Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Improvement of transmission-line-based fault locating for typical traveling-wave accelerator with constant-gradient structures

  • T.N. Hu (State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology) ;
  • Y.F. Zeng (State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology) ;
  • K. Peng (China Academy of Space Technology (Xi' an)) ;
  • H. Hu (State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology) ;
  • H.M. Wang (State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology) ;
  • K.F. Liu (State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology)
  • Received : 2023.07.26
  • Accepted : 2024.01.06
  • Published : 2024.06.25
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Abstract

Since RF breakdown is one of the primary limitations to improving the performances of RF accelerators, extensive efforts have been dedicated to locating the breakdowns. However, most existing methods rely on specialized techniques, resulting in high financial burdens. Although the method based on transient response of transmission line (TL) is suitable for facilities with sporadic recoverable breakdowns, practical operations are susceptible to notable errors. This study revisits the fundamental theories of lossless TL and investigates the wave process to understand the characteristics of the reversed pulse induced by the breakdowns. By utilizing steadystate response of the TL and employing phasor method, we derive analytical formulas to determine the exact location of breakdowns within the faulty cell for constant-gradient TW accelerator. Furthermore, the derived formulas demonstrate their independence from RF phase, thereby distinguishing them from traditional phasebased methods. Additionally, experimental validations are conducted at the HUST injector, and the results confirm the consistency of the analysis. Thus, the proposed method represents a promising improvement over the TL-based approaches and serves as a valuable complement to current techniques. Importantly, this method demonstrates particular advantages for constructed TW accelerators seeking to achieve a balance among high performance, low costs, and compact layouts.

Keywords

Acknowledgement

This work was supported by National Natural Science Foundation of China (NSFC) under Project Numbers 11905074, and the Interdisciplinary program of Wuhan National High Magnetic Field Center (Grant No. WHMFC202142).

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