基于PC的光学速管色散段磁极间隙调节系统

描述了合肥国家同步辐射实验室光学速调管色散段磁极间隙调节系统的原理和结构。该调节系统已 ＮＳＲＬ的储存环自由电子激光实验中,效果良好,调节精度可高达１０＾－３ｍｍ。     

基于PC的光学速调管色散段磁极间隙调节系统

描述了合肥国家同步辐射实验室（ＮＳＲＬ）光学速调管色散段磁极间隙调节系统的原理和结构。该调节系统已应用在ＮＳＲＬ的储存环自由电子激光实验中,效果良好,调节精度可高达１０－３ｍｍ。     

光学速调管改造及磁场垫补

合肥相干谐波辐射实验装置的主体部分是光学速调管。为提高实验用电子束能量,将原光学速调管的对称结构改造为不对称结构。原光学速调管三段各自的积分场都很大,总的积分场很小,三段不能独立可调。改造后的光学速调管需要三段独立可调,每段的积分场都必须很小。对改造后保留的辐射段磁场进行垫补和调试,使它的积分场和相位误差得到了有效减小。     

合肥储存环相干辐射实验的参数优化研究

对光学速调管相干辐射的物理过程进行了研究,并编制了三维模拟程序,利用实测测磁场值,分析了影响自发辐射调制率的主要因素,提出了优化的激光功率和Nd值。     

NSRL储存环相干谐波自由电子激光实验总体布局

国家同步辐射实验室(NSRL)正在开展储存环相干谐波自由电子激光研究,目标是获得266nm相干辐射输出,并且获得较高的相干增强因子。给出实验的总体布局,包括电子束、种子激光及光学速调管的性能,介绍了种子激光扫描聚焦系统、同步系统、光学速调管磁极间隙控制系统、磁场测量系统及辐射测量系统。     

SXFEL装置上速调管输入输出特性曲线的线性化

在上海软X射线自由电子激光(Soft X-ray Free-electron Laser,SXFEL)中的微波低电平控制系统中,通过对各速调管的输出信号进行测量和控制,保证加速器的稳定运行并且达到技术指标。另一方面,SXFEL中的脉冲速调管的输入输出特性存在非线性的关系,这种电子管放大器不理想的非线性特性会导致微波低电平(Low Level Radio Frequency,LLRF)控制系统调节的效率降低。基于SXFEL装置,采用基于现场可编程门阵列(Field Programmable Gate Array,FPGA)的数字预失真方法,在LLRF控制系统中设计了一套实现高功率速调管放大器线性化的在线系统。S波段加速装置和其相应的东芝E3730A速调管及高压调制器和低电平系统实地测试结果表明,在LLRF控制系统中建立的在线系统能够有效补偿速调管带来的非线性问题,提高微波低电平控制系统的精度及准确性。     

相干谐波辐射实验的测量和控制系统

电子束和种子激光一同通过光学速调管时,产生相干谐波辐射,这是获得短长波相干光的一种很有希望的途径。为产生相干辐射,光学速调管波荡器磁极间隙,种子激光波长和电子能量三者必须满足共振条件,电子束团和种子激光脉冲在时间上必须严格同步。为使某次相干谐波辐射达到极大值,光学速调色散段磁极间隙必须调节,介绍了相干谐波辐射的测量、种子激光与电子束的同步和光学速调管极间隙调节系统。     

基于光学渡越辐射方法的实时电子能谱测量系统

针对加速器技术发展和应用对能谱测量精度、速度要求的不断提高,提出基于光学渡越辐射方法和实时能谱测量方案,给出了该方案的初步解决方法,并对各个实现细节给与描述,最终给出在中国科学院高能物理研究所自由电子激光（BFEL）实验室所得的阶段性实验结果。在现有实验条件下,所得OTR光宽20mm,与理论计算值相吻合。     

基于PC机的步进电机控制系统

研制成功了ＳＭＣ－１步进电机控制接口板并由此组成了步进电机控制系统，已将此系统应用于ＢＳＲＦ荧光实验站，导弹仿真系统等领域，效果良好。     

可编程逻辑控制系统在北京自由电子激光装置的实验物理和工业控制系统中的应用

在北京自由电子激光(BFEL)装置的搬迁改造工程中,开关机系统的控制采用基于实验物理和工业控制系统(EPICS)的可编程逻辑控制(PLC)控制系统,它具有安全可靠、操作简单、易于扩展、便于通讯等优点.本文介绍了该控制系统的设计和开发,包括系统软硬件的结构设计以及系统的EtherNet/IP网络通讯.     

