Study On Model Establishment And Control Strategy Of VSCF Wind Power Generation System

The study on variable-speed constant-frequency (VSCF) wind power generation system has become the focus of wind power in its own good control performance and high efficiency in the regulation. Nowadays, doubly-fed induction generator is the most widely used for wind farms in China. Hence, this dissertation analyzes the theory of DFIG and its operating characteristics firstly, which establish a theoretical foundation for succeeding study. Then, according to the generator mathematical models and the control principle of vector-oriented, the simulation model is designed in PSCAD/EMTDC and the related control strategy of power and pitch angle are studied in this basis. In addition, the simplex method has been used for the PI Parameters modification of DFIG control system model to improve the system dynamic response characteristics. At last, an equivalent wind farm model is proposed in this paper based on the operation and the internal loss characteristics of the wind farm. The collective response of the wind farm is represented by one single equivalent wind turbine and this greatly simplifies the size of simulation model.