C_(4)F_(7)N/CO_(2)混合气体与环网柜中固体材料的相容性试验

Experiments on Compatibility of C_(4)F_(7)N/CO_(2)Gas Mixture and Solid Materials in Ring Main Unit

全氟异丁腈(C_(4)F_(7)N)环保气体是目前国际主流推广的SF6替代气体,C_(4)F_(7)N/CO_(2)混合气体被广泛应用于环网柜等设备中。为了保障环网柜的长期稳定运行,需开展C_(4)F_(7)N/CO_(2)混合气体与环网柜典型固体材料相容性研究。该文提出了热加速和电热联合两种气固相容性试验方法,先对C_(4)F_(7)N/CO_(2)及分解气体与金属、塑料、橡胶和环氧玻纤等环网柜固体材料进行热加速试验,对比分析试验前后的气体成分及固体表面形貌、元素构成和光谱特性等关键性能,掌握了气固材料试样的相容性规律;在此基础上,采用环网柜整机带电相容性试验方法,施加运行电压和加热温度模拟现场工况,检测气体状态和设备绝缘性能的差异,结果表明C_(4)F_(7)N/CO_(2)混合气体与环网柜固体材料具有良好的相容性,满足长期可靠运行要求。该文提出的C_(4)F_(7)N混合气体与设备材料的气固相容性试验方法和规律等为环保气体电力设备的材料选型、设计研发提供了有益参考,具有重要的实用价值。

The eco-friendly gas of C_(4)F_(7)N is the main promotion of the SF6 alternative gas in the world at present.The C_(4)F_(7)N/CO_(2)gas mixture is widely applied in the ring main unit(RMU)and other equipment.In order to ensure the long-term stable operation of the RMU,it is necessary to investigate the compatibility of the C_(4)F_(7)N/CO_(2)gas mixture and the typical solid materials in the RMU.In this paper,two methods for the gas-solid compatibility testing,namely the thermal acceleration and the electro-thermal combination,are proposed.Firstly,the thermal acceleration test was carried out on the C_(4)F_(7)N/CO_(2)and its decomposition gases with the solid materials of the RMU such as metal,plastic,rubber and epoxy glass fiber.The key properties like the gas composition,the solid surface morphology,the element composition and the spectral characteristics before and after the test were compared and analyzed,obtaining the compatibility characteristics of the gas-solid material samples.Based on the sample test results,the electrified compatibility test of the whole RMU was conducted,applying the operation voltage and heating temperature to simulate the field condition.The changes of the gas compositions and the equipment insulation performance were detected.The results show that the C_(4)F_(7)N/CO_(2)gas mixture are well compatible with the solid materials of the RMU,meeting the requirements of the long-term reliable operation.The methods and principle of the gas-solid compatibility tests of the C_(4)F_(7)N gas mixture with the materials in the equipment provided in this paper is useful for the material selection,design and development of the eco-friendly gas-insulated power equipment,having the important practical value.