Research On The Effect Of Grid-Connected Wind Farms On Power System Stability And Improvement Measures

Large-scale wind power generations connect to the power system is one of the feature of modern power system in many industrialized countries. Up till now wind power generation is the largest source that environment-friendly power generation. Comparison other environment-friendly power generation wind power generation is the peak efficiency.Wind power generation is a replacement technology has future possibilities,but it affect the power system stabilization.It is a important problem that need to solve.The paper discuss some problem that wind power system connect to the power system from the following aspects:First, A survey of some problem that wind power generation connect to the power system. For instance, centralized wind power generations are more stable than single wind power generation; grid-connected wind farms affect the power system stability.; grid-connected wind farms affect the protection system in power system; grid-connected wind farms have some technically demanding.Second, up-to-date wind farms mostly adopt variable speed constant frequency wind turbine. Doubly-fed variable speed constant frequency wind turbine is extensively used and is mainstream.The paper by discussing doubly-fed variable speed constant frequency wind turbine construction, analyse it's static model,dynamic model and the property of power regulation. Finally it is verified by the results of PSCAD simulations.Third, discussion the static stability, dynamic stability and transient stability are between doubly-fed variable speed constant frequency wind turbine grid interconnection and the power system. Analyse the effect of doubly-fed variable speed constant frequency wind turbine grid interconnection to the protection system in the power system. Finally it is verified by the results of PSCAD simulations and numerical examples.In the end, discussion it should take measures that line protection and primary synchronous generator in the power system. Analyse some ways to enhance system reliability and adopt FACTS flexible exchange transmission can slove some problem that wind farms connect to the power system.