Development of multistage energy recovery system for gyrotrons

Abstract

A four-stage depressed collector based on spatial separation of electrons with different energies in the crossed electric and magnetic fields was developed for the experimental SPbPU gyrotron. Modeling of the system of electron energy recovery and analysis of the distributions of electric and magnetic fields in the gyrotron collector region were performed. As a result of the theoretical estimations and the trajectory analysis of the helical electron beam, it is shown that the developed system provides recovery of the residual electron energy necessary to achieve the total efficiency of the gyrotron exceeding 70 %.