S. Davis

The TFTR Neutral Beam Control and Data Acquisition System

This paper describes the compater control and data acquisition system for the Tokamak Fusion Test Reactor (TFTR) Neutral Beam injectors. The system provides hardware and software to permit remote operation of the four beamlines on TFTR, each containing up to three ion sources, and for a single-source beamline for the TFTR test stand.

Overview of the TFTR Computer System

The Tokamak Fusion Test Reactor (TFTR) is an experimental device built to study the physics and engineering problems of magnetically confined plasmas with temperatures and densities close to those that would exist in an actual fusion reactor. One of the prime goals of TFTR is to reach scientific breakeven, which is defined as the point where the amount of power used to maintain plasma temperatures is equal to the amount of power released through fusion reactions. The purpose of this paper is to give an overview of the computer system that provides the control, monitoring, data collection and analysis functions for TFTR.

Conceptual design for the TPX Central Instrumentation and Control System

The Tokamak Physics Experiment (TPX) is the next major device planned by the US fusion program. The device will be located at the Princeton Plasma Physics Laboratory and is currently scheduled to begin operation in the Spring of the year 2000. TPX will be a steady state device which is designed, constructed, and operated as a national experiment in collaboration with a number of major institutions. Most current fusion experiments operate in a pulsed mode and rely on data capture during the pulse with later data retrieval, analysis, and display. TPX, however, will require a real time data handling and analysis capability. This paper discusses the conceptual design for the TPX Central Instrumentation and Control (I&C) System. The design supports both the collaborative and steady state nature of the experiment. The design incorporates full integration of audio and video systems at the desktop and the use of standardized commercially available hardware and software systems. Key components of the Central I&C systems include guidance for subsystem design and prototype development and standardized operating stations for engineering and physics subsystems. It includes synchronization, safety, interlock, and controlled access systems and the control room facility with networks and data handling systems. The conceptual design includes a description of implementation philosophy as well as cost and schedules.

Expansion of the TFTR neutral beam computer system for D-T operations

The TFTR neutral beam computer system has expanded to provide an easy-to-use windowing and graphics environment for running the TFTR neutral beam injection system for D-T operations. Two SUN workstations are used for interactive analysis and display of neutral beam diagnostic and operational data. These systems are interfaced via Ethernet to another SUN computer which is used for data transfer and real-time analysis. The real-time analysis computer is linked to the TFTR Encore computer system via a DMA interface. Data acquisition and device control is performed on the Encore computers, and raw data is transferred via a memory-mapped approach to memory partitions and files on the SUN Analysis computer. Real-time analysis programs provide numerous displays to operators and engineers of operational data every 150 seconds. Physicists use X-window and OSF/MOTIF-based graphical user interfaces (GUIs) on the Diagnostic workstation to display interactive analysis of diagnostic data. These include X-window graphical displays of thermocouples, OMA, waterflow calorimetry, H-alpha duct and ion gauge data to the workstation. Neutral beam operations engineers also use a similar GUI to display interactive summary, power and ion source waveforms on the Operations workstation. In addition, these engineers have access to INGRES databases, which contain operational and analyzed data for the past several TFTR run periods. The Operations computer has a hard disk drive, which contains these INGRES databases and a database of restored analysis and raw data files. These files can be restored on demand from the TFTR computer system VAX cluster. The real-time Analysis computer also has a hard disk drive, which contains a database of the most recent analysis and raw data files.

Expansion of the TFTR neutral beam computer system

Previous TFTR (Tokamak Fusion Test Reactor) neutral beam computing support was based primarily on an Encore Concept 32/8750 computer within the TFTR Central Instrumentation, Control and Data Acquisition System (CICADA). The resources of this machine were 90% utilized during a 2.5-min duty cycle. Both interactive and automatic processes were supported, with interactive response suffering at lower priority. There were additional computing requirements and no cost-effective path for expansion within the Encore framework. Two elements provided a solution to these problems: improved price performance for computing and a highspeed bus link to the SELBUS. A Sun SPARCstation and a VME/SELBUS bus link allow offloading the automatic processing to the workstation. The details of the system, including the performance of the bus link and Sun SPARCstation, raw data acquisition and data server functions, application software conversion issues, and experiences with the UNIX operating system in the mixed platform environment, are described.<<ETX>>

Software Strategies and Hardware Upgrades to the PPL Data Acquisition System (DAS)

This paper describes upgrades to the Data Acquisition System for the Experimental Projects Department at PPPL, especially in support of the PBX-M upgrade to be completed this year. Hardware and software maintenance problems with the old configuration, consisting of a DEC KL-10 and eight PDP-11s, are described. The real-time software and hardware performance requirements and projections for CAMAC I/O and data analysis and display are presented. Described are three applications that have realtime requirements and are located on separate processors, connected to PPPLs VAX Cluster by an Ethernet link. Building upon a previous large software base, general-purpose subroutine libraries and utilities are being emphasized. The most useful of these are described. The use of software packages from DEC, third-party vendors, and the fusion community, is also described. The new approaches to software development that are being incorporated into the DAS efforts are discussed. Specific future challenges are also described.

Tools and frameworks supporting TPX and ITER design collaborations

The Tokamak Physics Experiment (TPX) and the International Thermonuclear Engineering Reactor (ITER) are the major national design efforts currently underway by the US fusion program. These design efforts are being performed at many different sites consisting of national laboratories, universities, and industrial partners. This paper presents the current status of work in support of expediting communication and enhancing the collaborative process by providing a framework of common tools and resources for all collaborators. The key components of this framework are common applications which support desktop mail, directory services, and convenient desktop access to project design documents. A discussion of the issues associated with the deployment, support, and future evolution of this framework will be presented.

Accommodating a significant increase in experimental data per shot on the TFTR central computing system

The recent change in the Tokamak Fusion Test Reactor (TFTR) program schedule has introduced a postponement of tritium operation for at least three years (currently scheduled for 1993). In the interim, TFTR research will place greater emphasis on understanding the physics of transport in tokamaks. This increased emphasis will result in the addition of more diagnostics and upgrades to existing diagnostics, significantly increasing the amount of data acquired for each TFTR experimental pulse. As the total data per shot increases, providing adequate facilities for acquiring, storing, analyzing, and archiving data will be a continual challenge. An overview of the functions of the TFTR central computing system is presented, and the areas which will need to be addressed to provide support for the larger data loads are identified.<<ETX>>