Design and analysis of a tunable coupler for application to adjustable beam injectors

Yuan Yating; Zeng Bingqian; Hu Tongning; Li Xiaofei; Fan Kuanjun

doi:10.11884/HPLPB202234.210430

Volume 34 Issue 4

Mar. 2022

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Article Navigation > High Power Laser and Particle Beams > 2022 > 34(4): 044006

Yuan Yating, Zeng Bingqian, Hu Tongning, et al. Design and analysis of a tunable coupler for application to adjustable beam injectors[J]. High Power Laser and Particle Beams, 2022, 34: 044006. doi: 10.11884/HPLPB202234.210430

Citation:

Yuan Yating, Zeng Bingqian, Hu Tongning, et al. Design and analysis of a tunable coupler for application to adjustable beam injectors[J]. High Power Laser and Particle Beams, 2022, 34: 044006. doi: 10.11884/HPLPB202234.210430

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Design and analysis of a tunable coupler for application to adjustable beam injectors

doi: 10.11884/HPLPB202234.210430

1.
State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
2.
China Electric Power Research Institute Co Ltd, Wuhan 430074, China

Funds: National Natural Science Foundation of China (11905074)

More Information

Author Bio:
Yuan Yating, 361392645@qq.com
Corresponding author: Hu Tongning, tongninghu@hust.edu.cn
Received Date: 2021-10-13
Accepted Date: 2022-01-07
Rev Recd Date: 2022-01-23

Available Online: 2022-03-01

Publish Date: 2022-04-15

Abstract

Abstract

As a fundamental component of a linac-based beam injector, the rectangular-waveguide coupler is a conventional device for feeding high power, but it will induce field asymmetry and resonant-frequency shifting. Furthermore, it is also difficult to adjust the coupling factor for adjustable beam injectors. In this paper, an equivalent circuit model is established for the coupler with a tuning rod. Based on theoretical analysis, the optimal position for the rod is given. Besides, the frequency shifting is corrected by using another rod inserted to the cavity in the opposite direction. Sizes and adjustment ranges of both rods are given by three-dimensional electromagnetic simulation using CST MICROWAVE STUDIO. Jointly adjusted simulation results show that, critical-coupled states are achieved for different beam intensity while the resonant frequency remains stable, thus the risk of reflected power caused by coupler mismatching can be avoided, and the field asymmetry due to a small coupling hole can be reduced.
- coupling coefficient,
- resonance tuning,
- standing-wave cavity,
- RF accelerator

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References(15)

References

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