3D simulation of a realistic multistage depressed collector for high-power fusion gyrotrons
Proc. IEEE Int. Vacuum Electronics Conf. (IVEC), 2016, Apr, pp. 1–2
Multistage Depressed Collectors (MDCs) have been successfully applied in many kinds of vacuum tubes; however, there are only few discussions about applicable MDCs for high-power gyrotrons, regarding the hollow small-orbit electron beam and relatively strong stray magnetic field in the collector region. A novel concept has been recently proposed, where the electron beam is transformed into one or more sheet beams and sorted by the E×B drift. This contribution shows a 3D simulation result of a realistic seven-stage depressed collector model based on the above mentioned concept. With ordinary optimizations, a collector efficiency of 86 % has been achieved in this simulation.