电工技术学报2025,Vol.40Issue(5):1601-1613,13.DOI:10.19595/j.cnki.1000-6753.tces.240191
直流GIS/GIL内微纳粉尘弥散浓度分布特性及对气隙击穿强度的影响
Characterization of Diffuse Concentration Distribution of Micron-Nano Dust in DC GIS/GIL and the Effect on Air Gap Breakdown Strength
摘要
Abstract
In the process of gas insulated switchger/gas insulated metal-enclosed transmission line(GIS/GIL)manufacturing,transportation,and servicing,the unavoidable generation and accumulation of metal dust at the micrometer level and below occur due to reasons such as switch contact collisions and mechanical vibrations.This minute-scale dust is challenging to detect,and its dispersion characteristics are not yet clear,potentially being the fundamental cause of air gap breakdown issues. The paper begins by investigating the light scattering characteristics of metal dust with particle sizes of 1 000 mesh,2 000 mesh,10 000 mesh,500 nm,and 50 nm.Based on this analysis,a micron-nano dust dispersion concentration detection system suitable for GIS/GIL is designed and built.The obtained dispersion concentration-voltage relationship functions for five particle sizes enable quantitative detection of micron-nano dust within coaxial cylindrical electrodes.This contributes theoretical guidance and technical insights for achieving detection of micron-nano dust dispersion concentration within GIS/GIL. Experimental results reveal a trend in the dispersion concentration of dust,showing an initial increase followed by a decrease with the rise in voltage level,indicating clear extremum and polarity effects.The dispersion motion of micron-nano dust between coaxial cylindrical electrodes is summarized into three processes:firstly,dust is lifted by forces towards the high-voltage electrode;upon contact with the high-voltage electrode,dust undergoes dispersion back-and-forth motion and some dust adheres to the high-voltage electrode due to various physical forces;after 10 minutes,dust dispersion motion stabilizes,resulting in slightly higher dust concentration compared to before pressurization.The probability of air gap breakdown increases significantly when the dust concentration in the light detection zone reaches about 80%of the peak concentration.The study also explores the impact of particle size,initial mass,material,initial position of dust,and electric field polarity on dust dispersion motion.Smaller particle size and larger initial mass lead to lower voltage levels at which peaks occur,resulting in higher peak concentration values and increased danger,the breakdown voltage can be reduced by up to 36.7%compared to the dust-free condition.Copper dust,with lower physicochemical activity,exhibits less dispersion motion at the same voltage level compared to aluminum dust,and its impact on the breakdown voltage of coaxial cylindrical electrodes is smaller.When the insulator and dust are at a certain distance,dust is likely to undergo dispersion motion and simultaneous adhesion along the insulator under the influence of the electric field,with less obvious extremum effects in dust dispersion motion. The study also analyzes the influence of researching the dispersion motion of micron-nano dust on the air gap insulation strength of coaxial cylindrical electrodes.Breakdown experiments are conducted with aluminum and copper dust of five different particle sizes,varying initial conditions such as particle size,initial mass,and material.When the dust concentration within the light detection area reaches 80%or less of the peak concentration,the probability of air gap breakdown significantly increases.Moreover,the decrease in breakdown voltage can reach a maximum of 36.7%when there is no dust.This provides a theoretical foundation and practical basis for further assessing the level of danger and achieving the detection of micron-nano dust dispersion concentration within GIS/GIL.关键词
GIS/GIL/微纳粉尘/光散射法/弥散浓度/气隙击穿Key words
GIS/GIL/micron-nano dust/light scattering method/dispersive concentration/air gap breakdown分类
信息技术与安全科学引用本文复制引用
王媛,杨睿成,苏宝亮,李玄,薛乃凡,李庆民..直流GIS/GIL内微纳粉尘弥散浓度分布特性及对气隙击穿强度的影响[J].电工技术学报,2025,40(5):1601-1613,13.基金项目
国家重点研发计划项目(2021YFB2601404)、国家自然科学基金(52127812)和中央高校基本科研业务费专项资金(2023JC005)资助. (2021YFB2601404)