2/3匝线圈式纵磁触头大开距真空断路器分闸速度设计  

Design of Opening Velocities for Large-Gap Vacuum Circuit Breakers with 2/3 Coil-Type Axial Magnetic Field Contacts

作　　者：马飞越 姚晓飞[2] 刘志远[2] 孙尚鹏 白涛 Ma Feiyue;Yao Xiaofei;Liu Zhiyuan;Sun Shangpeng;Bai Tao(State Grid Ningxia Electric Power Corporation Research Institute,Yinchuan 750002,China;School of Electrical Engineering Xi′an Jiaotong University,Xi′an 710049,China;Shizuishan Power Supply Company State Grid Ningxia Electric Power Co.Ltd,Shizuishan 750029,China)

机构地区：[1]国网宁夏电力有限公司电力科学研究院,银川750002 [2]西安交通大学电气工程学院,西安710049 [3]国网宁夏电力有限公司石嘴山供电公司,石嘴山750029

出　　处：《电工技术学报》2024年第13期4139-4152,共14页Transactions of China Electrotechnical Society

基　　金：宁夏回族自治区重点研发计划项目(2022BDE93011);国网宁夏电力有限公司科技项目(5229DK22000B)资助。

摘　　要：合理设计纵磁触头真空断路器的分闸速度特性,可有效避免大电流开断过程中真空电弧阳极斑点的形成或缩短阳极斑点持续时间,显著提升断路器短路电流开断性能。然而,现阶段仍然缺乏线圈式纵磁触头真空断路器全行程分闸速度特性的量化设计方法。该文试验研究了电弧电流、分闸速度对2/3匝线圈式纵磁触头大电流真空电弧阳极放电模式演变的影响规律,获得了不同分闸速度下线圈式纵磁触头阳极放电模式图,据此提出线圈式纵磁触头分闸速度的量化设计方法:初始分闸速度v1应不小于其从强电弧模式演变为扩散态电弧模式的临界触头开距峰值所对应的分闸速度;平均分闸速度v2应不大于大开距活跃阳极放电模式形成的临界触头开距峰值所对应的分闸速度;同时,对比实际开断过程中触头间隙磁感应强度与阳极放电模式演变的临界纵向磁感应强度,可校验上述分闸速度特性设计的合理性,并能预测该纵磁触头以任一分闸速度开断任一短路电流时的阳极放电模式演变特性。应用上述方法,该文确定了126 kV单断口真空断路器的分闸速度特性设计值为v1=3.5 m/s、v2=3.0 m/s,并通过型式试验验证了断路器在上述分闸速度特性下的短路电流开断性能。The development of vacuum circuit breakers(VCBs)towards transmission voltage is an effective alternative of SF6 CBs on background of carbon dioxide emission and carbon neutrality nowadays.In the VCBs,the axial magnetic field(AMF)contacts have been widely mounted tends to promote the breaking capability of circuit breakers.The vacuum arc plasma can be constrained by the axial magnetic field lines to counteract the pinch force of conducting current,which always concentrate the arc plasma at local anode surface to generate an anode spot in high current interruption process.In this case,a rational design of opening velocities for the VCBs with coil-type AMF contacts could effectively regulate the flux density of the axial magnetic field imposed on the electrode space.However,there is still a lack of quantitative design method for a full stroke opening velocities of the VCB with coil-type AMF contacts.This paper experimentally investigates the influence of arcing current and opening velocities on evolution of vacuum arc anode discharging modes.Couples of coil-type AMF contacts,tending to be applied in a 126 kV single-break vacuum circuit breaker,were mounted in a demountable vacuum chamber to investigate the influence of opening velocities on transitions of vacuum arc anode discharging mode.A high charge coupled device(CCD)was used to photograph these transitions.Two kinds of opening velocities,v1 and v2,were used to define an opening travel-curve:v1 is an initial opening velocity,which defines as an average velocity over 1/3 contact stroke,d,of 60 mm;while,v2 is an average velocity over 2d/3.In the experiment,v1 varied from 1.8 m/s to 2.4 m/s and 2.7 m/s,respectively.Correspondingly,v2 varied from 2.4 m/s to 2.7 m/s and 3.0 m/s.The arcing current was set to rise from 4 kA to 40 kA,stepped by 4 kA.Test result shows that v1 has significant impact on the transition of intense arc mode into diffuse arc mode in the first arcing current loop,while v2 significantly influences the formation of both footpoint mode and anode s

关 键 词：纵向磁场 大开距 真空断路器 阳极放电模式 分闸速度 

分 类 号：TM561.2[电气工程—电器]