Compact output filter for switching frequency elimination at the PLC Linac new magnet power supply

Abstract

Pohang Accelerator Laboratory Linac magnet power supply (MPS) has been upgraded for the stable beam injection and 4 th generation light source research, in 2006. MPSs are developed as compact configuration by using four quadrant switching scheme with power MOSFET. In case of 10V, +/-10A bipolar output operation, main circuit is operated as one or three quadrant, and in case of 50V, 50A unipolar output operation, main circuit is operated as parallel one quadrant. Switching frequency of MOSFET switch is above than 40 kHz. MPS consists of main power board, control power board, regulator board and CPU board. The size of each board has 100mm width and 250mm depth. Main power board made of fourquadrant MOSFET switch, driver and output filter. Output filter must be perfectly eliminating switch frequency and have compact size. In this paper, we report on development and characteristics of compact output filter of the new MPS for PAL linac.