Design and testing of a high voltage coil for the kicker magnets of CERN's Large Hadron Collider

The Large Hadron Collider (LHC), the world¹s largest proton and lead-ion accelerator, is currently under construction at CERN, Geneva, Switzerland. To extract the particle beams at the end of a physics run and in emergency situations 2 beam abort systems, built of 14 fast high-power kicker magnets each, are required. These magnets will operate at 35 kV and 30 kA with a pulse length of 90 ms and a rise time of 3 ms. A prototype magnet with a single turn high voltage coil has been built and tested. The magnet closely surrounds a ceramic vacuum tube. In order to insert this beam pipe into the magnet, the coil and the magnet have to be built in two halves which can easily be separated. The paper describes the design principles of the high voltage coil, the different options for the coil insulation material, as well as details concerning the adopted manufacturing process. The paper also describes the extensive loss-factor measurements which have been carried out as part of the acceptance tests. Finally it reports on endurance tests of the coil when mounted inside the magnet yoke and working in pulsed mode.