Abstract：This paper proposed an optimized magnetic diffusion model to analyze magnetic flux density, current density, Joule heat, electromagnetic force and current skin depth in different time and position of an electromagnetic launcher. The model concerned on the difference caused by the contact state, so that the multi-field distribution under the conditions of irregular armature shape, driving current waveform can be obtained. The result shows that when the interference is 1mm, the actual contact area is in the middle of the theoretical contact area, and the current concentrates at the rear end of the actual contact area and then moves ahead. It is found that the difference in electrical conductivity of the actual contact area would not affect the current distribution after the other four typical contact states were analyzed. Due to the skin effect, the skin depth close to the armature is shallow, and the ramp current has more obvious skin effect than the step current. The results deduced by this model are consistent with the theoretical formula. This study can provide an approach to observe transition, skin effect and armature structure optimization, laying a foundation for 3D field calculation.
张嘉炜, 鲁军勇, 谭赛, 张永胜, 李白. 考虑初始接触压力的滑动电接触界面磁扩散模型[J]. 电工技术学报, 2022, 37(2): 488-495.
Zhang Jiawei, Lu Junyong, Tan Sai, Zhang Yongsheng, Li Bai. A Magnetic Diffusion Model of Electromagnetic Launcher Considering Initial Contact Pressure. Transactions of China Electrotechnical Society, 2022, 37(2): 488-495.
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