Research on Idle Load Grid-Connected Control Strategy of Variable Speed Constant Frequency Wind Power Generation System

The doubly-fed wind turbine, recognized for its wide operational speed range, high energy utilization rate, soft grid connection, and adjustable power factor, represents a mainstream choice in wind energy technology. This paper focuses on the modeling and simulation of a variable speed constant frequency doubly-fed wind turbine system. The research encompasses the development of a mathematical model for the grid-connected doubly-fed generator, the design of a control strategy based on stator flux-oriented vector control for the idle load grid-connected mode, and the simulation of the model using S-functions in MATLAB. The simulation results demonstrate that the synchronization time of the stator voltage with the grid side voltage is extremely brief during the idle load grid-connection process. Moreover, the system is capable of maintaining stator voltage synchronization with the grid side voltage even in the event of sudden wind speed changes. Furthermore, even with a voltage difference of 0.1V between the stator and the dq-axis on the grid side, grid connection can be achieved within 0.2 seconds.