Development of a computer-controlled magnet power supply for KEK PS beam lines

Abstract

This paper reports the present status of the development of computer-controlled magnet power supplies (12-phase thyristor converter) for the KEK 12 GeV proton-synchrotron beam lines. We have been developing a power supply in which an 8-bit microcomputer is embedded and which can be interfaced to a host computer. This power supply has the following advantages: (1) the load on the host computer is reduced; (2) maintenance of the power supplies becomes easier; and (3) the current control is carried out by a microcomputer program instead of conventional regulator circuits. At present a current stability of 2×10 −4 has been achieved within 10 ms for a 1% change of line voltage. 2.5% of CPU time is used for this current control.