Electromagnetic Interference Consideration on Pulsed Kicker Magnet System

Electromagnetic interference (EMI) is a critical problem for pulsed magnet system, especially for those sophisticated measuring sensors used in synchrotron accelerator. The purpose of this paper is to estimate and reduce the conductive and radiated EMI from a kicker magnet and its power supply. A line impedance stabilization network system was implemented to measure the EMI spectrum of the kicker power supply. The EMI noise exceeded Federal Communications Commission (FCC) standards in some frequency ranges, especially during kicker firing. The conductive EMI level was reduced using various EMI filters. After the application of a double pi filter, the conducted EMI was lower than FCC class B. Moreover, we experimented with different thicknesses of aluminum plates to block a specific frequency of the radiated EM wave. Different widths of slits simulated the necessary openings on a kicker assembly. On the basis of the results, some parameters were obtained for the enclosure design of the kicker magnet. The experimental results provide valuable information for pulsed magnet design, and the parameters provide a believable guideline for the initial status of the Taiwan Photon Source kicker system.