| With the excellent characteristics such as higher efficiency of energy converting, wider speed range and better power quality, and the ability of adjusting the active and reactive power of the power system, doubly fed induction generator (DFIG) has become the mainstream in the world. On the research of wind farm, optimum analyze always are hot spot in power system containing wind farm. This thesis mainly described the optimal reactive power (OPF) and the reactive power optimization during the operation of power grid containing the large-scale DFIG wind farm. The wind power penetration conditions and power factor regulation have been discussed. An improved optimization algorithm and the suitable objective function considering the DFIG wind farm is proposed, and the wind farm’s influence on the operation of power system in OPF as well as the reactive power optimization is studied. This ways make DFIG wind farm much better to operation and economy in power system. Combined with artificial bee colony (ABC) algorithm and hybrid ABC algorithm, the study in the thesis achieves good results. The main contents are as follows:Firstly, the model of OPF considering DFIG wind farm is built. The steady-state model of DFIG including the equation of active power, reactive power and voltage is described. The model of OPF containing DFIG wind farm is built by the power flow analysis of all world To improve the optimization, the ABC algorithm is introduced to combine with the adaptation strategy and Boltzmann selection strategies.For on thing, the influence of DFIG wind farm on OPF of the power system is analyzed under the conditions of different of wind power penetration and power factor. The output of conventional power plants can be reduced when the large-scale wind farm is connected to the grid, and thus can obtain the target of economic operation. In high wind power penetration, the DFIG reactive power is changed due to the power factor regulation, and hence can reduce the power loss, which can contribute to ensuring the stability of the voltage of point of common coupling (PCC).The simulation result shows that the operation of the DFIG under high wind power penetration and high wind speed is flexible in the power system. Therefore, the use of conventional power plants can be reduced. But this analysis is lack object function including the operation of wind farm can reduce power loss and compensation equipments.The optimization is short at wind farm of different power factors.The reactive power optimization of DFIG wind farm is analyzed based on hybrid ABC algorithm which base on Boltzmann selection strategies and adaptation policies. Owing to the above reason, DFIG only one power factor is studied, and lack power system operation including wind farm in the different power factor. The reactive power optimization is analyzed in leading and lagging phrase operation respectively, and the hybrid ABC algorithm is used to solve the problem. The result shows that the voltage stability can be ensured in0.98leading phase operation under the reasonable allocation of DFIG wind farm; in0.98lagging phase operation, the parallel operation of the DFIG wind farm can contribute to reducing the power loss and the use of compensation equipment, which can ensure the economic operation of the power system. The research also shows that with a faster convergence speed and a better optimization result, hybrid ABC algorithm proved a preferable one compared with the traditional ABC algorithm.On the research, DFIG power factor regulation is studied, power system including wind farm can have effective operation in the different of wind power penetration. |
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