Search

This paper presents the electron beam misalignment study with respect to cathode position and cathode magnetic field of 42 GHz, 200 kW gyrotron. The performance of gyrotron is affected with the misalignment of cathode position. The simulation results confirm the tolerance of cathode misalignment with respect to the design parameters such as the transverse-to-axial velocity ratio, the maximum transverse velocity spread, etc. [ABSTRACT FROM AUTHOR]

In this paper, the evaluation of cathode-heater assembly of magnetron injection gun (MIG) for 42 GHz, 200 kW gyrotron is presented. The cathode-heater assembly is purchased from M/S SEMICON.The cathode-heater assembly is experimentally studied in three different conditions; in a belljar system, during vacuum processing of MIG and during MIG testing to ensure the required rise of cathode surface temperature for pre-set heater power. [ABSTRACT FROM AUTHOR]

Highlights: [•] The complete electrical design of 42GHz, 200kW gyrotron is presented. [•] Un-depressed collector and axial output system for RF power is selected. [•] Various commercially available design tools as well as in-house developed computer codes are used in the design process. [•] The experimental results of cold cavity analysis are also presented. [•] The design results show more than 200kW power with 40% interaction efficiency at 42GHz frequency. [Copyright &y& Elsevier]

Abstract: The electrical design of different components of 1MW, 170GHz gyrotron such as, magnetron injection gun, cylindrical interaction cavity and collector and RF window is presented in this article. Recently, a new project related to the development of 170GHz, 1MW gyrotron has been started for the Indian Tokamak. TE34,10 mode is selected as the operating mode after studied the problem of mode competition. The triode type geometry is selected for the design of magnetron injection gun (MIG) to achieve the required beam parameters. The maximum transverse velocity spread of 3.28% at the velocity ratio of 1.34 is obtained in simulations for a 40A, 80kV electron beam. The RF output power of more than 1MW with 36.5% interaction efficiency without depressed collector is predicted by simulation in single-mode operation at 170GHz frequency. The simulated single-stage depressed collector of the gyrotron predicted the overall device efficiencies>55%. Due to the very good thermal conductivity and very weak dependency of the dielectric parameters on temperature, PACVD diamond is selected for window design for the transmission of RF power. The in-house developed code MIGSYN and GCOMS are used for initial geometry design of MIG and mode selection respectively. Commercially available simulation tools MAGIC and ANSYS are used for beam–wave interaction and mechanical analysis respectively. [Copyright &y& Elsevier]

A triode magnetron injection gun (MIG) is designed for a 1-MW 170-GHz gyrotron, which will be used in an electron cyclotron resonance heating system for the International Thermonuclear Experimental Reactor. The initial design of MIG is performed by using the in-house code MIGSYN. For the electron-beam emission and propagation, the 2-D code EGUN is implemented. The transverse-to-axial velocity ratio \alpha is 1.37, and the transverse velocity spread less than 4% is realized. The results are also validated against two other 2-D and 3-D codes, i.e., TRAK and CST-Particle Studio, respectively, which are in close agreement. From the fabrication and operation point of view, the parametric analysis and misalignment study of electron beam are also performed. [ABSTRACT FROM PUBLISHER]

Abstract: In this paper, the three-dimensional simulation of triode-type magnetron injection gun (MIG) for 120GHz, 1MW gyrotron is presented. The operating voltages of the modulating anode and the accelerating anode are 57kV and 80kV respectively. The high order TE22,6 mode is selected as the operating mode and the electron beam is launched at the first radial maxima for the fundamental beam-mode operation. The initial design is obtained by using the in-house developed code MIGSYN. The numerical simulation is performed by using the commercially available code CST-Particle Studio (PS). The simulated results of MIG obtained by using CST-PS are validated with other simulation codes EGUN and TRAK, respectively. The results on the design output parameters obtained by using these three codes are found to be in close agreement. [Copyright &y& Elsevier]

A triode-type magnetron injection gun (MIG) for a 42 GHz, 200 kW gyrotron was designed by two commercial codes: EGUN and TRAK. An in-house code MIGANS was used as the post-processor of the EGUN. Some basic equations relevant to the problem available in literature were used while using the EGUN code for the purpose. The results on the design output parameters obtained by these two codes were found to be in close agreement. [ABSTRACT FROM AUTHOR]