C4F7N-CO2-O2三元环保混合气体电子群参数研究OA

Sulfur hexafluoride(SF6)has become the mainstream insulating medium for medium and high-voltage electrical equipment due to its excellent insulating and arc-extinguishing properties,yet it is in urgent need of replacement because of its strong greenhouse effect characteristics.Heptafluoro-isobutyronitrile(C4F7N),as a highly potential new eco-friendly insulating gas,has become a research hotspot by virtue of its superior electrical performance and low environmental harm.However,existing studies mostly focus on its binary mixture systems with a single buffer gas,and the research on electron swarm parameters of the C4F7N-CO2-O2 ternary mixture gas remains a blank which restricts the plasma simulation and engineering application of this system.Therefore,based on the test method combining the high-precision pulsed Townsend(PT)experimental platform with physical model analysis,this paper carries out experimental verification on the measurement of electron swarm parameters for C4 F7 N-CO2-O2 ternary mixture gases with different ratios under the pressure of 200 Pa.The effective ionization rate coefficients,electron drift velocities and density-normalized longitudinal diffusion coefficients of the mixture gases are obtained,the critical reduced breakdown field strengths of the mixture gases with different ratios are determined and the synergistic effects between C4F7N and CO2-O2 buffer gases are analyzed,providing essential data for C4F7N's engineering applications.