两种不同结构纵一横复合触头磁场计算及电弧实验研究

Study on Magnetic Field Calculation and Arc Experiment for AMF-TMF Composite Contacts with Two Different Structures

磁场调控技术是提高真空断路器开断能力的重要方式,通过纵向磁场(AMF)可以使电弧保持扩散态,而横向磁场(TMF)可以驱动电弧在电极间高速旋转以降低触头的烧蚀。近年来,一种新型的复合磁场(TMF-AMF)触头得到了广泛关注,在电流较小时电弧保持扩散态,在电流大到一定程度出现电弧集聚时可以使电弧旋转。文中设计了两种不同结构的复合磁场触头,首先分析了两种触头的磁场,并进行了结构上的优化,然后进行了定开距条件下的触发电弧实验,比较了两种触头结构的电弧特性,研究结果表明:结构1的复合触头能充分利用整个触头盘,而结构2的复合触头将电弧束缚在内触头盘附近,不能充分利用外触头盘,更容易出现金属熔化。

Magnetic field control technology is an important way to improve the interruption capability of vacuum circuit breaker.The axial magnetic field(AMF)can keep the arc diffuse,while,the transverse magnetic field(TMF)can drive the arc to rotate at high speed between electrodes with purpose of reducing contacts ablation.In recent years,a new type of composite magnetic field(TMF-AMF)contacts has attracted widespread attention,which can,in case of small current,keep the arc diffuse and,in case of sufficient high current and appearance of constricted arc,drive the arc to rotate.In this paper,the composite magnetic field contacts with two different structures are designed.First,the magnetic field of the two kinds of contacts is analyzed and the optimization in structure is performed.Then,the triggered arc experiments under fixed clearance are carried out and the arc characteristics of the two structures are com-pared.The study results show that the composite contact of the first structure can make full use of the whole contact plate,while the composite contact of the second structure can keep the arc near the inner contact plate,cannot make full use of the outer contact plate and be more prone to fusion of metal.