Abstract

Three-dimensional simulation of the motion of a multibeam electron flow in high power multibeam klystrons for high values of the efficiency (70\(\%\) and higher) is necessary. The value of the efficiency calculated earlier in terms of the one-dimensional and two-dimensional models only for one partial beam is higher than that experimentally measured, usually by 10–15\(\%\) of the absolute value. An increase in the number of partial beams and a transversely developed configuration of ring cavities (an ‘‘oversized’’ cavity), as a rule, lead to an increase in the inhomogeneity of the microwave field distribution along the drift tubes of the ring cavity and generate a phase difference of microwave fields (phase incursions).

It is shown here that energy extraction even from identical electron bunches of a multibeam flow depends on the location of the partial drift tube relative to the energy output. The use of the BAC method of electron bunching can increase the efficiency of klystrons. The results of 3D simulation of the interaction of a multibeam electron flow in the output ring cavity of a BAC-klystron with an output pulse power of 6 MW have made it possible to estimate quantitatively the influence of the phase incursions of the waves. It has been shown that the phase difference of the microwave fields in the output cavity significantly reduces the interaction efficiency and, consequently, the efficiency of multibeam klystrons. Thus, the phase delay of the waves excited in different drifts tubes of the gap of an ‘‘oversized’’ output ring cavity is one of the physical reasons for limitation of the efficiency of multibeam klystrons.

中文翻译：

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大功率多束速调管效率的物理局限性

摘要

为了获得高效率值（70 \（\％\）和更高），必须对高功率多束速调管中多束电子流的运动进行三维仿真。仅针对一个部分光束的一维和二维模型，较早计算出的效率值要高于实验测量的效率，通常为绝对值的10–15 \（\％\）。通常，分束数的增加和环形腔（“超大尺寸”腔）的横向展开配置通常会导致沿环形腔的漂移管的微波场分布的不均匀性增加并产生微波场的相位差（相位侵入）。

在此表明，即使从多束流的相同电子束中提取能量也取决于部分漂移管相对于能量输出的位置。BAC电子束聚方法的使用可以提高速调管的效率。对BAC速调管的输出环腔中的多束电子流与6 MW的输出脉冲功率进行交互作用的3D模拟结果，使得可以定量估计波的相位侵入的影响。已经表明，输出腔中微波场的相位差显着降低了相互作用效率，因此降低了多束速调管的效率。从而，