THE USE OF SWITCH-MODE POWER CONVERTERS FOR THE LEP MAIN RING POWER CONVERTER SYSTEM

By the beginning of the 1980's it was evident that dc power converters working with high internal switching frequencies could offer substantial advanta-ges in the accelerator environment. Reduced volume, high efficiency and excellent dynamic performance were among the attractions. But just how much power could be obtained and at what price was not clear. The search for suitable topologies which could not only cover the sub-kilowatt range but also the higher power levels was thus launched. This paper describes the work that has been carried out on switch-mode tech-niques at CERN and their application to a majority of power converters for LEP. The range of Switch-Mode Power Converters for LEP will vary from 340 W up to 40 kW and from 2.5 A to 2'000 A dc output. The paper will show how they have become an important part of the power converter system of LEP, allowing substantial savings in building size and cooling while offering much improved dynamic qualities. introduction--.-_-The LEP main ring magnet syste,n requires about 7 6:: in(,i>;iduui ~owcr converters, Iqhich amcnqst other-things 'III,<: tf 051s to grow witk the macnine: By th