AMF与TMF高频磁场特性仿真对比分析

Comparative Analysis on Simulation of AMF and TMF High Frequency Magnetic Field Characteristics

真空灭弧室的灭弧性能与真空灭弧室触头的磁场特性密切相关,其中纵向磁场(AMF)灭弧技术与横向磁场(TMF)灭弧技术应用最为普遍。基于人工零点的高压直流真空断路器,引入高频震荡电流帮助开断,为了分析真空断路器开断高频电流情况下的磁场特性,文中建立了两种类型的触头结构进行有限元仿真,对比分析真空灭弧室磁场特性以及触头片涡流情况。结果表明:在高频电流开断情况下,横磁结构触头与纵磁结构触头相比有更好的磁场特性分布;触头片涡流是影响纵磁结构触头磁场特性恶劣的关键因素,而对横磁触头间隙磁场特性几乎没有影响。

The arc interruption performance of vacuum interrupter is closely related to the magnetic field characteristics of the vacuum interrupter contacts.Both axial magnetic field(AMF)and transverse magnetic field(TMF)arc interruption technologies are the most commonly used technologies.HVDC vacuum circuit breaker based on artificial zero⁃point introduces high⁃frequency oscillating current to help interruption.In order to analyze the magnetic field characteristics of the vacuum circuit breaker under high⁃frequency current,two types of contact structures are set up for finite element simulation.The magnetic field characteristics of the vacuum interrupter and the eddy current of the contact piece are compared and analyzed.The result shows that,in case of high frequency current interruption,the contact of transverse magnetic structure has better magnetic field characteristic distribution than that of longitudinal magnetic structure.The eddy current of the contact piece is the key factor causing deterioration of magnetic characteristic of contact with axial magnetic structure and,however,has almost no influence on the magnetic field characteristics of the transverse magnetic contact gap.