基于磁场与电弧互作的真空断路器触头结构设计

Design of Contact Structure of Vacuum Circuit Breaker Based on Interaction Between Magnetic Field and Arc

针对因真空断路器大电流故障开断过程中灭弧室断口场域磁感应强度弱,导致磁场对电弧等离子体有效控制力减弱的问题,将NSPSO多目标优化方法与磁场有限元分析相结合,以12 kV/1250 A/31.5 kA典型技术参数的中压真空断路器灭弧室纵磁触头系统为对象进行结构优化设计,以触头片开槽长度、斜槽深度、触头片开槽偏转角、触头杯座厚度为优化设计变量,以灭弧室断口中心截面纵磁最大值与磁场有效作用面积同时达到最大值为优化设计目标,求得Pareto前沿非支配优化解集,并筛选出磁场与电弧相互作用有效磁吹的最优化磁场结构。磁场优化设计结果表明,与初始结构相比,优化后触头结构极间中心面纵磁最大值升高了29.0%,纵磁磁场有效作用面积升高了5.7%。

In view of the problem that the weak effective control force of the magnetic field on the arc plasma during high current fault interruption of vacuum circuit breaker, the NSPSO multi-objective optimization is combined with the magnetic field finite element analysis, and the longitudinal magnetic contact system of the vacuum circuit breaker with the typical technical parameters of 12 kV/1 250 A/31.5 kA is used as the object for optimization design. The slotting length, the depth of the inclined slot, the slotting deflection angle of the contact and the thickness of the contact cup are taken as the optimized variables, and the maximum of longitudinal magnetic field strength of the central plane of the electrodes of interrupter and the maximum of effective area of the magnetic field are used as the optimization objective, the non-dominated optimal solution set of Pareto front and the optimal magnetic field structure of effective magnetic blowing is obtained. The magnetic field optimization results show that compared with the initial structure, the maximum longitudinal magnetic field strength of the center plane between the electrode of the optimized contact is increased by 29.0%,and the effective area of longitudinal magnetic field increased by 5.7%.