Research On Impact Analysis And Control Strategy Of Wind Farm Operation With Interferential Load

Due to the abundant wind resources, solar energy and the support of national policy in some geographic locations, Parts of the national grid have been the characteristic of integrating with concentrated wind power and with high proportion of energy intensive load. Considering the fact of the rapid development of electrified railway in the same area, the intersection between interferential load and wind farms become more and more common, and the problem will become more prominent.In this paper, firstly the author analyses the negative sequence component of the traction load supplied through the mode of AT power, the negative-sequence voltage produced by locomotives is calculated. The cutset method is used to establish multiple ports NORTON equivalence model of local power grid which including wind turbines and traction load. A method to assess the impacts of negative-sequence components on nearby wind power generators due to grid-connected traction load of electrified railway is proposed. When considering the multiple traction load taking turns in phase connected to grid, by analyzing the negative sequence component and phase Angle of the traction load supplied through the different power supply mode, the average negative-sequence capacity of traction load is calculated. The power flow data files and stability data files in PSD-BPA software are used, then the negative-sequence voltages at generators’terminals are calculated by using superposition principle. And the negative-sequence currents flows through wind power generators can be obtained. In the proposed method, the complex process for re-modeling and re-simulation of regional power grid are omitted. Results of calculation examples show that the proposed method is effective.In addition,basing on the model of electric arc furnace and doubly-fed,the simulation experiment of the effects on doubly-fed generators due to arc furnace when the two connected to the same common PCC is implemented.The correlation and sensitivity thesis are used to analyse the simulation data.It is useful for the selection of the access points of wind farm as well as electric arc furnace.Finally, by analyzing the traditional control method under the unbalanced grid voltage, the negative sequence of stator current component is produced. The modified strategy which contains the negative sequence current control is presented.The simulation result indicates that the method can effectively suppress the negative sequence component of the stator current.