摘要
真空断路器分闸时产生的金属蒸汽在屏蔽罩内壁冷凝后形成金属毛刺缺陷,导致灭弧室内电场分布产生畸变,对真空灭弧室的可靠性产生不利影响。为此,以使用ZN28断路器的真空灭弧室为研究对象,建立对应的缺陷模型,研究在燃弧时因焦耳热产生的铜离子蒸汽的扩散规律,进而对存在金属毛刺缺陷时灭弧室电场的畸变情况进行分析。结果表明:在真空与电场的共同作用下,铜离子在屏蔽罩的落点主要集中在距中轴线25 mm以内的范围,概率分布曲线呈双峰形分布;当屏蔽罩内壁存在金属毛刺缺陷时,触头边缘的电场发生畸变,毛刺峰值越高,电场畸变越严重,当毛刺峰为0.25 mm时,真空灭弧室存在引起局部放电可能性。
The metal vapor generated during the opening of the vacuum breaker condenses on the inner wall of the shield cover and forms the metal burr defect,causing distortion of electric field in the arc extinguishing chamber and adversely affecting reliability of the vacuum arc extinguishing chamber.Taking ZN28 vacuum circuit breaker as the research object,this paper builds the corresponding geometric model to study the diffusion law of copper ion vapor produced by Joule heat during electric arc combustion and analyze distortion of electric field in the electric arc extinguishing chamber with metal burr.The results show that under the joint action of vacuum and electric field cover,the fall point of copper ion in the shield mainly concentrates within 25 mm from the central axis,the probability distribution curve is bimodal.In addition,when there is metal burr defect in the inner wall of the shield cover,the electric field at the edge of the contact deforms.The higher the peak value of burr,the more serious the distortion of electric field,and when the burr peak develops to 0.25 mm,there is a certain probability of partial discharge in the vacuum arc extinguishing chamber.
作者
刘源
陈玉材
LIU Yuan;CHEN Yucai(Huizhou Power Supply Bureau of Guangdong Power Grid Co.,Ltd.,Huizhou,Guangdong 516000,China;The 66469 Army of the Chinese People’s Liberation Army,Beijing 100042,China)
出处
《广东电力》
2020年第10期134-140,共7页
Guangdong Electric Power
关键词
屏蔽罩
金属毛刺
铜离子蒸汽
扩散规律
电场畸变
shield cover
metal burr
copper ion vapor
diffusion law
electric field distortion
