基于等效热路模型的GIS隔离开关温升计算

隔离开关是电力系统中关键的一次设备。表征设备负载能力的温升,特别是GIS封闭式隔离开关温升的计算在工程上具有重要参考价值。针对GIS隔离开关的热计算,基于传热学基本原理,建立了220 k V三相共箱式SF_6隔离开关等效热路模型,给出了GIS外壳及导体表面的对流换热及辐射换热的计算公式,提出了针对其在运行工况下,考虑环境温度、接触电阻、负荷电流等因素的稳态热场计算方法,计算结果与FEM计算结果的对比分析表明,所提出的模型能有效、快速计算GIS隔离开关正常运行条件下的热点温升,为电力设备的动态增容提供重要参考。

Temperature-rise calculation of GIS disconnecting switch based on equivalent thermal-circuit model

Disconnecting switch is the key primary equipment in power system .Temperature rise , which indicates the load capacity of power equipment , especially the enclosed GIS disconnecting switch , it can be calculated to make it an important reference value in engineering .This paper has built an equivalent thermal-circuit model to calculate the temperature rise of 220 kV three-phase enclosed SF 6 disconnecting switch based on heat transfer theory .The calcula-tion formula of convective and radiative heat transfer between GIS conductor and tank has been given .The calculation method of steady thermal field under operating conditions considering the ambient temperature , contact resistance and load current has been proposed .The comparison between FEM and calculated results shows that the proposed model can be used to acquire the hot-point temperature-rise of GIS disconnecting switch under normal operating conditions quickly and effectively , thus providing an important reference on dynamic capacity-increase of power equipment .