Analysis of the measurement field of the optical klystron

The measured fields of the optical klystron in NSRL (National Sychrotron Radiation Laboratory)are, given, incluing the distribution on the axis,and the integrated filed distribution.the harmonic magnet fild and the spectra of the spontaneous emission are analyzed,and the multiple fild is presented by fitting the diagram.The influence of the integrated fild on the colse orbit of the beam and on the operation parameters of the storage ring ,and the compensation in the oexperiment are also discussed.     

具有步进电机控制和定标器功能的PC机接口板

研制了具有步进电机控制和定标器两种功能的ＰＣ机接口板，编写了相应的驱动程序，并在北京同步辐射实验室形貌学实验站用于四刀狭缝原控制和衍射数据的获取。     

基于PC104的小型氡室测控系统

氡室是刻度测氡仪器的一种标准装置,在动态保持氡浓度稳定性数学模型基础上,采用PC104设计实现了氧室自动测控系统。对氧浓度进行实时监控,根据氧量控制参数进行氧的自动补给和排放。实现了动态保持小型氧室中氧浓度的稳定性。     

Evaluation of mean time between accidental interruptions for accelerator klystron systems based on the reliability engineering method

Frequent beam trips as experienced in existing high-power proton accelerators may cause thermal fatigue in Accelerator-Driven System components. In order to overcome the beam-trip problem, the beam-trip frequencies were estimated based on operational data on existing accelerators. However, there are at least three methods to calculate the mean time between accidental interruptions (MTBI) for one of the accelerator components, the klystron system. In this study, the four types of MTBI for the klystron systems of an electron/positron injector linear accelerator at the High Energy Accelerator Research Organization were compared based on the same operational data. In the analysis, the stop events of the klystron systems were classified, and the MTBI for the klystron systems was calculated using the Kaplan–Meier (KM) estimation, which is a representative non-parametric reliability method. As a result, the mean value of the MTBI found by the KM estimation was 57.3 ± 6.5 hours. On the other hand, the mean values of the MTBI found by the three traditional methods were 30.9 ± 2.4, 32.0 ± 2.3, and 50.4 ± 5.9 hours. The mean values for the ratios of the MTBI found by the KM estimation, to the MTBI found by the traditional estimation, were 1.67 ± 0.07, 1.58 ± 0.06, and 1.14 ± 0.01, respectively. Although these results are obviously different from traditional results, it appears that the present estimation is suitable for the MTBI for accelerator components.     

Dynamic development model for long gap discharge streamer-leader system based on fractal theory

Establishing a long air gap discharge model considering the streamer-leader transition and randomness of the discharge path is of great significance to improve the accuracy of discharge characteristic prediction and optimize external insulation design. Based on fractal theory and thermal ionization theory of streamer-leader transition, this work establishes a dynamic development model for the long air gap discharge streamer-leader system, which includes streamer inception, streamer development, leader inception, development of streamer-leader system and final jump. The positive discharge process of a 3 m rod plate is simulated to obtain the fractal distribution of the discharge path and the law of leader development for comparison with the discharge test results. The results show that the simulation model is similar to test results in the development characteristics of leader path distribution, each stage time and leader velocity. Finally, a simulation calculation of a 50% breakdown voltage of the rod-plate gap and ball-plate gap is carried out, with results fairly consistent with test data, proving the effectiveness and practicality of the model.     

NSRL储存环平面控制网的实测与平差分析

NSRL平面控制网的建立是基于准直测量方案和测量仪器,合理布设增加的磁铁基准点,使其有效反映磁铁位置变化,正确布设地标点和测量过渡点以满足多站测量所需.依据准直方案选取仪器进行实地测量,获得可靠数据.针对实测数据,结合平差理论,依据各部件基准点的理论位置,利用多种有效的平差方法处理数据,获取二极磁铁点位误差及误差参数,建立所有测量网点的数据库,结合实际分析误差来源,并对实测过程进行修正.     

高增益自由电子激光光阴极注入器驱动激光系统设计考虑

高增益自由电子激光对电子束团提出了高品质要求 ,只有光阴极微波电子枪能够达到这一目标。光阴极微波电子枪的驱动激光器是这一系统的关键之一。北京大学重离子物理研究所设计的驱动激光系统的指标是提供 2 6 0nm、6～ 8ps宽、5 0 0 μJ的激光脉冲。系统主要由半导体泵浦的钛蓝宝石振荡器、Nd∶YAG调Q泵浦源、再生式放大器、倍频器等组成。系统中采用了腔长调整锁模技术以及相位稳定反馈装置 ,目的是使激光脉冲的时间抖动小于 1 0 ps。     

基于Windows CE的HIRFL-CSR前端控制系统设计与实现

介绍了一个基于Windows CE的嵌入式分布控制系统,系统基于以太网和现场总线连接,节点用嵌入式平板计算机实现。给出了系统的硬件组成和软件设计,该系统已应用于HIRFL-CSR前端控制系统。