FPGA技术在脉冲中子源数据采集系统的设计与实现

介绍了一种基于FPGA、单片机及USB接口技术的脉冲中子源数据采集系统,并重点对FPGA的设计进行了阐述。     

基于CAMAC总线的交替式数据采集及实时监控系统研究

进行了一种称为交替式数据采集及实时监控系统的研究。该系统不仅能实现以较高频率进行任意时间的数据采集,还能在放电过程中以图形方式实时显示等离子体的各种参数供实验人员在线分析及控制。     

HT-7超导托卡马克MHD实时检测与处理系统的设计与实现

磁流体不稳定性（MHD）是影响HT-7长脉冲放电的一个重要因素,通常可以通过调制低杂波电流驱动的方法来抑制MHD。实验发现全程调制低杂波电流驱动会降低低杂波的驱动效率。我们采用了主动反馈调制低杂波电流驱动的方法,设计并实现了MHD的实时检测与处理系统。研究结果表明,该系统既可以实时地抑制MHD,又不降低低杂波驱动效率。     

多功能网络化核数据获取和处理系统

应用网络技术将多个功能不同、相互独立的以PC微机为基础组成的核数据获取和处理子系统有机互联,组成了一种新型的多功能网络化核数据获取和处理系统,探讨了系统的最佳组成模式、工作原理及实现方法,给出了系统在2．5MeV静电加速器上进行团簇特性研究的初步结果。     

Distributed digital real-time control system for TCV tokamak

A new digital feedback control system (named the SCD “Système de Contrôle Distribué”) has been developed, integrated and used successfully to control TCV (Tokamak à Configuration Variable) plasmas. The system is designed to be modular, distributed, and scalable, accommodating hundreds of diagnostic inputs and actuator outputs. With many more inputs and outputs available than previously possible, it offers the possibility to design advanced control algorithms with better knowledge of the plasma state and to coherently control all TCV actuators, including poloidal field (PF) coils, gas valves, the gyrotron powers and launcher angles of the electron cyclotron heating and current drive system (ECRH/ECCD) together with diagnostic triggering signals. The system consists of multiple nodes; each is a customised Linux desktop or embedded PC which may have local ADC and DAC cards. Each node is also connected to a memory network (reflective memory) providing a reliable, deterministic method of sharing memory between all nodes. Control algorithms are programmed as block diagrams in Matlab-Simulink providing a powerful environment for modelling and control design. The C code is generated automatically from the Simulink block diagram and compiled, with the Simulink Embedded Coder (SEC, formerly Real-Time Workshop Embedded Coder), into a Linux shared library (“.so” file) and distributed to target nodes in the discharge preparation phase. During the TCV discharge, an application on each node is executed that dynamically loads the shared library at runtime. In order to obtain reliable and reproducible real time execution of the algorithm, all interrupts to the CPU on each node are suspended just before firing the shot and re-enabled afterwards. Since installation, the new digital control system has been used for a multitude of plasma control applications, ranging from basic experiments of coil current and density control to advanced experiments of MHD (magnetohydrodynamics) and plasma profile control, as well as real-time plasma transport simulations. Recently, a real-time version of a plasma equilibrium reconstruction code was developed and implemented, providing the future possibility to control the plasma shape and profiles directly during the discharge evolution. This paper presents the architecture of the new control system, its integration into the TCV plant and a sample of control applications used for TCV plasma discharges.     

基于CBM-TOF探测器无触发数据获取系统的压缩算法研究

针对CBM-TOF(Compression Baryon Material experiment-Time of flight detector)探测器采用的无触发数据获取系统所产生的数据流,本文提出一套完整的数据压缩算法,该算法通过提取数据流中与粒子信息相关的数据,并将数据配对成脉冲信号做进一步的数据筛选来完成。算法通过三个步骤完成对数据的压缩处理,分别是有效性验证、排序及脉宽筛选。有效性验证将初步筛选数据,保留粒子到来的时刻信息(绝对时间/相对时间),再通过后面两个步骤将符合行为的脉冲提取出来。通过压缩来自COSY的束流测试的数据,算法的正确性和有效性得到了验证,数据的压缩率达到94.5%以上,并且完整地保留了有用的数据信息。本算法减轻了无触发数据获取系统链路上数据流的压力,高效快速地将原始数据中有价值的信息提取出来,基本完成了针对CBM-TOF数据预处理的工作要求,对TOF探测器的数据重组有重要的意义。     

