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Choi, J.

Paper Title Page
MPPP003 FALSE BPM READINGS AFFECTING ORBIT FEEDBACK 847
 
  • H.-S. Kang, J. Choi, M.-H. Chun, K.M. Ha, J.Y. Huang, Y.-C. Kim, E.-H. Lee, T.-Y. Lee, W.W. Lee, J.-H. Suh
    PAL, Pohang, Kyungbuk
 
  Funding: Ministry of Science and Technology, Korea.

A slow global orbit feedback (SOFB) is routinely operating in the usual user service operation at PLS. The orbit feedback uses 22 correctors in each plane which have 20-bit capability for the vertical plane and 16-bit capability for the horizontal plane, and the feedback speed is 4 seconds. The orbit stability in RMS was maintained below 1 mm in both planes for one hour and 3 mm for a 12-hour operation. The BPM chamber movement due to the change of synchrotron radiation heat load mainly limits the SOFB performance. The intensity dependence of BPM electronics is well compensated by a look-up table of BPM.

 
WPAE061 LC Filter for High Accuracy and Stability Digital MPS at PLS 3550
 
  • S.-C. Kim, J. Choi, K.M. Ha, J.Y. Huang
    PAL, Pohang, Kyungbuk
 
  Funding: Work supported by the Ministry of Science and Technology, Korea.

High accuracy and stability digital power supply for magnet is developed at PLS. This power supply has three sections. The first section is digital controller including DSP&FPGA and precision ADC, the second consists of IGBT driver and four quad IGBT switch, and the third is LC output section. AC input voltage of power supply is 3-phase 21V, output current is 0 ~ 150 A dc. Switching frequency of IGBT is 25 kHz. The output current of power supply has very high accuracy of 100 mA step resolution at full range and the stability of ± 1.5 ppm for short term and ± 5 ppm for long term. This paper describes characteristics of filter and output current performance improvement after LC output filter at four quad digital power supplies.

 
WPAT014 Sequence Control System of 1-MW CW Klystron for the PEFP 1401
 
  • B.R. Park, J. Choi, M.-H. Chun, Y.J. Han, M.H. Jeong, S.-C. Kim, J.S. Yang, I.H. Yu
    PAL, Pohang, Kyungbuk
 
  Funding: Work support by the PEFP(Proton Engineering Frontier Project), Korea.

Sequence control system of 1-MW CW klystron for the PEFP (Proton Engineering Frontier Project) has been developed in order to drive the 1-MW klystron amplifier. The system is able to control several power supplies and many environment conditions. The hardware of sequence control and the interlock system are based on the Allen-Bradley's SLC500 Program Logic Controller (PLC). Also the system can be controlled by a touch screen at local mode or Ethernet network with high level HMI at remote mode.

 
RPAE046 Operational Status at the PLS: Recent Improvements and Changes 2923
 
  • E.S. Park, J. Choi, H.-S. Kang, M. Kim, E.-H. Lee, T.-Y. Lee
    PAL, Pohang, Kyungbuk
 
  PLS has been operated 10 years since 1994. A few improvements has been made to stabilize the reference orbit drifts caused by insertion devices and other sources: The control system has been upgraded to 20 bit capability from 12 bit. The slow global orbit feedback is employed routinely in the user run times. These improvements and the operational status changes will be presented in this report.  
FPAT050 Improvement RF Control System for the 20 Mev Proton Linac of PEFP 3100
 
  • J.C. Yoon, J. Choi, H.-S. Kang, J.-W. Lee
    PAL, Pohang, Kyungbuk
 
  Funding: EPICS, Control, LLRF.

This paper presents the RF control system for Korea Multi-purpose Accelerator Complex (KOMAC). KAERI (Korea Atomic Energy Research Institute) has been performing the project named KOMAC. As the 3nd phase of the project, 20MeV proton accelerating structure is under development. The new design is based on the use of VME based Multi-function modules connected to the specific low level RF Controllers(LLRF) via distributed I/O modules and Serial communication modules. The control system was based on EPICS (Experimental Physics and Industrial Control System) from the end of 2004. Installation and commissioning of the RF module is scheduled on 2005. Control system to integrated the RF System to the KOMAC control system is implemented. Hardware, software and various applications are upgrade to support the operation of RF Control system. In this paper, We describe control structure and scheme of the current RF Control System and upgraded one.