170 GHz回旋管大束流双阳极磁控注入电子枪的分析及设计

Analysis and design of double-anode magnetron injection gun for 170 GHz gyrotron

基于绝热压缩原理和强流电子光学理论,设计了一只170GHz回旋管双阳极磁控注入电子枪,经过理论分析及计算,采用仿真软件进行模拟和优化,最终得到的电子枪的电子注速度比为1.31,横向速度零散度为3.5%,纵向速度零散度为6.1%,束电流为51A。讨论了阴极磁场、控制阳极电压和第二阳极电压等因素对电子注性能的影响,发现电子注的速度比和速度零散度对这些影响因子的变化都非常敏感:随着阴极磁场的增大,电子注的速度比减小,纵向速度零散度先增大后减小,横向速度零散度先减小后增大;阳极角越接近阴极倾角,纵向速度零散度越小;阳极角向着减小阴阳极间距的方向变化时横向速度零散度变小;增大第一阳极电压可以增大电子注的速度比和电子注的速度零散度。在两阳极电压不变的情况下,增大阴阳极之间的距离会使电子注的速度零散度和电子注的速度比减小。

Based on adiabatic compression theory and electro-optical theory,a double-anode magnetron injection gun for 170 GHz gyrotron was designed.By theoretical analysis and calculations,using simulation software to simulate and optimizate the electron gun,and got the result that the velocity ratio of electron beam was 1.31,the transverse velocity spread was 3.5% and the axial velocity spread was 7.1%,the beam current was 51 A.The effects of the cathode magnetic field,the control voltage and the second anode voltage on the properties of electron beam were discussed and found that electron beam were very sensitive with these factors.When cathode magnetic field increased,the velocity ratio of electron beam decreased,the axial velocity spread increased first and then decreased,the transverse velocity spread decreased first and then increased.The increase of the first anode voltage could improve the velocity ratio and velocity spread of electron beam.The closer the anode angle and cathode angle,the smaller axial velocity spread.The transverse velocity spread became smaller while the anode angle changed toward the direction of reducing the distance between anode could cathode.When the two anode voltage did not change,the increase of the distance between cathode and anode could minish the velocity spread of electron beam but the velocity ratio decreased at the same time.