考虑触头结构的气体绝缘母线热网络模型

Gas Insulated Bus Thermal Network Model Considering Contact Structure

为实现对气体绝缘母线(GIB)过热性故障的及时诊断,该文提出一种GIB设备触指和外壳温度快速精确计算方法。该方法基于热电类比和传热学原理,建立包含触头结构的GIB热网络模型。利用圆盘接触的单热流通道(CMY)模型计算了触指与导电杆、基座之间的接触热阻,通过有限元数值模拟试验获取GIB各部件表面的非线性对流换热热阻及辐射换热热阻。利用GIB温升原型物理试验对基于热网络模型的GIB触指和外壳平均温度计算结果进行了验证。结果表明:在不同测试电流作用下,热网络法的计算速度约为有限元法的34倍,GIB外壳及触指温度热网络模型计算值与实测值之间误差最大为9.5%,最小为0.2%,验证了所建立的气体绝缘母线热网络模型的有效性。该模型可用于快速评估GIB设备外壳及触指温度,为GIB设备的热设计和温升状态监测提供了一种有效的分析方法。

In order to achieve timely diagnosis of overheating faults of gas insulated bus bars(GIB),this paper established a GIB temperature rise thermal network model including contact structure based on thermoelectric analogy and heat transfer theory.The contact thermal resistances between the finger,the conductive rod and the substrate were calculated by the disk-contact single heat flow channel model(CMY model),and the nonlinear convective heat transfer resistance and the radiant heat transfer resistance of GIB were obtained by finite element numerical simulation.The physical tests of steady-state temperature rise of GIB under different test currents were carried out.The results show that:under different test currents,the calculation speed of thermal network method is about 34 times that of finite element method,the maximum temperature error between the calculated and measured values is 9.5%,and the minimum is 0.2%,which verifies the thermal network model of GIB.This model can be used to quickly estimate the finger and shell temperature of GIB,providing an effective analysis method for GIB thermal design and temperature rise monitoring.