本文建立了电力市场环境下的概率最优潮流模型,并采用基于对称采样策略的无迹变换方法求解。模型中考虑了新能源出力、负荷和发电商报价的不确定性,揭示了概率性背后隐藏的市场规律和系统运行的薄弱环节;无迹变换方法通过非线性变换传递概率信息,引入比例及高阶信息参数以减小局部效应及高阶项误差,而且对随机变量的相关性影响进行了分析。IEEE30和118节点系统计算结果表明无迹变换方法实现简单高效,可精确求解电力市场的概率最优潮流问题,输出的运行特征量统计信息可为评估系统的市场运行状况提供更为可靠全面的参考。
In this paper,a probabilistic optimal power flow analysis model under electricity market environment is proposed,and is solved by unscented transform method based on symmetric sampling strategy.In order to reveal the market laws and the weaknesses of the operating system by considering probability,the uncertainties of renewable generation output,load demand and bidding are taken into account in the proposed model.In addition,probability information is transferred through nonlinear transformation by using unscented transform,in which the ratio and high-order information parameters are introduced to reduce the local effect and high order errors,and its correlation impact on stochastic variables have been analyzed.Numerical results of IEEE30-bus and 118-bus test systems show that the implementation of unscented transformation is simple and efficient,can accurately deal with probabilistic optimal power flow problem of electricity market,and the output statistic information of operation characteristics can provide more reliable,comprehensive references for evaluating operation status of electricity market.