and advantage of our algorithm.