合肥光源200MeV直线加速器束流流强测量系统的改进

用ＰＣ机经扩展机箱完成对８路束流信号的采集,处理,并可同时显示,打印全部８路束流流强信号于一幅,也可任选其中一路帮单幅放大显示,此设备提高了直线加呸器束流流强信号的测量精度,并方便了直线加速器调机人员的操作。     

数字化平均流强测量方法研究

平均流强测量可用DCCT或ICT探头,ICT探头有很强的抗电磁干扰能力,但测量精度不高.用高精度A/D转换器和等效采样测量算法使ICT探头组成的平均流强测量系统有较高的测量精度.本文主要介绍了基于ICT探头的平均流强测量系统、测量算法和实验室测试结果.     

压电变压器原理研究及特性测试

研究了一种可用于粒子加速器的压电变压器结构及工作原理，并采用等效电路和实验相结合的方法测试了压电变压器的若干工作特性。     

RF front-end for digital beam position monitor signal processor

RF circuit board has a significant impact on performance of the Digital Beam Position Monitor (DBPM) in storage ring of a synchrotron radiation facility.In this paper,a front-end RF board is designed for DBPM,and schematics of the RF board and the test results are given.In view of the inevitable inconsistency in the multi-channel circuit,a calibration circuit is designed to reduce such an influence.The test results show that the calibration method is useful for beam current dependence which is sensitive to channels inconsistency.     

Equivalent circuit model for the insulated core transformer

The design of the insulated core transformer(ICT)needs to consider the flux leakage effects.An equivalent linear circuit model is proposed based on the principle of duality.It is composed by two types of leakage inductances:conventional leakage between windings and special leakage introduced mainly by the insulation gaps.The values of leakage inductances depend on the dimensions of the core,gaps,or windings and the property of magnetic materials.The circuit allows for quantitatively evaluating influences of ICT internal parameters on its output properties.The winding self- and mutual inductance matrix is mathematically converted to derive the inductance formula.As an example,the leakage parameters of a sixstage two-dimensional(2D) ICT are calculated and analyzed.     

上海光源直线加速器的弱流强运行

上海光源(SSRF)直线加速器正常运行时,重复频率2 Hz,单束团脉宽1 ns,电荷量1 nC。近年来,国际同步辐射领域发展起来的恒流注入模式要求直线加速器以弱流强运行,在相同的重复频率和脉宽下,单脉冲电荷量越小越好,此方法重复性较好。本文在理论计算基础上,结合实验,给出了弱流强稳定运行的实现方法,确定了在Top-up模式下,直线加速器的脉冲电荷量为0.1 nC。     

Implementation and integration of a systematic DBPM calibration with PLL frequency synthesis and FPGA

Beam current dependence resulted from nonlinearity and asymmetry of the four channels of digital BPM(Beam Position Monitor) processor deteriorates the BPM performance.A systematic solution based on signal source calibration tactics has been carried out to rectify this defect.It is optimized for implementation in FPGA.Mathematical illustrations of the calibration method,hardware and software design and implementation are presented.A signal source circuit using frequency synthesis technique is designed as calibration standard.Data acquisition system using JAVA web technology and Ethernet is introduced.Integrated FPGA implementation code architecture is presented,and experimental test results show that the method implemented in FPGA is feasible.Compared to other methods,our approach can rectify the nonlinearity and asymmetry simultaneously.The whole solution is integrated into the DBPM processor and can be executed online.     

多功能组合同步辐射束线光束探测器

光束探测器是同步辐射束线工程技术的重要组成部分,用以监测x光束线的位置、强度及空间分布等参数,因而对束线的准直、性能分析及实时监测具有重要意义。基于北京同步辐射实验室1W1B—XAFS束线工程项目,我们研制开发了一种应用光电二极管的光束探测器。该探测器与固定光阑、铍窗组合为一体,结构简单可靠,造价低,主要用于X光束线的准直及束流强度实时监测。1W1B—XAFX束线运行两年以来,探测器工作正常,达到了设计的目标。本文介绍了该种束流探测器的结构原理,及由此构成的一套完整的束流监测系统。同时也讨论了探测器的工作模式及测试结果。     

用于核子皮带秤的弱电流放大器崐和输出电路

研制了弱电流放大器和输出电路，其最大非线性误差为±０．０６％。实验证明其性能稳定可靠，可应用于核工业仪表。     

环形单针双束流截面测量技术

利用一个三维环形探针对离子束进行旋转扫描，可以同时测量到两个束流截面的大小和位置，估算出二截面附近的聚焦梯度以及束腰的移动。     

基于ARM与FPGA的运动控制平台研究

介绍了基于ARM与FPGA的实时束流截面测量的嵌入式平台,讨论了电机控制器子系统的硬件接口设计,通过ARM的外围总线实现了ARM与FPGA的接口,并采用Linux操作系统对FPGA设备进行驱动开发。自主开发的硬件接口板用于测试ARM与FPGA实现方案以及整机集成后的硬件性能。实验测试表明,硬件接口板能有效实现电动控制,原运动控制器定位精度为1μm,现平台定位精度达2μm,数量级上满足要求,可用于后续FEL设备升级。     

基于示波器嵌入式IOC技术的逐束团位置监测系统研制

为研究尾场引起的束团不稳定性,本工作开发了基于高速宽带示波器嵌入式IOC的逐束团位置测量系统。该系统通过直接获取加速器储存环中钮扣型电极的原始束流信号,进行在线计算独立的水平和垂直方向的逐束团位置。介绍了此系统的需求分析、硬件结构以及嵌入式IOC软件结构。利用在上海光源储存环上获取的逐束团位置数据,对系统性能进行了评估。实验显示,不同束团感应到的工作点及横向振荡振幅与束团编号间的依赖关系,结果证明该系统是一个有效的机器研究工具。     

国家同步辐射实验室壁流探测器的研制

介绍了国家同步辐射实验室用于测量束流流强的壁流探测器，并分析了壁流流强小于束流流强的几种主要因素。最后给出了实际测量结果。     

A real-time beam loss monitoring system for storage ring of SSRF

In this paper we report the real-time beam loss monitoring (BLM) system at the storage ring of SSRF.The BLM-XS detectors and Ethernet data acquisition system are used in this system.Some applications and experiments of the BLM system are also presented.The BLM system provides dynamic information of beam loss for the storage ring,and is helpful to ensure the facility commissioning,investigate the problems of machine,optimize the machine parameters and further increase the beam lifetime.     

电子入射角对束流传输系数和能量沉积的影响

利用数值方法研究了不同能量 (0 .4— 1.4MeV)的电子束以不同的入射角穿透不同厚度碳靶的束流传输系数和能量沉积。计算结果表明 ,随着电子束入射角的增大 ,束流的传输系数减小 ,而较小入射角 (接近垂直入射角 )的电子在靶材料中穿透深度更大 ;能量为 1.0— 1.4MeV的电子束当入射角在 6 0°— 70°时在碳靶单位体积中沉积的能量最大