SF_6中环氧绝缘子结构对其闪络特性的影响  

Influence of Epoxy Resin Insulator Structure on Its Flashover Characteristics in SF_6

作　　者：刘琳[1] 李晓昂[1] 赵军平[1] 张乔根[1] 马超群 梁成军 李志兵[2] LIU Lin1, LI Xiao＇ ang1, ZHAO Junping1, ZHANG Qiaogen1, MA Chaoqun1, LIANG Chengjun1, LI Zhibing2(1. State Key Laboratory of Electrical Insulation and Power Equipment, Xi＇ an Jiaotong University, Xi＇ an 710049, China; 2. China Electric Power Research Institute, Beijing 100192, Chin)

机构地区：[1]西安交通大学电力设备电气绝缘国家重点实验室,西安710049 [2]中国电力科学研究院,北京100192

出　　处：《高压电器》2018年第5期26-32,共7页High Voltage Apparatus

基　　金：国家电网公司科学技术项目(SGTYHT/15-JS-191)~~

摘　　要：绝缘子闪络是气体绝缘金属封闭开关的主要故障形式之一,提高绝缘子绝缘耐受水平可有效降低系统故障率。研究表明,洁净条件下的绝缘子闪络主要取决于绝缘子的沿面电场分布,而绝缘子及其屏蔽电极的形状均能够有效调节其沿面电场分布。文中设计并浇注了环氧支柱绝缘子样件,通过改变绝缘子形状、内屏蔽和外屏蔽电极的结构来调控其沿面电场分布;利用了负极性标准雷电波发生装置,实验研究了0.2 MPa SF_6环境下绝缘子的闪络特性;采用有限元分析方法,计算分析了绝缘子沿面电场的最大值。根据实验结果与仿真计算结果,分析得到绝缘子形状、内屏蔽电极形状、外屏蔽电极形状对绝缘子闪络特性的影响规律:凸面绝缘子的沿面电场具有最佳可调性;内屏蔽电极能够增大绝缘子的闪络电压也可以降低绝缘子的闪络电压;外屏蔽电极能够有效均匀电场但可能会缩短绝缘子沿面的有效爬电距离。Insulator flashover is one of the main failure modes of gas-insulated metal-enclosed switches. Increasing the flashover voltage of the insulator can effectively reduce the possibility of system failures. Previous studies have shown that insulator flashover under clean conditions mainly depends on the insulator surface electric field distribution,while the geometry of the insulator itself and its embedded and shielding electrodes can effectively adjust the electric field distribution along its surface. In this paper,epoxy post insulator samples were designed and casted. The distribution of electric field along the surface was regulated by changing the shape of the insulator,the embedded electrodes and the outer shielding electrodes. The negative standard lightning impulse generator was used to study the flashover characteristics of insulator samples immersed in 0.2 MPa SF_6. The finite element analysis method was used to determine the maximum value of the electric field along the insulator. According to the experimental and simulation results,the influence of insulator shape,embedded electrodes shape,and shielding electrodes shape on the insulator flashover characteristics is analyzed：the surface electric field of convex insulator has the best adjustability;the embedded electrodes can increase but can also reduce the flashover voltage of the insulator;the shielding electrodes can effectively uniform the electric field but may reduce the effective creepage distance along the insulator.

关 键 词：GIS 环氧绝缘子 屏蔽电极 闪络电压 SF6 有限元 爬电距离 

分 类 号：TM216[一般工业技术—材料科学与工程]