Direct power control strategy on grid and machine sides of open-winding brushless doubly-fed wind power generator system

Abstract

In order to improve the power quality of wind power generation system, a direct power control (DPC) strategy of open-winding brushless doubly-fed generator (BDFG) system based on dual converters is presented in this paper. The control method is divided into two parts: the grid side converter control and the machine side converter control. In terms of the grid side converter, a model predictive-based SVPWM direct power control(MP-DPC) is used. In comparison with the traditional voltage oriented direct power control(VO-DPC) strategy, the switching frequency can be fixed and harmonic content can be reduced, and at the same time the grid side converter can achieve basically constant DC bus voltage. In the machine side converter, the open winding structure of BDFG is used and the control accuracy of active and reactive powers is improved. The simulation of the proposed control strategy is carried out through Matlab/Simulink software and the simulation results prove the correctness and feasibility of the DPC strategy for the open-winding BDFG system on the grid and machine sides.