Modular software for MAST multi-technology data acquisition system

The MAST (Mega-Amp Spherical Tokamak) data acquisition system is being radically upgraded. New hardware with completely different control interface and logic has been installed on all system levels from front-end devices to plant control. MAST plant control has been moved from VMS to a Windows-based OPC system. Old CAMAC and VME units are being replaced by cPCI and PXI units. A number of CAMAC crates have been upgraded with new Ethernet controllers supporting useful front-end devices.The upgrade is being performed without disturbing operations; the data acquisition units are being replaced gradually. Such an upgrade is possible due to the structure of the MAST data acquisition system which is build as a set of autonomous units, each one controlled by a computer. Modern computers are capable of controlling several units, and this has been the major opportunity and challenge because it radically changes the unit control logic. As a result practically all system components had to be redesigned.The new unit software is a step in system evolution towards greater flexibility and universality. Each unit can now manage multiple data files, possibly with different formats, and many units can be hosted on the same computer. This feature is provided by a message proxy server. Each unit is controlled independently and transparently, exactly like a stand-alone unit. A message interface has been modified for consistent handling of new functions. The unit software supports event-triggered and real-time data acquisition at the system level. New software has been developed for a number of new hardware devices, and the device modules for all usable old devices have been rewritten to operate with the new control interface.The new software allows units to be upgraded even during operations. The system structure and logic provide easy extension. The system as a whole or system design elements could also be used on other fusion facilities.     

Design and application of an EPICS compatible slow plant system controller in J-TEXT tokamak

J-TEXT tokamak has recently implemented J-TEXT COntrol, Data Access and Communication (CODAC) system on the principle of ITER CODAC. The control network in J-TEXT CODAC system is based on Experimental Physics and Industrial Control System (EPICS). However, former slow plant system controllers in J-TEXT did not support EPICS. Therefore, J-TEXT has designed an EPICS compatible slow controller. And moreover, the slow controller also acts the role of Plant System Host (PSH), which helps non-EPICS controllers to keep working in J-TEXT CODAC system. The basic functionalities dealing with user defined tasks have been modularized into driver or plug-in modules, which are plug-and-play and configured with XML files according to specific control task. In this case, developers are able to implement various kinds of control tasks with these reusable modules, regardless of how the lower-lever functions are implemented, and mainly focusing on control algorithm. And it is possible to develop custom-built modules by themselves. This paper presents design of the slow controller. Some applications of the slow controller have been deployed in J-TEXT, and will be introduced in this paper.     

基于氦喷嘴带传输装置的微机数据获取系统

介绍一套特殊的核物理实验装置，它由氦喷嘴装置，带传输装置和微机数据获取与分析系统组成，氦喷嘴装置和带传输装置将反应物从反应室传送到探测器前面，同时给出一个同步信号来控制获取系统，获取系统准确识别控制信号，产生一个明显的标识符来标记不同的样品。本系统对短寿命远离稳定线纱的研究有独特的优势。     

Fast data acquisition system based on digital oscilloscopes for fluctuation measurements in a long pulse JT-60U tokamak plasma

We have developed a new data acquisition (DAQ) system with fast sampling rate for fluctuation measurements in a long pulse JT-60U tokamak plasma. This system is based on a powerful digital oscilloscope, which has a large acquisition memory up to 50 Mwords/ch, 1 MHz sampling rate and 16 bits high resolution AD convertors. The system is composed of plural digital oscilloscopes and mass storages. On this system, most of data acquisition processes are executed at each digital oscilloscope. This feature of the system leads to an advantage that the processing loads are distributed among the digital oscilloscopes. This system has been successfully employed for measurements of various fluctuations obtained through magnetic probes, beam emission spectroscopy and so on. The size of the acquired data using this system has reached up to 10 GB/shot so far. It has demonstrated that this system is very powerful for data acquisition of multi-channeled signals with high time resolution in a long pulse plasma.     

Design and implementation of data acquisition system for magnets of SST-1

The magnet system of the Steady-State Superconducting Tokamak-1 at the Institute for Plasma Research, Gandhinagar, India, consists of sixteen toroidal field and nine poloidal field. Superconducting coils together with a pair of resistive PF coils, an air core ohmic transformer and a pair of vertical field coils. These magnets are instrumented with various cryogenic compatible sensors and voltage taps for its monitoring, operation, protection, and control during different machine operational scenarios like cryogenic cool down, current charging cycles including ramp up, flat top, plasma breakdown, dumping/ramp down and warm up. The data acquisition system for these magnet instrumentation have stringent requirement regarding operational flexibility, reliability for continuous long term operation and data visualization during operations. A VME hardware based data acquisition system with ethernet based remote system architecture is implemented for data acquisition and control of the complete magnet operation. Software application is developed in three parts namely an embedded VME target, a network server and a remote client applications. A target board application implemented with real time operating system takes care of hardware configuration and raw data transmission to server application. A java server application manages several activities mainly multiple client communication over ethernet, database interface and data storage. A java based platform independent desktop client application is developed for online and offline data visualization, remote hard ware configuration and many other user interface tasks. The application has two modes of operation to cater to different needs of cool-down and charging operations. This paper describes application architecture, installation and commissioning and operational experience from the recent campaigns of SST-1.     

