C_(4)F_(7)N/CO_(2)混合气体工频击穿和分解特性  

Power Frequency Breakdown and Decomposition Characteristics of C_(4)F_(7)N/CO_(2)Gas Mixtures

作　　者：陈翔 陈炯 CHEN Xiang;CHEN Jiong(School of Electrical Engineering,Shanghai University of Electric Power,Shanghai 200090,China)

机构地区：[1]上海电力大学电气工程学院,上海200090

出　　处：《上海电力大学学报》2025年第2期182-189,共8页Journal of Shanghai University of Electric Power

摘　　要：全氟异丁腈(C_(4)F_(7)N)混合气体具有优良的绝缘性和环保性,被视为SF_(6)的潜在替代气体。为此,构建了工频击穿试验平台,研究了在不同气压、电场不均匀度和组分比例下C_(4)F_(7)N/CO_(2)混合气体的击穿和分解特性,并分析了它们的协同效应。研究结果表明:均匀电场中,C_(4)F_(7)N/CO_(2)混合气体的工频击穿电压随气压升高呈现出线性上升趋势;在稍不均匀电场且气压较低时,该混合气体与纯SF_(6)气体的击穿特性相似,但气压继续升高时,纯SF_(6)气体的工频击穿电压上升速率减缓,最终低于混合气体;在极不均匀电场下,该混合气体的工频击穿电压随气压升高呈饱和增长的趋势,其协同系数在0.25~0.45范围内,表现出明显的协同效应。对不同气压下的分解过程分析可知:C_(4)F_(7)N/CO_(2)混合气体主要生成的自由基包括CF、CF_(2)、CF_(3)、CN、C_(3)F_(7)、F、N和O,同时还会通过复合反应生成CF_(4)、C_(2)F_(6)、CO等较小的分子产物,C_(4)F_(7)N分子数量呈现下降趋势,且气压越高,下降速率越快,CO_(2)分解虽加剧,但不会完全分解。The perfluoroisobutyronitrile C_(4)F_(7)N mixed gas exhibits excellent insulating and environmental properties,making it a potential substitute for SF_(6).To this end,a high-frequency breakdown test platform is constructed to study the breakdown and decomposition characteristics of C_(4)F_(7)N/CO_(2)gas mixtures under different pressures,electric field inhomogeneity,and component ratios,and to analyze their synergistic effects.The research results show that in a uniform electric field,the high-frequency breakdown voltage of the C_(4)F_(7)N/CO_(2)gas mixtures shows a linear increase with increasing pressure.In a slightly non-uniform electric field and at lower pressures,the breakdown characteristics of this mixed gas are similar to those of pure SF_(6)gas.However,as the pressure continues to increase,the rate of increase in the breakdown voltage of pure SF_(6)slows down,eventually falling below that of the mixed gas.Under extremely non-uniform electric fields,the high-frequency breakdown voltage tends to saturate with increasing pressure;the synergistic coefficient of the C_(4)F_(7)N/CO_(2)mixed gas is between 0.25 and 0.45,showing a significant synergistic effect.Analysis of the decomposition process at different pressures reveals that the main free radicals produced include CF,CF_(2),CF_(3),CN,C_(3)F_(7),F,N,and O,and smaller molecular products such as CF_(4),C_(2)F_(6),and CO are also formed through recombination reactions.The number of C_(4)F_(7)N molecules decreases,and the rate of decrease is faster at higher pressures,while the decomposition of CO_(2)intensifies without complete decomposition.

关 键 词：C_(4)F_(7)N/CO_(2)混合气体 击穿特性 分解特性 电场不均匀度 协同效应 分解产物 

分 类 号：TM852[电气工程—高电压与绝缘技术]