Research on Maximum Power Point Tracking Strategy for Direct-Drive Permanent Magnet Synchronous Wind Turbine Generators Based on Double Closed-Loop Control

Abstract

To maximize the efficiency of wind energy utilization, a maximum power point tracking (MPPT) strategy based on optimal torque control is adopted to realize the control of the permanent magnet synchronous wind power generation system. First, the structure of the permanent magnet direct-drive wind power system and the basic principle of MPPT are elaborated, and the optimal power-speed relationship is derived. A system model composed of a wind turbine, permanent magnet synchronous generator (PMSG), uncontrolled rectifier, and boost step-up chopper circuit is constructed. To verify the effectiveness of the strategy, a system simulation model is built on the MATLAB/Simulink platform. Simulation results show that when the wind speed is constant, the DC-side voltage can be stabilized. When the wind speed increases or decreases, the control strategy can track the maximum power point of wind energy according to the wind speed change, maintaining the wind energy utilization coefficient at a high level.