W波段回旋行波管新型曲线阴极磁控注入电子枪优化设计

Optimal design of a novel magnetron injection gun with curved emitter for a W-band gyrotron traveling wave tube

设计了采用新型曲线阴极结构的W波段双阳极磁控注入电子枪,手动优化得到的电子注参数在速度比1.1时,纵向速度零散为1.84%.为了克服手动优化方法的繁琐和低效,引入了数值计算方法的优化策略,编制了基于MATLAB语言的遗传算法和模拟退火算法的优化程序,并结合二维电子光学软件EGUN对该W波段曲线阴极结构电子枪进行优化,优化得到的电子枪在保证电子注速度比1.1的情况下,纵向速度零散分别达到了0.81%和1.05%.与手动优化方法相比,数值优化方法不需要设计者干预优化过程,具有自动高效的特点,且优化结果更好.

The design of a novel magnetron injection gun with curved emitter for a W-band gyrotron traveling wave tube has been presented. An axial velocity spread of 1.84% with beam velocity of 1.1 is obtained by manual optimization. To overcome the complexity and inefficiency of manual optimization, numerical optimizing methods are employed. Optimizing codes based on genetic algorithm （GA） and simulated annealing algorithm （SAA） are completed by using the MATLAB program language. 2- D electro-optic code EGUN is employed to calculate and optimize the electron trajectories and beam parameters. The achieved velocity spreads optimized by GA and SAA are 0.81% and 1.05%, respectively, when velocity ratio is kept at 1.1. Compared with manual optimization, the numerical optimizing methods do not need the designers to get involved in the optimizing process. Besides, the numerical optimizing methods feature automation and high-efficiency, and often, the optimizing results are better.