EMC protections for high voltage and high power on a wide facility — The mégajoule laser

This paper discusses the global EMC protections for the Megajoule Laser realized in ldquoCEA-DAM, CESTArdquo. The objectives are to understand the complex physic of nuclear fusion reaction and to validate the results of the Simulation program. The ultraviolet laser (350 nm) is designed to deliver 240 laser beams and 7.5 kJ each to transmit in a few nanoseconds 1.8 MJ on a 0.3 mg target filled with two isotopes of hydrogen, the deuterium and tritium, like the same fusion energy process in stars shine. The peak power will be about 550 TW. This experiment will allow the complex physic understanding of inertial confinement fusion and high energy density, the result takes an active part in the validation of Simulation program. In a first part we present the ground system protection for the Laser room included in the general ground building protection for a high level industrial EMC environment. In a second part we explain the harsh electromagnetic environment in the experiment room and the special EMC protections. This project requires a carefully controlled energy, a high precision timing and extreme precisely positioned targets near the centre of experiment chamber. The important challenge is to assure a good behaviour of troublemakers and sensible components in a same short time.