Study Of Reactive Power Compensation Methods In Wind Power Collection Areas

The burning of fossil fuels has led to the increasing pollution to the air,resulting in the deterioration of people's living environment.With the innovation of science and technology and the progress of the Times,scientists and technicians have gradually regarded the clean energy as the main object of energy market and development in the future.However,with the large number of wind power grid connected,a lot of problems have occurred,and the stability of the grid has been challenged.The wind power grid problem is actually the voltage stability problem,and the power compensation of the reactive power is the major determinant of the voltage problem.Current limiting condition of grid connected wind farm is the reactive power compensation problem,and the reactive power compensation problem is to improve the network voltage,which is to reduce active power losses in the transmission line process,and let the voltage stability of network achieve the grid standards.In general,there are many reactive power compensation measures: such as the wind turbine provides reactive power,capacitor / reactor switching,adjustment of transformer tap,return Static Var Compensator(SVC)/ Static Var Generator(SVG),et al.The research from the principle of reactive power compensation equipment,carries on reactive power compensation of wind farm through their respective control manners,and the characteristics of several reactive power compensation equipment are analyzed and compared.Based on wind power cable collection area,the voltage stability evaluation index of large-scale wind power grid is put forward.The simulation results show that the L index can judge the stability margin of wind power set voltage in large-scale wind power collection areaAccording to the study that reactive power optimization control model of current wind farm has not established a complete set,a control algorithm is proposed for wind collecting area of reactive power optimization,based on the coupling and complementation of the above several reactive power compensation measures.Analytic hierarchy process is used to assign weights to multiple objective functions,and restrains that functions.On this basis,the primal dual interior point method is proposed to solve the reactive power optimization.The closed loop control is carried out through the relationship among the compensation equipment of collection station and reactive power compensation of wind farms and wind turbines to synthetically compensate reactive power.Voltage is coordinated and managed in wind collecting area,and this algorithm is calculated and comparatively analyzed to find out the optimal solution.A wind collecting area in Hami is taken as an example for modeling and verification analysis,and the comparison of several reactive power mode analysis verifies the rationality and feasibility of the proposed control algorithm.And then,it establishes the foundation for the unified and coordinated reactive power and voltage control for wind farm,wind farms and power grid.