交流电晕放电下的SF_(6)气体发射光谱特性分析

Analysis on SF_(6) emission spectral characteristics under AC corona discharge

为探究SF_(6)发射光谱与异常放电缺陷的关系,本文模拟了一系列交流电晕放电实验,测量并分析了放电发展过程、不同气压、不同金属材料等条件下200~1 037 nm“紫外-可见光-近红外”波长范围内的发射光谱谱线与光谱强度。结果表明:电晕放电初期首先在420~510 nm出现了带状光谱,主要与SF_(6)分子内部能级跃迁以及SF_(6)电离生成的低氟硫化物有关;随着施加电压的增加,除420~510 nm谱段的光谱强度增大之外,309 nm附近也检测到了线状光谱信号,为微量水分电离产生的OH自由基所形成。继续增加施加电压至气体击穿时,200~1 037 nm全谱段均出现了以线状光谱为主的光谱信号,且相对光强高。这说明高放电能量下SF_(6)电离程度加深,产生了氟原子、氟离子、硫原子和硫离子等,进而释放出大量的光子。本文可为SF_(6)气体绝缘设备放电缺陷的光学识别提供参考。

In order to explore the relationship between the emission spectrum of SF_(6) and abnormal discharge defects,this paper carried out a series of AC corona discharge experiments,and measured the emission spectrum in the wavelength range of 200~1037 nm“ultraviolet-visible-near infrared”under the conditions of the discharge development process,different air pressures and different metal materials.The results show that a band-spectrum appears at 420~510 nm in the initial stage of corona discharge,which is mainly related to the energy level transition within the SF_(6) molecule and the low-fluorine sulfides generated by the ionization of SF_(6).The spectral intensity of 420~510 nm rises with increasing applied voltage,and the linear spectrum of the OH radical also appears near 309 nm generated by the ionization of trace water.When the applied voltage continued to increase until the gas breakdown,the spectrum spreads over the 200~1037 nm,and the linear spectrum is dominant.It is indicated that the ionization of SF_(6) is enhanced at high discharge energy,producing fluorine atoms,fluoride ions,sulfur atoms and sulfur ions,thereby greatly increasing the number of photons.This paper can provide a reference for the discharge pattern recognition of SF_(6) gas-insulated equipment based on emission spectroscopy.