Nuclear Techniques ›› 2018, Vol. 41 ›› Issue (6): 60202-060202.doi: 10.11889/j.0253-3219.2018.hjs.41.060202

• LOW ENERGY ACCELERATOR, RAY AND APPLICATIONS • Previous Articles     Next Articles

Design and implementation of frequency tracking and amplitude-phase feedback in RFQ low level control system

LI Mingda1,2, ZHAO Yubin1, ZHENG Xiang1, XIA Yangyang1,2, ZHANG Zhigang1, ZHAO Zhentang1   

  1. 1 Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jiading Campus, Shanghai 201800, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2018-03-22 Revised:2018-04-13 Online:2018-06-10 Published:2018-06-06

Abstract: [Background] The dynamic tuning of a radio frequency quadrupole (RFQ) is generally achieved via thermal regulation over the vanes and walls. However it takes tens of minutes to reach nominal power.[Purpose] The dynamic tracking of the RFQ's resonant frequency and the amplitude-phase feedback control will make it possible for the RFQ to be powered and form an acceleration field quickly, even though the cooling water of the RFQ does not reach thermal equilibrium.[Methods] An RFQ low-level control system implemented with direct digital synthesis (DDS) and phase-locked loop (PLL) technology was designed and tested at an experimental platform based on a simulation cavity.[Results] The test results show that this scheme can achieve the tracking of resonant frequency with ±0.5% amplitude stability and ±0.5° phase stability.[Conclusion] The performance of system meets expectation, and reaches acquired accuracy.

Key words: RFQ, Low Level Radio Frequency (LLRF), Field Programmable Gate Array (FPGA), DDS

CLC Number: 

  • TL503.6