Study On The Small Signal Stability Analysis Of Wind Power System

With the wind power generation is gradually increasing in power ratio, wind power has become one of the most promising new energy power generation. Development of the wind power has become an important choice for the sustainable energy strategy of China, "Twelfth Five Year Plan" period, China in Gansu, Xinjiang, Hebei, Jilin, Inner Mongolia, Jiangsu and other places planning and construction of 7 million kilowatt wind power base. By the end of 2013, the world wind power installed capacity reached 318,130,000 kilowatts, China's wind power installed capacity of 77,160,000 kilowatts, accounting for 6.2% of the national installed capacity of generators. When large-scale wind power base centralized access transmission system, which can make the dynamic behavior and stability mechanism of the whole system change significantly. Power system small signal stability issue caused frequent brought huge economic losses to the people, so the small signal stability problem of power system has aroused wide concern.This paper reviews analysis method of power system small signal stability, and operation principle and mathematical model for different types of wind turbines are introduced reasonably in detail. This paper, based on power system simulation software PSAT, analyzes the different types of wind turbine(including constant speed wind turbine, doubly fed induction generator, direct drive synchronous generator) effect on the system small signal stability. The purpose is to select the wind generator which has an relatively positive effect on the system small signal stability. Secondly, this paper analyzes the effect of different DFIG wind farm location on the system small signal stability, and select the DFIG location which may relatively improve the power system small signal stability. Finally, this research analyzes the effect of DFIG penetration on the system small signal stability, and for the the worst stability examples, some measures are given to improve the system small signal stability. By properly reducing the DFIG power factor, the damping of the synchronous machine oscillation, which is near the DFIG wind farm, can be increased. The system small signal stability is improved. The conclusions can be verified by a real power grid.