Shi Chengyu, Gao Jingming, Li Song, Cui Yancheng, Yang Hanwu
College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China.
Rev Sci Instrum. 2019 Apr;90(4):044701. doi: 10.1063/1.5064451.
Ferromagnetic core based magnetic switches are widely used in various pulsed power facilities. The dynamic characteristics of high-power magnetic switches, which have important impacts on the pulse modulation process, are analyzed via an improved numerical model in this paper. The model is established by simultaneously solving the circuit equations and the magnetic field diffusion equations. An implicit finite difference method is used in solving the diffusion equations, which has no numerical convergence problems, and the Jiles-Atherton model is used to obtain an accurate hysteresis loop of the core. The improved model predicts the performance of the magnetic switch quite well. It is then used to analyze the detailed dynamic saturation process of a core, and the core's saturation time predicted by the model is consistent with the experimental data, the error being less than 5%. Furthermore, the interlamination electric field is calculated and analyzed, and it is predicted that breakdown is most likely to occur at the inner side of the core and at the edge of the lamination.
基于铁磁芯的磁开关广泛应用于各种脉冲功率设施中。本文通过改进的数值模型分析了大功率磁开关的动态特性，这些特性对脉冲调制过程有重要影响。该模型通过同时求解电路方程和磁场扩散方程建立。在求解扩散方程时采用了隐式有限差分法，该方法不存在数值收敛问题，并且使用Jiles-Atherton模型来获得准确的磁芯磁滞回线。改进后的模型能够很好地预测磁开关的性能。然后用它来分析磁芯的详细动态饱和过程，模型预测的磁芯饱和时间与实验数据一致，误差小于5%。此外，还计算并分析了层间电场，预测击穿最有可能发生在磁芯内侧和叠片边缘。
