Design and Evaluation of a New 2.2-MV Pulse Generator to Drive EMP Simulators While Reducing SF6 Emission

The electromagnetic pulse (EMP) generators in use at the CEA Gramat, France, deliver up to 2 MV with a 1-ns rise time. This high performance relies on sulfur hexafluoride (SF6) as the main insulator vector to withstand high-voltage stresses. To foresee further restrictions on greenhouse gases, CEA Gramat has started to look for a solution to improve the environmental aspect and ensure the long-term reliability of its EMP generators. This prospective study aims at defining innovative solutions while maintaining the same performance and canceling or at least minimizing the pollution from the use and release of SF6. The proposed design is a fast Marx generator coupled with a single pulse compression stage, called peaking stage. In comparison to the existing EMP generator, this scheme suppresses a compression stage and allows a large improvement in compactness, reducing at least by a factor of 6 the volume filled by insulating gas. The design of a 2.2-MV, 1-ns rise time and 60-ns width EMP generator is presented using circuit and 3-D electromagnetic (EM) simulations with static and transient solvers.