Test bed for real-time image acquisition and processing systems based on FlexRIO,CameraLink, and EPICS

Image diagnostics are becoming standard ones in nuclear fusion. At present, images are typically analyzed off-line. However, real-time processing is occasionally required (for instance, hot-spot detection or pattern recognition tasks), which will be the objective for the next generation of fusion devices. In this paper, a test bed for image generation, acquisition, and real-time processing is presented. The proposed solution is built using a Camera Link simulator, a Camera Link frame-grabber, a PXIe chassis, and offers software interface with EPICS. The Camera Link simulator (PCIe card PCIe8 DVa C-Link from Engineering Design Team) generates simulated image data (for example, from video-movies stored in fusion databases) using a Camera Link interface to mimic the frame sequences produced with diagnostic cameras. The Camera Link frame-grabber (FlexRIO Solution from National Instruments) includes a field programmable gate array (FPGA) for image acquisition using a Camera Link interface; the FPGA allows for the codification of ad-hoc image processing algorithms using LabVIEW/FPGA software. The frame grabber is integrated in a PXIe chassis with system architecture similar to that of the ITER Fast Controllers, and the frame grabber provides a software interface with EPICS to program all of its functionalities, capture the images, and perform the required image processing. The use of these four elements allows for the implementation of a test bed system that permits the development and validation of real-time image processing techniques in an architecture that is fully compatible with that of the ITER Fast Controllers. This paper provides a specific example of a pattern search in a movie, its real-time implementation, and a performance analysis of the entire platform.     

基于PCI接口的瞬态波形记录仪

阐述了一套基于PCI接口采样率达200M／s的瞬态波形记录仪的结构及其性能。该系统适用于对高速、宽带的瞬态信号进行数字化处理。     

The upgrade of the J-TEXT experimental data access and management system

The experimental data of J-TEXT tokamak are stored in the MDSplus database. The old J-TEXT data access system is based on the tools provided by MDSplus. Since the number of signals is huge, the data retrieval for an experiment is difficult. To solve this problem, the J-TEXT experimental data access and management system (DAMS) based on MDSplus has been developed. The DAMS left the old MDSplus system unchanged providing new tools, which can help users to handle all signals as well as to retrieve signals they need thanks to the user information requirements. The DAMS also offers users a way to create their jScope configuration files which can be downloaded to the local computer. In addition, the DAMS provides a JWeb-Scope tool to visualize the signal in a browser. JWeb-Scope adopts segment strategy to read massive data efficiently. Users can plot one or more signals on their own choice and zoom-in, zoom-out smoothly. The whole system is based on B/S model, so that the users only need of the browsers to access the DAMS. The DAMS has been tested and it has a better user experience. It will be integrated into the J-TEXT remote participation system later.     

便携式双通道多道核谱仪中数据采集系统的设计

介绍应用FPGA为核心芯片配合峰保电路、高速A／D转换电路以及USB接口电路实现了便携式双通道多道核谱仪中数据采集系统；给出了软硬件的实现方案和实验结果；该系统具有采集精度高、传输快等特点，同时为进一步实现多通道信号采集提供了很好的参考价值。     

X射线工业CT中的数据采集

介绍了X射线工业CT中数据采集的一种方法.将X射线转换成与之成线性关系的微弱电流信号,通过检测电流信号测量出X射线的相对强度.这种采集方法可根据X射线的剂量强度,灵活的改变电流检测电路的参数,因此适用于不同能量级的X射线的采集.该X射线采集方法已经成功应用工业CT数据采集系统中.     

The development of data acquisition and processing application system for RF ion source

As the key ion source component of nuclear fusion auxiliary heating devices, the radio frequency(RF) ion source is developed and applied gradually to offer a source plasma with the advantages of ease of control and high reliability. In addition, it easily achieves long-pulse steady-state operation. During the process of the development and testing of the RF ion source, a lot of original experimental data will be generated. Therefore, it is necessary to develop a stable and reliable computer data acquisition and processing application system for realizing the functions of data acquisition, storage, access, and real-time monitoring. In this paper, the development of a data acquisition and processing application system for the RF ion source is presented. The hardware platform is based on the PXI system and the software is programmed on the Lab VIEW development environment. The key technologies that are used for the implementation of this software programming mainly include the long-pulse data acquisition technology, multithreading processing technology, transmission control communication protocol, and the Lempel–Ziv–Oberhumer data compression algorithm. Now, this design has been tested and applied on the RF ion source. The test results show that it can work reliably and steadily. With the help of this design, the stable plasma discharge data of the RF ion source are collected,stored, accessed, and monitored in real-time. It is shown that it has a very practical application significance for the RF experiments.     

基于AVR单片机与USB接口的高速多道核数据采集系统

介绍了多个探测通道组成的多道核数据采集系统,对4 MeV静电加速器核辐射进行监测防护.各个通道采用AVR单片机ATmega128作为主控制器,通过基于CH375构成的USB接口实现数据传输.经实验测试,该系统采集速度快,死时间小,计数率高.其探头部分在更换相应的探测传感器和稍作参数调整后,便可同时探测分析γ、X和快中子等不同的放射性辐射,适用于作为大范围场地的辐射监测系统.     

多通道高速数据采集与处理装置的研制

介绍了一种多通道数字信号处理装置的基本技术指标、基本结构和系统工作原理。它包括前端放大、A／D转换、数据缓存FIFO、数字信号处理等电路设计以及系统的设计。本系统具有较通用性,可以应用于各种需要高速数据采集与高速数据处理的仪器之中。