JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF AU - Suda, K. AU - Hara, H. AU - Kako, E. AU - Kamigaito, O. AU - Miyamoto, A. AU - Nakai, H. AU - Ozeki, K. AU - Sakai, H. AU - Sakamoto, N. AU - Sennyu, K. AU - Umemori, K. AU - Yamada, K. AU - Yanagisawa, T. ED - Saito, Kenji ED - Xu, Ting ED - Sakamoto, Naruhiko ED - Lesage, Ana ED - Schaa, Volker R.W. TI - New Frequency-Tuning System and Digital LLRF for Stable and Reliable Operation of SRILAC J2 - Proc. of SRF2021, East Lansing, MI, USA, 28 June-02 July 2021 CY - East Lansing, MI, USA T2 - International Conference on RF Superconductivity T3 - 20 LA - english AB - The superconducting booster linac at RIKEN (SRILAC) has ten 73-MHz quarter-wavelength resonators (QWRs) that are contained in three cryomodules. The beam commissioning of SRILAC was successfully performed in January 2020. Frequency tuning during cold operation is performed by compressing the beam port of the cavity with stainless wires and decreasing the length of each beam gap, similar to the method adopted at ANL and FRIB. However, each tuner is driven by a motor connected to gears, instead of using gas pressure. Since the intervals of the QWRs are small due to the beam dynamics, a compact design for the tuner was adopted. Each cavity was tuned to the design frequency, which required frequency changes of 3 kHz to 7 kHz depending on the cavity. Although no piezoelectric actuator is mounted on the tuning system, phase noise caused by microphonics can be sufficiently reduced by a phase-locked loop using a newly developed digital LLRF. The details of the tuning system as well as the digital LLRF will be presented. PB - JACoW Publishing CP - Geneva, Switzerland SP - 666 EP - 670 KW - cavity KW - cryomodule KW - controls KW - SRF KW - operation DA - 2022/10 PY - 2022 SN - 2673-5504 SN - 978-3-95450-233-2 DO - doi:10.18429/JACoW-SRF2021-WEPTEV013 UR - https://jacow.org/srf2021/papers/weptev013.pdf ER -