基于网络连通性分析的直流偏磁分布关键站点评估

Identification Method for Critical Nodes of DC Bias Current Distribution Based on Network Connectivity

针对变压器直流偏磁及其效应问题,提出了一种辨别影响变压器直流偏磁电流分布的关键变电站点的方法:一方面,从系统结构出发,构建偏磁电流连通重要度指标,以反映对偏磁电流流通路径起关键作用的变电站节点,另一方面,从系统直流分布的角度,定义了节点–节点影响度指标的概念,以此衡量变压器直流偏磁效应对系统的作用严重程度,将上述两方面结合,进行了偏磁电流的传播机理及关键站点的识别方法的研究。采用实际工程案例进行分析,结果验证了该方法的可行性。研究成果可望为实际工程提供变电站直流偏磁治理的理论依据和有用参考。

To solve the problem of DC bias and bias effect of a transformer, a method for identifying the key substation stations that affect the DC bias current distribution of transformers is proposed. On the one hand, based on the system structure, the importance index of bias current connection is constructed to reflect the bias. The magnetic current circulation path plays a key role in the substation node. On the other hand, from the perspective of the system DC distribution, the concept of the node-node influence degree index is defined to measure the severity of the DC bias effect of the transformer on the system. Combined with the two aspects above, the propagation mechanism of bias current and the identification method of key sites are studied. The actual engineering case is used for analysis, and the feasibility of the method is verified. The research results may provide the theoretical basis and useful reference for DC bias treatment of substation for practical engineering.