Research on Control Strategy of Direct-drive Permanent Magnet Synchronous Wind Power System

Abstract

Aiming at the problems of low power generation efficiency and large grid-connected current harmonics of the grid-side converter in the direct-drive permanent magnet synchronous wind power generation system under traditional proportional integral (PI) control, a grid-side converter quasi-proportional resonance (Q-PR) control strategy is proposed. Taking advantage of the Q-PR controller's ability to control the alternating current (AC) input signal without static error in the static coordinate system, it realizes the rapid response of the system and unit power factor control, reduces the grid-connected current harmonics, and keeps the direct current (DC) bus voltage stable. This paper builds a simulation model of the power generation system in MATLAB/Simulink, and does a harmonic spectrum analysis of the grid-connected current. The simulation results show that the Q-PR control strategy proposed in the article meets the grid-connected control requirements of the wind power generation system. The system has fast response speed and good stability. Compared with the traditional PI control, the current harmonic content is less.