电子直线加速器电子枪栅控脉冲板的短脉冲特性研究

用等效电路法探讨了电子枪栅控脉冲板的短脉冲输出波形及幅度，并给出与关晶体管数量间的关系。依此研制成功的脉冲板满足了中国科学技术大学国家同步辐射实验室２００ＭｅＶ电子直线加速器的要求，该设备几年来一直稳定工作。     

NFZ-10工业辐照电子直线加速器束流控制方法

在ＮＦＺ－１０工业辐照电子直线加速器上，分析了以输出束流来负反馈控制轰击型二极电子枪灯丝电压进而稳定输出束流的方法及存在的缺点。提出了新的控制轰击高压的方法，在此加速器上得到了高稳定性和高精度的输出束流。     

用于电子静电加速器的多阴极电子枪

为了延长电子静电加速器的运行周期,1973年起我们在电子静电加速器上改用多阴极电子枪。该电子枪由上海先锋电机厂制造,在一个枪体内装有4根灯丝。一根工作,另外三根备用。当工作的灯丝损坏时可方便地通过控制转换,使第二根继续工作,这就大大节省了为更换灯丝打开钢桶而花费的很多时间。本文简要叙述多阴极电子枪的结构以及在使用中的一些改进。     

12千伏-100毫安高压稳定电源

本文介绍的是用于强流短脉冲电子直线加速器电子枪的高压稳定电源,是一台中型电源设备,输出电压从2千伏至12千伏,电流从零至100毫安连续可调。在需要高压大电流输出的场合,本电源也是通用的高压电源。一、引言在核物理实验中,高压电源是一种基本的电子学仪器。根据实验的要求,通常使用的高压电源输出电压为几千伏,输出电流为几毫安。本电源是根据实验工作的需要设计而成,它具有输出电压高、电流大、调节范围宽等特点。     

多能量双束线电子直线加速器研制

<正>研制了可输出电子能量为7.5、10、12 MeV的电子直线加速器,7.5 MeV电子束打靶产生的X射线用于食品辐照技术研究,10 MeV电子束用于科研教学和中试生产研究,12 MeV电子束主要应用于半导体材料辐照改性研究,多能量双束线电子直线加速器主体结构如图1所示。该电子直线加速器布置采用上下两层结构,电子枪、加速管、速调管、微波系统和脉冲变压器等置于第2层     

一种微波栅控直流电子枪初步物理设计

红外波段自由电子激光的小信号增益大小以及饱和功率对束流的能散非常敏感。为满足远红外自由电子激光对能散的要求,在合肥光源栅控直流高压电子枪的基础上,模拟了一种热阴极微波栅控直流高压电子枪。微波栅控直流高压电子枪采用微波栅控的方法,控制和压缩阴极引出电子束团的长度。再通过直流高压对电子加速后,在电子枪的出口可以得到量级为几十皮秒的束团。本文使用SUPERFISH、POISSON分别进行栅控微波场与高压电场优化计算,PARMELA(Phase And Radial Motion in Electron Linear Accelerators)进行束流跟踪与分析,得到一组能满足红外自由电子激光需求的电子枪参数。     

等离子喷涂硼化镧阴极电子枪

一、引言现代大型医用电子直线加速器电子枪的设计有如下特点: 1.要求电子枪束流在大范围内连续可调。对于一个二极型电子枪系统,枪必须工作在温度限制区域内,故阴极发射的稳定性十分重要。2.行波电子直线加速器通常采用可拆性结构,这就要求阴极必须有较好的抗中毒特性。     

C波段9 MeV驻波电子直线加速管设计

介绍了C波段驻波电子直线加速管的研制情况.该加速管采用2.5 MW脉冲磁控管为微波功率源,脉冲宽度4μs,重复频率250 MHz.可提供能量为6 MeV和9 MeV两档能量的电子束,工作频率为5712 MHz,管长约620 mm.通过调节加速管的入口功率、电子枪的注入电压实现加速管的输出能量两挡调变.     

