随着大规模风电接入电网,风电功率的随机性与波动性以及多风电场出力的相关性使得电力系统的运行与调度面临着新的挑战。引入经验Copula函数表征多风电场联合出力分布;对风电的波动性进行建模,利用ksdensity函数拟合风电功率波动量,通过逆变换抽样的方法生成符合风电随机性和波动性的场景集合;生成基于经验Copula函数的多风电场出力动态场景,并将其应用于含多风电场的电力系统随机机组组合问题的求解。算例结果验证了所提风电波动性建模方法的有效性与动态场景生成方法的可行性,同时提高了含多风电场电力系统运行的经济性。
With the large-scale integration of wind power,the randomness and fluctuation of wind-power and the correlation among multiple wind farm outputs bring new challenges to the operation and dispatch of power system. An empirical Copula function is introduced to characterize the joint output distribution of multiple wind farm. The fluctuation of wind power is modelled and fitted with ksdensity function,and the inverse transform sampling is applied to generate a scenario set that conforms to the randomness and fluctuation of wind power. The dynamic output scenarios of multiple wind farms generated based on the empirical Copula function are applied in the stochastic unit commitment of power system with multiple wind farms. Results of case study validate the effectiveness of the established wind power fluctuation model and the feasibility of the proposed dynamic scenario generation method. Its application in the stochastic unit commitment enhances the operational economy of power system with multiple wind farms.