EBSM电子束扫描多极靴偏转线圈的多目标优化设计

Electron Beam Scanning Multipole Shoe Deflection Coil Multi-Objective Optimized Design of EBSM

针对电子束选区熔化增材制造的电子束偏转线圈偏转角度小、控制精度低等问题,设计了多极靴结构的扫描偏转线圈,选择极靴数量、磁芯类型作为试验变量进行正交仿真试验,并分析线圈内部磁感应强度的分布状态。以较高的中心磁感应强度、较低的磁场变化率作为线圈参数设计的优化目标。通过极差分析,确定两因素分别作用下每个指标的变化规律,并基于MOEA/D算法求解多目标优化问题。结果表明:极靴数量和磁芯类型均对线圈中心磁感应强度有显著影响,同时极靴数量对磁场均匀性具有积极影响;综合考量,十八极靴、无磁芯的线圈结构对于电子束大角度偏转和精确控制有显著优势。

To address the issue of small deflection angle and low control accuracy of the electron beam deflection coil in electron beam selection melting additive manufacturing,a scanning deflection coil with a multipole shoe structure was designed.The number of pole shoes and the type of core were selected as test variables to conduct orthogonal simulation tests,and the distribution state of magnetic induction strength inside the coil was analyzed.The optimization goal of the coil parameter udesign was to achieve a high central magnetic induction intensity and a low rate of magnetic field change.By performing extreme difference analysis,the variation law of each index under the action of two factors was determined,and the multi-objective optimization problem was solved based on the MOEA/D algorithm.The results demonstrate that the number of pole shoes and the core type significantly impact the magnetic induction strength at the center of the coil,and the number of pole shoes is the most significant influencing factor on magnetic field uniformity.In conclusion,the coil structure with 18 pole shoes and a coreless design has significant advantages for wide-angle deflection and precise control of the electron beam.