Study On Electron Gun And Collector Of 300kW Gyrotron Electron Optical System

Due to the structure and working mechanism of traditional microwave devices,the research on the millimeter wave band is limited,and the gyrotron based on the electron cyclotron maser theory fills a very important blank of the electromagnetic wave source spectrum.Compared with other traditional microwave devices,high-power gyrotron is a reliable high-power microwave source.It has far higher operating frequency and output power than traditional microwave devices,It has strong application prospects in millimeter wave and submillimeter wave science.It is widely concerned by more and more scientists.Electron optical system is an important part of the gyrotron.This article is to simulate and study the electron gun and collector in the gyrotron electron optical system.We design the 300kW gyrotron electron optical system,and the electron gun in the gyrotron electron optical system and collector for simulation studies.The main work of this paper is as follows:1.The theory of electron optics is expounded.From the perspective of electrostatic field and static magnetic field,reasoning analysis is based on Maxwell's equations.Then an analysis of the adiabatic compression of an important characteristic of the transition zone in the electron gun is presented.The analysis shows the trajectory of the electrons in the electron gun,which provides a theoretical basis for how to optimize the electronic injection.2.According to the design requirements of the 300kW gyrotron studied in this paper,the design of the magnetron injection type electron gun was simulated by PIC,and the various factors affecting the performance of the electron injection are analyzed in detail.Finally,an electronic bet was designed to power the 300 kW gyrotron,which has a velocity ratio of 1.2 and a lateral velocity dispersion of 3.5%.3.For the collection of polar defocusing analysis,the collector is defocused optimized,and the PIC simulation software is used to simulate the collector.By adding a compensation coil,the collector magnetic field is changed,so that the electron injection can be hit on the collector wall in advance.Increases the collection area of the collector and reduces the collection power per unit area of the collector.It is found that the falling point range of the electron beam on the collector is 302mm,.The power density is 442.9w/cm~2,which meets the design requirements of the 300kW gyro collector.