植物油纸绝缘的介电与热稳定性能

Dielectric properties and thermal stability of vegetable oil-paper insulation

植物绝缘油是一种新型高燃点、可再生、环保型的液体电介质,是矿物绝缘油的优良替代品.介绍植物绝缘油的实验室制备方法与植物绝缘油的基本电气及理化性能,分析植物油纸试样的工频击穿电压、介质损耗因数、介电常数等介电性能,并采用热重分析法研究油纸的热稳定性.试验与分析结果表明:植物油纸击穿电压高于矿物油纸击穿电压,植物油纸的介电常数和介质损耗因数与温度呈指数关系,其相对介电常数高于矿物油纸,而介质损耗因数与矿物油纸基本一致,植物油纸热稳定性比矿物油纸更高.

Insulating vegetable oils are renewable and environmental friendly dielectric liquids with high fire points.Such types of insulating oils are good substitutes of insulating mineral oils.This paper presents an approach to prepare the insulating vegetable oils in laboratory and their basic electrical,physical,and chemical properties.The insulating vegetable oil-paper insulation dielectric properties,including power-frequency breakdown voltage,dissipation factor,and relative dielectric permittivity,are investigated and analyzed.Its thermal stability is studied with thermogravimetry.Experiments and analysis results show that the oil-paper insulation breakdown voltage of vegetable oil is greater than that of the mineral oil.Their relative permittivity and dissipation factor increase exponentially with temperature.The oil-paper insulation relative permittivity of vegetable oil is greater than that of mineral oil,while the difference of their dissipation factors is small.Meanwhile,the oil-paper insulation thermal stability of vegetable oil is better than that of mineral oil.