摘要
直流电压作用时,气–固绝缘系统电场由容性分布逐渐向阻性分布过渡,该过程伴随着电荷的积聚与消散,可能会引起闪络电压降低,但其变化规律仍不够明确。综合考虑了固体侧体电荷电导、气体侧正负离子电导以及界面电荷电导,建立了气–固绝缘系统电荷积聚模型,通过支柱绝缘子模型表面电位分布的测量与仿真,实现了电荷积聚模型的验证。利用该模型计算分析了直流电压下盆式绝缘子在电场过渡过程中的电荷积聚规律,研究了体积电导率对电荷积聚的影响规律。结果表明:电场过渡过程中,盆体凸面主要积聚同极性电荷,其高压侧附近场强降低约9.4%,低压侧附近场强增大约23.5%;盆体凹面大部分区域主要积聚异极性电荷,场强增大约5.5%;当体积电导率在10-14~10-17 S/m之间时,盆体凸面积聚同极性电荷,盆体凹面主要积聚异极性电荷,随着体积电导率进一步降低,盆体表面电荷积聚机制逐渐转为由气体侧电导主导,电场畸变进一步加剧。该研究可为直流盆式绝缘子的绝缘设计提供计算分析依据。
The electric field of gas-solid insulation system will gradually transit from capacitive distribution to resistive distribution under DC voltage.This process is accompanied by the accumulation and dissipation of charges,which may cause the decrease of flashover voltage,but the regularity is still not clear enough.Consequently,the volume charge conductance in solid,ions conductance in gas and interface charge conductance were taken into consideration,so that a charge accumulation model for gas-solid insulation system was established.And the correctness of the model was verified by measuring and simulating the surface potential distribution of a post insulator sample.Moreover,the charge accumulation on the surface of basin insulator during the electric field transition process under DC voltage was computed and analyzed.The influence of volume conductivity on charge accumulation characteristics was investigated.The results show that,in the process of electric field transition,the convex surface of the basin mainly accumulates homopolar charges.The electric field intensity near the high-voltage side decreases by 9.4%and the electric field intensity near the low-voltage side increases by 23.5%.The heteropolar charges mainly accumulate in most areas of concave surface and the electric field intensity increases by 5.5%.When the volume conductivity is between 10-14 S/m and 10-17 S/m,the convex surface of the basin insulator accumulates homopolar charges,while the concave surface mainly accumulates heteropolar charges.With the further decrease of volume conductivity,the mechanism of charge accumulation on the surface of basin insulator gradually turns to be dominated by gas-side conductivity.And the electric field distortion on the surface of basin insulator is further aggravated.The research in this paper can provide a calculation and analysis reference for the insulation design of DC basin insulators.
作者
杨为
朱太云
田宇
杨熙
朱胜龙
叶剑涛
YANG Wei;ZHU Taiyun;TIAN Yu;YANG Xi;ZHU Shenglong;YE Jiantao(State Grid Anhui Electric Power Company Limited Research Institute,Hefei 230022,China;State Grid Anhui Electric Power Company Limited,Hefei 230022,China;School of Electrical Engineering and Automation,Hefei University of Technology,Hefei 230009,China;State Key Laboratory of Electrical Insulation and Power Equipment,Xi’an Jiaotong University,Xi’an 710049,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2020年第6期1978-1985,共8页
High Voltage Engineering
基金
国网安徽省电力有限公司电力科学研究院科技项目(SGAHDK00SPJ1900205)。
关键词
气–固界面
电场过渡
电荷积聚
体积电导
盆式绝缘子
gas-solid interface
electric field transition
charge accumulation
volume conductivity
basin insulator