50 kV全数字化电子枪高压电源设计

本文介绍了一种基于DSP的全数字化电子枪高压电源,该电源的特点是采用全数字化反馈电路、通过PID算法实现闭环控制。采用频率较高的谐振逆变电路,减小了谐振元件、变压器的体积。电源因采用电流耦合型分布式高压变压器及整流电路,提高了效率、减少了分布参数及可使高压整流电路工作在无油的环境中。该电源已成功用于辐照加速器电子枪栅控高压电源系统中。     

宽范围高精度电子枪控制系统的研制

本文针对"1.2 MeV/10 mA高频高压型电子加速器及束线"项目中钨丝阴极热发射电子枪的控制需求,在了解了系统组成和工作原理的基础上,采用三极式平板热阴极发射电子枪,阴极材料使用钨丝,灯丝加热电源由发电机供电,引出电压从加速管电极分压获得。通过设计一种基于可编程逻辑控制器(Programmable Logic Controller,PLC)的控制系统,实现了电子枪引出1μA～50 mA 4个数量级范围的直流电子束。该控制系统采用PLC作为设备控制器,LabVIEW软件作为用户界面,通过通信协议(Object Linking and Embedding for Process Control,OPC)接口实现控制软件与设备控制器的通讯。实验测试表明,系统具有可靠稳定、灵活高效等特点。     

多模式下电子枪脉冲发生器

介绍了合肥同步辐射光源的栅控电子枪触发系统的改进,使其在运行时无需更换脉冲形成线路板,而实现了微秒和毫微秒级脉冲两种工作模式的切换运行。此脉冲形成线路板已投入试运行,并在储存环中得到多束团和单束团的储存束流。     

钪酸盐阴极电子枪双短脉冲发射实验研究

本工作研究在ns量级双脉冲高压下钪酸盐阴极电子枪电流发射。实验中采用Blumlein线形成ns量级脉冲高压作为电子枪馈入高压,脉冲宽度约为80ns,双脉冲间隔约为300ns。实验结果表明:在消除了空间高频干扰后,法拉第筒测量到的电子枪发射电流脉冲形状与馈入的ns量级双脉冲高压形状非常吻合。由此验证了钪酸盐阴极电子枪对ns级脉冲高压发射响应能力能满足双短脉冲高压工作状态要求,可以作为ns量级多脉冲电子束注入器。     

The Use of an Electron Microchannel as a Self-Extracting and Focusing Plasma Cathode Electron Gun

A new and simple type of electron gun is presented.Unlike conventional electron guns,which require a heated filament or extractor,accelerator and focusing electrodes,this gun uses the collimated electron microchannels of an inertial electrostatic confinement(IEC) discharge to achieve the same outcome.A cylindrical cathode is placed coaxially within a cylindrical anode to create the discharge.Collimated beams of electrons and fast neutrals emerge along the axis of the cylindrical cathode.This geometry isolates one of the microchannels that emerge in a negatively biased IEC grid.The internal operating pressure range of the gun is 35-190 m Torr.A small aperture separates the gun from the main vacuum chamber in order to achieve a pressure differential.The chamber was operated at pressures of 4-12 m Torr.The measured current produced by the gun was 0.1-3 m A(0.2-14 m A corrected measurement) for discharge currents of 1-45 m A and discharge voltages of 0.5-12 k V.The collimated electron beam emerges from the aperture into the vacuum chamber.The performance of the gun is unaffected by the pressure differential between the vacuum chamber and the gun.This allows the aperture to be removed and the chamber pressure to be equal to the gun pressure if required.     

兰州高能电子成像实验平台电子束团长度测量研究

为提高高能电子成像的时间和空间分辨率,实验需低能散、低发射度、短脉冲的高品质束流。本文利用相干渡越辐射能谱分析法测量基于热阴极微波电子枪的高能电子成像用直线加速器的电子束团长度。通过用迈克尔逊干涉仪测量太赫兹辐射能谱,利用自相关曲线拟合法得到电子束团长度。实验结果表明,当束流宏脉冲峰值强度约为24 mA,即电荷量约为15 pC时,电子束团均方根长度约为0723 5 ps。另外,用Kramers Kronig(K K)相位分析法可重建一种可能的电子束团纵向分布。电子束团长度测量的研究可优化束流品质,对后续高能电子成像实验有重要的参考意义。     

