含分布式电源的配电网停电风险快速评估

Fast Assessment of Power Failure Risk in Distribution Network Containing Distributed Generation

大量分布式电源(distributed generation,DG)接入配电网导致系统元件数量的增加和系统状态数目的增大,为停电风险评估在含DG配电网中的实施带来困难。为此,提出一种基于设备随机故障的含DG配电网停电风险快速评估方法。为加快评估速度,在系统状态抽样环节引入拉丁超立方抽样技术(Latin hypercube sampling,LHS),通过对配电网各系统变量实施分区、抽样、排序的方式得到用于停电风险评估的系统状态;通过定义负荷点的贡献度与消耗度2个孤岛划分参量,削弱了孤岛划分算法中负荷点接线结构对算法快速性的影响,进而提出了能同时满足快速性和精确性要求的孤岛划分方法。从充裕性角度建立了配电网停电风险的指标体系,并制定了相应的风险评价标准。算例结果表明,提出的快速评估方法能反映含DG配电网的停电风险程度,可为电网规划及运行人员提供参考。

A large number of grid-connected distributed generations （DGs） have brought increase of components’ number and system states of power distribution network, which makes risk assessment of distribution network containing DGs difficult. Therefore, based on components’ stochastic failures a fast power failure risk assessment method for smart distribution network is proposed. In order to speed up assessment, Latin hypercube sampling （LHS） technology is adopted in the process of system states sampling. Through partitioning, sampling and ranking of system variables, system states used for power failure risk assessment can be obtained. On the basis, an island partition strategy which satisfies the requirement on quickness and accuracy is proposed, and two new parameters, respectively named load point contribution and consumption, are defined which can weaken the impact of load points’ connection structure on algorithm rapidity. The index system of power failure risk and power failure risk assessment standard are established. The simulation results show that the proposed method can provide power failure risk degree which can give reference for planning and operating staff.