基于外壳热分布的气体绝缘母线温度计算模型

气体绝缘母线在运行过程中负荷电流和外壳涡流将引起设备发热,其温升特性是表征气体绝缘母线运行状态的重要指标。文中基于传热学原理和热电类比法,将126 kV/2 kA户内型三相共箱式气体绝缘母线内部传热过程等效为一个简单的集总参数热路,考虑导体热容、接触电阻、导体和外壳换热系数以及分别与SF_6气体之间的非线性热阻等因素,提出了气体绝缘母线动态等效热路模型。并设计了三相气体绝缘母线温度测量试验,将模型计算结果与试验结果进行对比分析,验证了气体绝缘母线动态热路模型的准确性和有效性,并通过热路模型得到了外壳与导体的对应温升曲线。

Thermal-circuit Model of Gas Insulated Bus Temperature Based on Heat Distribution of Tank

The load current and shell edgy of GIB will incur equipment heat during the operational process and its fea-ture of temperature rise is an important indicator of operating state of the characterization GIB.Based on the principle of heat transfer and hot analogy method, the heat transfer process in 126 kV/2 kA three-phase enclosed GIS bus bar is equivalent to a simple thermal circuit of lumped parameter, considering the heat capacity of the conductors, the coeffi-cient of heat transfer and nonlinear thermal resistance between the conductor and the tank respectively with the SF6 gas, and the equivalent thermal circuit model of three-phase enclosed GIS bus bar is established in this paper.The temperature measurement experiment of three-phase enclosed GIS bus bar is designed, the calculation results of model are compared with the experimental results, and the accuracy and effectiveness of the dynamic thermal-circuit model of gas insulated bus is verified, and the corresponding temperature rise curves are obtained between the shell and the conductor by the thermal circuit model.