Non-equilibrium ignition criterion for magnetized deuterium–tritium fuel

A compact 15.0-MeV, 1.5-kW electron linear accelerator(LINAC) was successfully constructed to provide an electron beam for the first photoneutron source at the Shanghai Institute of Applied Physics, Shanghai,China. This LINAC consists of five main parts: a thermal cathode grid-controlled electron gun, a pre-buncher, a variable-phase-velocity buncher, a light-speed accelerating structure, and a high-power transportation beamline. A digital feedforward radio frequency compensator is adopted to reduce the energy spread caused by the transient beam loading effect. Furthermore, a real-time electron gun emission feedback algorithm is used to keep the beam stable. After months of efforts, all the beam parameters successfully met the requirements of the facility. In this paper, the beam commissioning process and performance of the LINAC are presented.     

350keV电子高压加速器研制

加速器辐照装置用于辐照生产医用输液塑料袋原膜材。所研制的350keV电子高压加速器具有以下特点：在静电加速器中采用高压倍压电源代替输电带，此新型结构加速器可输出低能大功率电子束，且体积小、自屏蔽，适于在线辐照加工；一般高压倍压电源采用50Hz供电，而在此装置中由14kHz中频电源供电，高压电源体积小。加速器空载高压达370kV，电子束350keV/20mA，扫描宽度70cm，辐照剂量不均匀性好于7%。该加速器辐照装置已投入运行，并已生产出合格医用输液袋膜材投放市场，产品填补了国内医用输液袋膜材市场的空白。     

Design of Electron Gun for 1.5 MW, 140 GHz Gyrotron

This paper presents the design of the triode type electron gun for a 140 GHz, 1.5 MW gyrotron with the transverse to the axial velocity ratio of the beam 1.4 and the transverse velocity spread 1.28%. The operating mode of the gyrotron is TE_24,8 and it is operated in the fundamental harmonic. The analytic trade-off equations for the electron gun design have been used to estimate the initial gun parameters. The electron trajectory tracing program has been used to optimize the electron gun design. The parametric dependences of modulating anode voltage, beam voltage and cathode magnetic field on the beam quality has also been studied.     

Electron cyclotron heating power supplies on DIII-D

The electron cyclotron heating system on DIII-D has been supporting experiments with six gyrotrons. The gyrotrons are connected to three power supplies: two have single modulators, each energizing two gyrotrons, while the third has three modulators that can energize three gyrotrons asynchronously. However, only two gyrotrons can be run synchronously due to the limitation of the high voltage dc power supply providing the input voltage to the modulators. These two configurations mimic proposed architectures of power systems for multiple gyrotron systems and demonstrate their advantages or disadvantages, which will be discussed in more detail. A fourth power system is being built as part of an upgrade to eight gyrotrons. The two future gyrotrons will have depressed collectors. A 1.2 MW gyrotron will be delivered in mid-2011 and the design of a 1.5 MW gyrotron has been initiated. This fourth power supply will have two modulators to independently energize the cathode of each gyrotron. Commercially available high voltage amplifiers will provide the body voltage. It will also have a solid-state crowbar instead of an ignitron crowbar. This power supply is described in more detail, as well as the testing performed on the solid-state crowbar to prove its performance.     

微型X射线管灯丝电源的研制

根据微型X射线管的特点,设计了基于推挽电路和闭环反馈电路的灯丝驱动电源。采用了UCC3808脉宽调制(Pulse Width Modulation,PWM)控制芯片产生两路相位相反的PWM信号,并经由UCC37324金属氧化物半导体(Metal-Oxide-Semiconductor,MOS)管大电流驱动器提高驱动效率,实现推挽结构的后端驱动电路。闭环反馈电路的设计采用精密电阻将管电流的信号转换为等比例的电压信号引入到反馈环节,通过系统自身的闭环控制实现管电流的恒定,并保持高效率和低功耗。实验首先通过外接1.5?的功率电阻测量系统功率,测得输入功率为11 W,效率超过80%,符合灯丝电源的功耗指标要求;然后连接实际的X光管灯丝,经测试可正常工作,管流稳定度为0.227%。