35kV C-GIS环氧树脂外锥套管残余应力检测研究  

Study on Residual Stress Detection of External Conical Epoxy Bushing of 35 kV C⁃GIS

作　　者：贺春 何金 朱旭亮 陈荣[1,2] 李松原 刘松涛[3] 王雪生 郑渠岸 李进[4] HE Chun;HE Jin;ZHU Xuliang;CHEN Rong;LI Songyuan;LIU Songtao;WANG Xuesheng;ZHENG Qu􀆳an;LI Jin(State Grid Tianjin Electric Power Research Institute,Tianjin 300384,China;Tianjin Key Laboratory of Internet of Things in Electricity,Tianjin 300384,China;State Grid Tianjin Electric Power Company,Tianjin 300010,China;School of Electrical and Information Engineering,Tianjin University,Tianjin 300072,China)

机构地区：[1]国网天津市电力公司电力科学研究院,天津300384 [2]天津市电力物联网企业重点实验室,天津300384 [3]国网天津市电力公司,天津300010 [4]天津大学电气自动化与信息工程学院,天津300072

出　　处：《高压电器》2023年第4期38-43,共6页High Voltage Apparatus

基　　金：国网天津市电力公司科技项目(KJ22-1-26)。

摘　　要：环氧树脂浇注外锥套管在柜式气体绝缘开关设备中发挥载流导体和高压对地绝缘与支撑的关键作用,但工件内部残余应力与复杂的机械载荷叠加使外锥套管在运行工况下频繁发生开裂、击穿甚至解体等绝缘故障,严重威胁变配电系统安全稳定运行。文中以35 kV柜式开关设备外锥套管为研究对象,对比研究了超声法与钻孔法对其残余应力的检测效果,利用局部放电与抗弯试验验证了残余应力对工件运行可靠性的影响。主要结论如下:基于声弹性效应的残余应力检测方法发现环氧树脂外锥套管残余应力分布在-50~20 MPa。钻孔法检测结果表明外锥套管次表面残余应力分布为-7.5~7.6 MPa,与超声纵波法检测的残余应力检测位点一致,但是受钻孔深度影响,该方法具有一定限制。残余应力的存在使环氧树脂绝缘件机械重载运行后的局部放电量有所增加,使其机械强度大幅下降。因此需要严格控制环氧树脂绝缘件浇注工艺并开发残余应力检测方法。The epoxy resin casted external conical bushing plays a key role in acurrent⁃carrying conductor,high volt⁃age insulation to ground and support in cabinet⁃type gas⁃insulated switchgear(C⁃GIS),but the superposition of inter⁃nal residual stresses and complex mechanical loads induce such insulation fault as frequent crack,breakdown and even disintegration of the bushing under operating conditions,which seriously threatens safe and stable operation of substation and distribution systems.In this paper,the external conical bushing for 35 kV C⁃GIS is taken as the study object,the effect of ultrasonic method and drilling method on the detection of residual stresses is compared and stud⁃ied,and the effect of residual stresses on the operational reliability of the bushing is verified by using partial dis⁃charge and bending tests.The main conclusions ontained are as follows:the residual stress detection method based on the acoustoelastic effect finds that the residual stress distribution in the epoxy resin external conical bushing is⁃50~20 MPa.While,the detection results of the drilling method shows that the residual stress distribution in the exter⁃nal conical bushing subsurface is⁃7.5~7.6 MPa,which is consistent with the position of residual stress detected by the ultrasonic longitudinal wave method,but the method has some limitations due to the depth of drilling.The exis⁃tence of residual stresses increases the partial discharge of epoxy resin parts after mechanical load operation,which also causes a significant decrease in its mechanical strength.Therefore,it is necessary to strictly control the casting process of epoxy resin insulators and develop residual stress detection methods.

关 键 词：柜式气体绝缘开关设备 环氧树脂套管 残余应力 超声法 钻孔法 

分 类 号：TM643[电气工程—电力系统及自动化] TM216.5[一般工业技术—材料科学与工程]