电场对复合绝缘子积污特性影响的探究  

Effect of the Electric Field on the Contamination Accumulation Characteristic of the Insulators

作　　者：王晶[1] 陈林华[1] 刘宇[1] 梁曦东[1] 

机构地区：[1]清华大学电机工程与应用电子技术系电力系统及发电设备控制和仿真国家重点实验室,北京100084

出　　处：《高电压技术》2011年第3期585-593,共9页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2011CB209406);国家重点实验室自主课题~~

摘　　要：绝缘子的积污规律很大程度上取决于绝缘子周围尘粒的运动特性,通过试验和数值计算两种途径探究了各种因素对尘粒运动的影响。通过同轴电极模型试验探究了电场对尘粒运动的影响,建立了简化的二维轴对称数值计算模型,模拟了尘粒在极化力、电场力、稳态曳力和重力同时作用下的运动轨迹,仿真结果与试验结果比较符合,最后,计算了真实特高压直流复合绝缘子周围的电场和电位分布。研究结果表明:极化力非常小,对尘粒运动不会产生影响,但可使尘粒在绝缘子表面粘附地更加牢固;电场力可使荷电尘粒在电场线的方向上发生明显偏转,而绝缘子伞裙之间的电场方向基本与伞裙表面垂直,因此,电场力可促进荷电尘粒在直流绝缘子表面的沉积;在风速较大时,稳态曳力对尘粒运动起主导作用,尘粒随风而动。从电场对尘粒运动所产生的影响出发能更好地解释不同类型的绝缘子在不同运行条件下的积污规律。Contamination accumulation characteristic of the insulators depends on the kinetic characteristic of the particles moving around the insulators to a great degree.We researched the effect of different factors on the dust particles＇ motion by means of experiments and numerical calculation.The effect of electric field was researched by coaxial electrode model experiments.A simplified 2D axial symmetric calculation model was built to simulate the dust particles＇ trajectories under the composite effect of the polarization force,the electric field force,the steady-state drag force and the gravitational force.The simulation resulted in good coincidence with the experimental phenomenon.In the end,the distribution of the electric field and the electric potential around an actual EHVDC insulator was calculated.The results are as bellow： The polarization force is very weak and can not influence the dust particles＇ motion but make the particles＇ adhesion to the insulator＇s surface firmer.The charged dust particles deflect along the electric field line driven by the electric field force,and the direction of the electric field between the insulator＇s sheds is almost perpendicular to the sheds＇ surface,so the electric field force can promote the precipitation of the dust particles on the dc insulators.When wind is strong,the steady-state drag force dominates and the particles move with the wind.The contamination accumulation characteristic of different insulators under different operating conditions can be better explained on the basis of the effect of the electric field on the dust particles＇ motion.

关 键 词：复合绝缘子 尘粒 运动特性 积污特性 电场力 电晕 

分 类 号：TM216[一般工业技术—材料科学与工程]