Control And Optimal Operation Of Micro-grid With Wind Power

The development of human society can not be separated from energy. With the aggravation of the energy crisis, the renewable energy has been paid more and more attention by all countries.The wind power generation technology has become the most mature and widely used renewable energy technology. But wind power output power vary with the change of wind speed,so its volatility, intermittent and randomness have a bad impact on the power grid. In order to ensure the safe and stable operation of the power system, wind power capacity connected to the grid have been specific limited. In order to improve the wind energy utilization ratio, all the countries in the world are carried out active research, trying to find out new ways to improve the wind power penetration ratio. Distributed power generation technology can achieve energy gradient complementary, improve utilization rate of wind power effectively.With less pollution, flexible installation,and low line loss, the distributed power generation technology has been the attention of the countries all over the world. With the development of power electronic technology,Micro-grid concept arises at the historic moment, become a hot-spot in the field of wind power soon.This paper studied Micro-grid with wind power,based on the summary of the types of energy storage system, the way of access and the composition of the Micro-grid,and the structure of the system.First, this paper analyzed the fluctuation characteristics of wind power in different time scales by using wavelet transform based on the the measured wind turbine output data with interval 1seconds and 30 seconds.Then the paper analyzed the structure of the Micro-grid, and established mathematical model for various parts of the Micro-grid. After that,the capacity ratio problem of wind power units and battery energy storage was studied, the allocation algorithm with economic cost as the goal function was proposed, the constraints was set,a kind of configuration principle and method was proposed and the effective of the proposed configuration method was verified through the examples.Afterward, the Micro-grid model was established in Matlab/Simulink and the multi time scale characteristics of battery energy storage was discussed.Finally, the simulationresearch for on and off grid operation, and frequency stability and voltage stability of Micro-grid under load fluctuation was analyzed. The simulation results showed that the model was effective.