摘要
空气中存在的水汽会使空气介电特性发生改变,严重影响输电线路外绝缘特性。为此通过理论及实验研究了湿度对流注放电的影响。理论方面通过Wieland近似法对湿空气的放电参数进行修正,对比分析了干洁空气与湿空气的放电参数,计算了不同湿度下针板气隙流注放电参数,提出了湿空气下流注起始、传播判据以及击穿电压计算方法。实验方面搭建流注放电室,进行棒板间隙流注放电实验,实验结果与理论计算结果相符。湿空气放电参数表明:低电场下(E/p<0.3V/(cm·Pa))湿度增大对电离系数影响不大,强电场情况下湿度对电离系数有着明显的促进作用;低电场时附着系数随湿度增大而增大,强电场时附着系数随湿度增大而减小;针板间隙流注计算结果表明湿度增大会使流注峰值电子密度、流注半径增大,流注传播速度加快;棒板击穿实验及击穿电压计算结果表明,当湿度较低时,湿度对击穿电压的影响不大,当相对湿度达到约94%时,湿度增大使得击穿电压明显提升。
The presence of water vapor in air will change the dielectric properties of the gas,which will seriously impair the external insulation properties of transmission lines.In this paper,the effect of humidity on streamer discharge is studied theoretically and experimentally.Theoretically,the discharge parameters of wet air are corrected by the Wieland approximation method,the discharge parameters of dry clean air and wet air are compared,the discharge parameters of needle plate air gap streamer discharge under different humidity are calculated,and the streamer initiation,propagation criteria and breakdown voltage calculation method under wet air are proposed.In terms of experiments,a streamer discharge chamber is built,and the bar-plate gap streamer discharge experiment is carried out.The experimental results are in good agreement with the theoretical calculation results.The wet air discharge parameters show that,under a low electric field(E/p<0.3 V/(cm·Pa)),the increase of humidity has a negligible effect on the ionization coefficient;under the condition of a strong electric field,humidity has a significant promoting effect on the ionization coefficient.The adhesion coefficient increases with the increase of humidity under a low electric field,and decreases with the increase of humidity under a strong electric field.The calculation results of streamer in pin-plate gap show that the increase of humidity will increase the peak electron density and radius of streamer,and accelerate the propagation speed of streamer.The bar-plate breakdown experiment and the calculation results of breakdown voltage show that,when the humidity is low,the humidity has a negligible effect on the breakdown voltage.When the relative humidity reaches about 94%,the increase of humidity will significantly increase the breakdown voltage.
作者
蒋兴良
吴建国
任晓东
胡建林
张志劲
JIANG Xingliang;WU Jianguo;REN Xiaodong;HU Jianling;ZHANG Zhijing(State Key Laboratory of Power Transmission Equipment&System Security and New Technology,Chongqing University,Chongqing 400044,China;Guangdong Power Grid Company Guangzhou Supply Bureau,Guangzhou 510620,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2023年第4期1743-1752,共10页
High Voltage Engineering
基金
国家自然科学基金(52077018)。
关键词
湿度
流注放电
数值计算
流注放电室
击穿实验
humidity
streamer discharge
numerical calculation
streamer discharge cell
breakdown experiment
