基于有限元法的变电站短路电动力引流线偏移故障分析

Research on Fault Analysis of Substation Short Circuit Force-induced Offset of Drain Lines Based on Finite Element Method

近年来,由于短路电动力引起的软引流线偏移已成为影响变电站一次设备安全稳定的重要因素之一。为了科学地应对变电站软引流线的这一固有风险,并掌握软引流线的特性,本文基于一起220 kV变电站发生近区短路故障的情况开展研究。通过电磁学理论计算得到短路电流产生的短路电动力,建立导线动力学特性的有限元仿真模型,计算获得电动力作用下引流线最大摆动位移,明确了电动力导致引流线相间小于临界值发生放电。同时通过有限元仿真计算,分析了不同长度和线径引流线的最大摆动位移变化规律,提出了对应的整改方案。

In recent years,the deviation of soft drainage line caused by short circuit electric force has become one of the important factors affecting the safety and stability of substation primary equipment.In order to scientifically deal with the inherent risk of soft drainage lines in substations and master the characteristics of soft drainage lines,this paper carried out a study based on a 220kV substation short-circuit fault in the near area.The short-circuit electric force generated by the short-circuit current is calculated by electromagnetic theory,and the finite element simulation model of the dynamic characteristics of the conductor is established.The maximum swing displacement of the drainage wire under the action of the electric force is calculated,and the discharge between the drainage wires is defined that the electric force causes the discharge of the drainage wire less than the critical value.At the same time,through finite element simulation calculation,the maximum swing displacement of different length and diameter of the drainage line is analyzed,and the corresponding rectification plan is put forward.