BEPC II magnet power supply control system

Two rings will be constructed in the current tunnel to increase the luminosity of BEPC II. There will be approximately 460 magnet power supplies in the rings and transport line. Most magnet power supplies require 1 x 10-4 control precision and stability. Only the dipole power supply requires 5 x 10-5 control precision and stability. Using a PSC/PSI for the control of a high precision prototype PS, it has been proven that the PSI can meet the requirement of 5 x 10-5 precision and stability. For easy integration and maintenance, the authors decided to use the same hardware and software for the control of all PS in the rings and transport line. So, the control of all power supplies will be based on the PSC/PSI modules and the EPICS toolkits. This paper describes the application of the PSC/PSI for the BEPC II power supply control. The status of application software development and power supply control is discussed. (authors)