Research On Available Transfer Capability Assessment Of Power System With Large Wind Farm

With the development of wind power generation technology and intelligent electric grid, many large wind farms are built up in recent years. Because of the fluctuation, the integration of large-scale wind power into the power system will cause voltage fluctuations and bring challenge to the safety and stabilization of power grid and then restrict the scale of wind power development. The wind farms have large capacity, while the power grid construction is weak, many urgent problems should be solved, such as available transfer capability(ATC) assessment, which have important academic and practical significances to transmission system planning, operation and reliability evaluation.In this paper, considering the uncertain factors, the ATC assessment of power system with large wind farms is studied based on Monte Carlo simulation, DC power flow and Linear-programming. The influence of wind farm will be obtained by the comparison of indices.First, the Weibull distribution is used to simulate the wind speed. Then the typical output characteristic curve of wind speed is uses to calculate the output of wind farm considering the fault of wind generators. Then, a series of ATC probabilistic indices are proposed to evaluate ATC, for example, the expected value of ATC, variation of ATC Variation coefficient, duration of ATC not satisfied, probability of ATC not satisfied, the expected value of ATC not satisfied, the contribution coefficients of wind farm to PPANS, the contribution coefficients of wind farm to TDANS, the contribution coefficients of wind farm to EEANS-ATC is studied based on DC power flow and Linear-programming. Through comparing, the influence of wind farm to the grid will be obtained. Finally, the sensitivities of components parameters to ATC indices are calculated so as to find the vulnerability of power system.