基于信息熵的大型电力系统元件脆弱性评估

现代大规模电力系统面临着多种不确定性因素,它们给系统带来的扰动已成为系统安全运行的主要威胁之一。针对这一问题,提出一种大型电力系统元件脆弱性评估的新方法:在改进信息熵的基础上,结合含风电电力系统的灵敏度分析及支路容量裕度,研究节点扰动功率安全转移的分布信息,建立衡量节点抗扰动能力的节点脆弱性评估指标;在此基础上,通过补偿法将支路开断转化成两端节点的虚拟注入功率扰动,并采用熵权法将其与节点脆弱性评估结果相结合,提出支路脆弱性综合评估方法。通过IEEE 300节点系统算例,验证了方法的快速有效性,同时分析了影响系统关键元件脆弱性的因素,为电力系统中的误差控制和运行管理提供了参考。

Large-scale Power System Components Vulnerability Assessment Based on Entropy

The modern large-scale power system is confronted by many kinds of uncertainty factors, the disturbance brought by which has become one of the major threats to safe operation of the system. In view of this problem, a new method of large-scale power system component vulnerability assessment is proposed. Based on the improved entropy and by referring to a sensitivity analysis of the wind power system and branch capacity margin, the distribution information on disturbance power safe transfer is investigated to establish the node vulnerability assessment indicator for measuring the ability of node to resist disturbance. On this basis, the branch outage is translated into virtual power injection disturbance on the two-terminal nodes by the compensation method. The branch vulnerability is then assessed with the entropy weight method by combining with node vulnerability assessment. Results of an IEEE 300-bus system case study have validated the effectiveness and quickness of the presented method. The factors that influence the key element vulnerability are analyzed, providing reference for error control and operation management in power systems. This work is supported by State Grid Corporation of China (No. dz71 13 036).