Research On Power Flow Calcultion And Optimization Of Power Network With Wind Farms

Wind power has been highly regarded all over the world because of its less investment, less pollution, renewable advantages. Connecting more and more large-scale wind farms to the grid is the main trend in the development of the smart grid. Along with large amount of wind power integrated into the power system, the structure and function of the system will vary, at the same time the original power flow direction trend and transmission power of the line will change, which will do harm to the grid system. The study of power network power flow including wind farms is an important tool for quantitative analysis of the influence caused by wind farms connecting to grid system. Therefore, the power flow calculation of power network that contains wind farms is studied in the paper. On the basis, the problem about power flow optimization of power network with wind farms is studied. Its major task is as follows:1. The power flow calculation model of asynchronous wind turbine generator is established. In the power flow calculation, there are two most common models of asynchronous wind turbine generator,RX and PQ. Sometimes, the model is also treated as PZ. The PQ(V) steady-state model is established with considering the equivalent circuit of Asynchronous wind turbine generator.2.The rectangular form of Newton- Ralph calculation method is chosen for power flow calculation. Then use the MATLAB software M file to write the current program and analyze the system’s voltage level, reactive power demand and the network loss under different output levels of wind farms. The probable range of the grid system is presented in this paper,which is supposed to solve the error existing problem in wind speed forecast.3.The genetic algorithm is improved. The improved genetic algorithm is adopted to optimize the reactive compensating capacitor of distribution network. According to the change of load level and wind farm output level, the optimal design are given respectively. The focuses are on the influence of wind farms integration on the power loss and voltage level of distribution network.