新型真空灭弧室1/2线圈纵磁结构设计与仿真

Design of new-type 1/2-turn AMF coil contact for vacuum interrupter and simulation

为了提高真空断路器的开断性能,本文设计一种新型1/2匝真空灭弧室线圈式纵向磁场触头结构,并对其纵向磁场分布特性进行分析。利用有限元方法建立三维结构模型并仿真,在电流分别处于峰值和电流过零时,得出静触头表面、开距中心平面和动触头表面上的纵向磁场分布以及纵向磁场的滞后时间;纵向磁场在触头表面与开距中间平面比较均匀,纵向磁场在静触头面的最大值为0.782 T,纵向磁场在动触头面的最大值为0.442 T,滞后时间为0.897 ms,导体电阻为28.25μΩ;新型结构新型触头结构具有较强的纵向磁场,电流过零后的剩余磁场小、滞后时间短,且温升较小。

To improve the opening contact of vacuum circuit breaker,a new-type 1/2-turn AMF（axial magnetic field） coil contact was designed for vacuum interrupters,with the characteristics of its AMF distribution discussed.By FEM,a relevant 3-D contact model was given for simulation.With the current at peak value and zero,the AMF distributions on stationary and moving contact surfaces and on the mid-gap plane between the two surfaces were all calculated,as well as the time lag of AMF.The results showed that the magnetic distribution is rather uniform on contact surface and mid-gap plane,and the maximum axial magnetic field acted on the stationary and moving contact is up to 0.782T and 0.442T,respectively,with a time lag about 0.879ms and conductor resistance 28.25μΩ.Simulation results revealed that the construction of the new-type contact can provide an axial high-intensity magnetic field whose residual field is small with short time lag after current zerocrossing and low temperature rise.