| In the high energy electron accelerator device (HEEAD), the high energy electron acceleration system (HEEAS) plays a crucial part. The HEEAS consists of electron gun, accelerating tube, electron beam bunching system, scan system, and mainly functions to bunch the electron beam to the center along the axle of accelerating tube. The technical level and parameter of HEEAS determines the output energy, power, transfer efficiency and other key performance indicators of HEEAD. Although the development of electron beam bunching system related technology has been greatly pushed forward in China, there is still considerably distance from the developed countries. Therefore, the research on beam bunching system is of high practical value and significant importance to industries.This thesis researched and developed a new type of electron beam bunching system based on bunching coil of innovative structure, and economic field power supply of high stability and accuracy for beam bunching.First we designed and optimized the structure of bunching coil. In the HEEAD, the electron moves vertically under outfield effect, moves radially under the self-field effect of beam current, and moves angularly under axial field effect. Based on the characteristic of traveling wave electron linac and the particle dynamics analysis, to assure stable horizontal movement of electron in high-density electron beam, it is necessary to add external axially bunching magnetic field, which enables the envelope characteristic of electron beam current that is along the direction of accelerating tube meets the system requirements. The accelerating chain cavity usually has axial symmetric structure, and often accelerates electron by the axial component of TM wave magnetic field. The accelerating cavities are linearly coupled with periodic or quasiperiodic structure, and the field distribution follows Floque theory. To meets the periodic boundary condition, there should be infinite spatial harmonics in the accelerating system. The different spatial harmonics have the same work frequency and group velocity, but the phase velocity and wave number are different. In order to acquire continuing acceleration, the charged particles are required to meet certain synchronous acceleration conditions. For example, the traveling wave disk-loaded waveguide accelerating structure requires simultaneous phase velocity vp(z) and electron velocity ve(z). The acceleration tube we used are 10MeV/20KW with integral travelling wave impedance accelerating structure, including four beam bunching cavities and fifty even accelerating cavities. After computation, the horizontal beam bunching system of 10MeV/20KW traveling wave linac needs 15 solenoids (the 8th, 9th, 10th solenoids do not need field power supply, i.e. coiling is not necessary). Each solenoid is 9.2cm and the end structure is 4mm each, which contribute a total length as 10cm. The inside diameter is 152mm.Then, we designed a utility model of bunched power supply. To obtain good accuracy, stability and reliability of bunched power supply, it is necessary to give solutions to the negative impact caused by wave motion in electric network, load change and temperature change. Therefore, we used multiple technologies including micro processor, voltage regulator of controlled silicon phase modulation, deep degenerative stabilizer, and developed an intelligent bunched power supply. Through preliminary test on sample machine, the key technical indicators like output current stability, current ripple factor, voltage regulation rate, load regulation rate, and power supply transfer efficiency all meet practical requirements and the work done in the thesis takes a great step in the research of new type HEEAD.
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