体绝缘组合电器（Gas Insulated Switchgear，GIS）母线的可靠性与温升直接相关，热故障的发生严重影响了电网的安全可靠运行。在GIS热故障中，因接触不良造成的占有很大比例。目前GIS异常温升在线检测方法中最常用的是红外热像法，即红外测量外壳温度后经反演计算得到导体温度，但已有研究鲜少考虑日照等环境因素的影响。为了保障GIS安全可靠地运行，本研究针对日照下GIS母线的内部异常温升，提出了一种基于覆被隔热层的GIS内部异常温升在线检测方法。提出了基于覆被隔热层的GIS内部异常温升在线检测方法，在GIS外壳局部施加覆盖层，用以减少环境因素对温度检测的干扰，仿真分析了了覆盖层对提高“外壳-导体”温度对应关系的作用。正常通流裸露GIS在受到太阳辐射时温度整体升高，在不同太阳辐射下，外壳温度与导体温度并不一一对应，呈现分散性。隔热覆盖层增强了“外壳-导体”温度的对应性，降低了温度散点图的分散性，提高了用外壳温度评估导体温度的准确度。提出和建立了一个考虑太阳辐射的GIS母线覆被隔热层温升仿真模型。在GIS母线外壳外表面敷设了一层具有隔热效果的覆盖层，覆盖层传热系数低、表面发射率低，可以影响GIS在光照下的内部传热。分析了GIS发热中的内部热源和环境中的太阳辐射，并将三维涡流场仿真计算得到电磁损耗修正后作为内部热源，对太阳辐射的建模采用无和有两个极值模拟，传热模型考虑热传递、热对流和热辐射。并对建立的模型进行验证。研究了太阳辐射下GIS母线温升特性和施加覆盖层对太阳辐射的抑制作用以及对GIS与周围环境换热的抑制作用，建立了覆盖效果评定指标，获得了GIS长度为1m时的最优覆盖长度及角度，分析了GIS长度在3m内时上述最优覆盖方式的适用性。有覆盖时，覆盖层作用在两方面，一是改变GIS与周围环境的换热，使GIS温度升高；另一方面是抑制对太阳辐射的吸收，使GIS受外界环境的影响降低，温度分布接近无光照时。选定了覆盖长度、导体温升、对应效果及覆盖效果作为指标定性分析“外壳-导体”温度关系的对应性。研究了不同覆盖长度和覆盖角度的覆盖效果，最终选定最优覆盖方式。在此基础上，改变GIS长度，验证了上述最优覆盖方式仍可加强“外壳-导体”温度对应关系，提高温度检测准确度。
The reliability of the Gas Insulated Switchgear (GIS) bus is directly related to the temperature rise. The occurrence of heat faults seriously affected the safe and reliable operation of the power grid. In the GIS heat failure, a large proportion of the possession are caused by poor contact. At present, the most commonly used online detection method of GIS abnormal temperature rise is the infrared thermal portrait. Conductor temperature is obtained through infrared measurement and inversion calculation of shell temperature, but there are few studies that consider the influence of environmental factors such as sunlight. In order to ensure that GIS can operate safely and reliably, this paper proposes an online monitoring method for abnormal temperature rise inside GIS based on covered thermal insulation layer for the internal temperature rise of GIS bus bar under solar radiation.An online detection method of the GIS internal abnormal temperature rise based on the thermal insulation layer is proposed in this paper. The coverage layer is applied locally to the GIS shell to reduce the effects of environmental factors on temperature detection. The simulation analyzes the role of the coverage layer on improving the corresponding relationship between the "shell-conductor" temperature. Normally naked exposure GIS’s temperature is increased overall when radiated by the solar. Under different solar radiation, the shell temperature and the conductor temperature does not correspond one by one and show decentralization. The thermal insulation coverage layer enhances the correspondence of the "shell-conductor" temperature, reducing the decentralization of the temperature dispersion point diagram, and helping to improve the accuracy of the guidance temperature with the temperature of the shell.A simulation model of temperature rise of GIS bus covered insulation layer considering solar radiation is proposed and established. A layer of overlay with thermal insulation effect is laid on the outer surface of the GIS bus shell, and the heat transfer coefficient of the overlay layer is low and the surface emissivity is low, which can affect the internal heat transfer of GIS under light. The internal heat source and solar radiation in the environment of GIS heat are analyzed, and the electromagnetic loss is calculated through three-dimensional eddy current field simulation, after correcting its value, it serves as an internal heat source. Solar radiation is modeled using an infinity and two extrema simulations, and the heat transfer model considers heat transfer, heat convection, and thermal radiation. At last, the established model is verified.The temperature rise characteristics of GIS bus under solar radiation is established. Then, the inhibition effect of the application of the coverage layer on solar radiation and the inhibition effect of GIS and the heat exchange between GIS and the surrounding environment are studied. At last, the coverage layer effect evaluation index is established, and the optimal coverage length and angle of GIS length is obtained, and the applicability of the above optimal coverage method when GIS length is within 3m is analyzed. When the GIS is covered, the overlay acts in two aspects, one is to change the heat exchange between GIS and the surrounding environment, so that the GIS temperature increases. Another aspect is that it inhibits the absorption of solar radiation, so that GIS is affected by the external environment is reduced, and the temperature distribution is close to when there is no light. The coverage length, conductor temperature rise, corresponding effect and coverage effect are selected as indicators to qualitatively analyze the correspondence of the "shell-conductor" temperature relationship. The coverage effect of different coverage lengths and coverage angles are studied, and finally the optimal coverage method is selected. On this basis, changing the GIS length verifies that the above optimal coverage method can still strengthen the "shell-conductor" temperature correspondence and improve the temperature detection accuracy.
