基于熵的复杂电网的脆弱性识别与评估

Identification and Assessment of Vulnerability of Complex Power Grid Based on Entropy

电力系统线路发生扰动时会出现潮流转移,电网中的一些脆弱对潮流转移很敏感并且对故障传播起着十分重要的作用,识别出电力系统中关键的线路和节点对于提高电网安全性抑制故障传播有重要意义。根据熵的基本理论,利用潮流熵反映系统的运行的不均一性。考虑线路的承载能力并且结合潮流转移和分布特性建立支路脆弱性模型,根据节点的网络结构和运行状态建立节点脆弱性模型。通过对IEEE39节点进行模拟计算,当节点的潮流分布熵越小时潮流分布越不均匀,节点越脆弱,支路潮流熵越大时,支路越稳定。通过与其他方法比较,本文结论得以验证。

The disturbance occur in power grid causes the redistribution of power flow. Some component in power grid is very sensitive to such redistribution and play a key role in the propagation of fauk. It is of great importance to identify the critical node and line to curb the propagation of fault and fortify the safety of the power grid.Base on the entropy theory, the unevenness of the operational state can be reflected by the power flow entropy.Under the consideration of the load level of each branch and combined with the power flow redistribution and uansfer characteristics,the modal of vulnerable node and line are proposed.Based on the simulation oflEEE39 system,the result demonstrated that the lower the entropy value of nodes the more unstable the node is, the higher the entropy value of branch the more the branch stable.The proposed method can be verified by the comparison between other methods.