This paper focus on the influence of oxygen on the partial discharge (PD) and decomposition characteristics of C 4 F 7 N/CO 2 /O 2 gas mixture as eco-friendly gas insulating medium. The PD characteristic parameters and phase resolved partial discharge (PRPD) patterns of C 4 F 7 N/CO 2 /O 2 gas mixture are, respectively, extracted and constructed. The influences of oxygen content and applied voltage on the PD and decomposition characteristics of C 4 F 7 N/CO 2 /O 2 gas mixture are investigated based on gas chromatography-mass spectrometry (GC-MS). We find that the addition of 2-4% O 2 to C 4 F 7 N/CO 2 gas mixture can significantly inhibit the negative half-cycle PDs and the generation of most by-products (CF 4 , C 2 F 6 , C 3 F 6 , CO, C 2 F 6 O 3 , CF 3 CN, C 2 F 5 CN, C 2 N 2 ). With the oxygen content higher than 6%, the accumulation discharge magnitude and discharge repetition rates of C 4 F 7 N/CO 2 /O 2 gas mixture increase sharply, accompanying the intensification of decomposition and deterioration of insulation strength. There is a positive correlation between the mean discharge magnitude and gas mixture decomposition intensity. To avoid the serious impact of PD fault on gas insulated equipment (GIE), the optimal oxygen addition in C 4 F 7 N/CO 2 /O 2 gas mixture should not exceed 6%.

中文翻译：

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O2对C4F7N/CO2/O2混合气体交流局部放电及分解行为的影响


本文重点研究了氧气对环保气体绝缘介质C 4 F 7 N/CO 2 /O 2 混合气体的局部放电(PD)和分解特性的影响。分别提取并构建了C 4 F 7 N/CO 2 /O 2 气体混合物的局部放电特征参数和相分辨局部放电(PRPD)模式。基于气相色谱-质谱联用技术(GC-MS)研究了氧含量和外加电压对C 4 F 7 N/CO 2 /O 2 混合气体的局部放电和分解特性的影响。我们发现，在C 4 F 7 N/CO 2 气体混合物中添加2-4% O 2 可以显着抑制负半周PD和大多数副产物（CF 4 、C 2 F 6 、C 3 F 6 、CO、C 2 F 6 O 3 、CF 3 CN、C 2 F 5 CN、C 2 N 2 )。当氧含量高于6%时，C 4 F 7 N/CO 2 /O 2 混合气体的累积放电强度和放电重复频率急剧增加，分解加剧，绝缘强度劣化。平均放电强度与气体混合物分解强度呈正相关。为避免局部放电故障对气体绝缘设备（GIE）造成严重影响，C 4 F 7 N/CO 2 /O 2 混合气体中的最佳氧添加量不应超过6%。