阴极帽结构L波段相对论磁控管的效率提升

Efficiency enhancement of L-band relativistic magnetron with endcaps

提出了一种具有阴极帽结构的L波段相对论磁控管的设计方案,并给出了数值模拟结果。在相对论磁控管中引入阴极帽是为了降低轴向泄露电流并提高功率转换效率。三维粒子模拟用于研究引入阴极帽后产生的影响。结果显示,当在束波互作用区域的上游和下游同时添加阴极帽,并且将阴极延伸出阳极块结构,直至衍射输出结构时,轴向泄露电流不仅会从1 kA降至72 A,且功率转换效率会有明显提高。虽然如此,阴极帽的引入除了以上优点外,同样会带来微波反射。因此,阴极帽的半径和位置对于效率有至关重要的影响,它们之间存在一个最优数值来保证效率最高。当电压为563 kV,磁场为0.34 T时,轴向衍射输出结构L波段相对论磁控管输出微波功率为2.13 GW,频率为1.59 GHz,相应的功率转换效率为75.5%。

An L-band relativistic magnetron with cathode endcaps is presented and investigated numerically.Cathode endcaps are introduced in the relativistic magnetron to decrease the axial leakage current and enhance the power efficiency.Three-dimensional particle-in-cell simulations are carried out to investigate the effects of the cathode endcaps.The simulation results indicate that when adding cathode endcaps at both upstream and downstream of the interaction space and extending cathode beyond the anode block into the diffraction output(DO),electron leakage current is reduced from above 1 kA to 72 A and the power efficiency increases obviously.The endcaps can not only decrease the leakage current but also bring microwave reflection.Thus,the radius and the location of the endcaps have significant impact on power efficiency,and they have optimum values to make the efficiency highest.Typical optimized simulation results are as follows:working at an applied voltage of 563 kV and a magnetic field of 0.34 T,the relativistic magnetron with diffraction output(MDO)radiates microwave of 2.13 GW at 1.59 GHz,and the corresponding power conversion efficiency is 75.5%.