CERN Accelerating science

Article
Title	LC Filter for High Accuracy and Stability Digital MPS at PLS
Author(s)	Kim Sung Chul ; Choi Jinh Yuk ; Man Ha Ki ; Yun Huang Jung
Affiliation	(PAL, Pohang)
Publication	2005
In:	21st IEEE Particle Accelerator Conference, Knoxville, TN, USA, 16 - 20 May 2005, pp.3550
Subject category	Accelerators and Storage Rings
Abstract	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.