A variable-weather-parameter MPPT control strategy based on MPPT constraint conditions of PV system with inverter

摘要

The maximum power point (MPP) may be not tracked successfully because of the constraint conditions among some circuit parameters. To solve this problem, in this paper, the maximum power point tracking (MPPT) constraint conditions of photovoltaic (PV) system with inverter are found by analyzing its integrated mathematical model. Based on them, a variable-weather-parameter (VWP) MPPT control strategy is proposed. By the use of it, the complex control for the combination of the DC/DC converter and inverter can be avoided, which ensures the lower hardware cost, shorter design period and better MPPT performance. Finally, some simulation experiments show that the proposed MPPT constraint conditions are accurate and reasonable regardless of the varying irradiance, temperature or load, verify that the proposed MPPT control strategy is feasible and available to track the MPP successfully, and illustrate that there is a better MPPT performance than the conventional perturb and observe (P&O) method and fuzzy control method.