A Modified perturb-and-observe-based Maximum Power Point Tracking Technique for Photovoltaic Energy Conversion Systems

[摘要] One of the most widely used maximum power point tracking (MPPT) methods in photovoltaic systems (PVSs) is perturb and observe (P&O) method due to its simplicity, ease of use, and acceptable performance. However, it has two important drawbacks: (1) the undesirable fluctuations around the maximum power point (MPP) under steady-state environmental conditions; (2) the tracking deviation under sudden change as well as gradual variation in the irradiation conditions. This paper proposes a simple modified P&O-based MPPT method for PVSs in which the perturbation size is adaptively determined in such a way that the convergence speed to the MPP is increased and the undesirable oscillations around the MPP are decreased. In addition, the direction of the perturbations is determined on the basis of incremental conductance MPPT method so that the proposed algorithm is capable to extract the maximum power from the PVS, even under sudden or gradual variation in solar irradiation. The validity and effectiveness of the proposed algorithm are investigated using time-domain simulations in the MATLAB® software environment.

[学科分类] 自动化工程

[关键词] Photovoltaic (PV) system;Maximum power point tracking (MPPT);Perturb and observe (P&O);Adaptive perturbation size;Sudden irradiation change;Irradiance gradually varying