基于节点流量重要度的电网关键节点辨识

当电力系统发生大规模连锁故障的时候,电网中的某些关键节点可能会对故障的扩大起着推动的作用。为了提高关键节点辨识的准确性以及更好地预防大规模连锁故障的发生,本文提出了基于节点流量重要度的电网关键节点辨识方法。该方法通过定义节点传输贡献度指标和节点传输效率,然后基于电网节点潮流传输贡献重要度矩阵,计算各节点的节点流量重要度并进行比较。最后,通过对IEEE 39节点系统和南方某区域电网进行仿真,所得仿真结果表明本文所提方法计算的指标可以定量表征某个节点在潮流传输及其在电网拓扑结构中的重要度,可以有效、准确地辨识出电网中的关键节点,判断它们在交直流电网自组织临界演化过程中的作用,对预防系统向连锁故障临界状态演化有着重要的意义。

Identification of Critical Nodes in Power Grid Based on Node Traffic Importance Degree

Some key nodes in the power grid play an important role in the large-scale cascading failures. In order to improve the identification accuracy of the key node and to prevent the occurrence of the blackout, a new method for identifying the key node based on node traffic importance degree is proposed. The node transmission contribution index and node transmission efficiency are defined by the proposed method, and then the node traffic importance degree of each node is calculated and compared based on the transmission contribution importance matrix of power flow. In the end, the simulation results of IEEE 39-bus system and a southern regional power grid show that the proposed method can quantitatively characterize the importance degree of a node in power flow transmission and electrical topology in the power grid. It has important significance to identify the critical nodes in the network effectively and accurately, and to determine their role in the evolution process of self-organized criticality in AC/DC power grid. It has an important significance on preventing evolution of cascading failure system to the critical state.