ICALEPCS07 - Classification:Process Tuning, Modeling, Automation, and Synchronization/

Process Tuning, Modeling, Automation, and Synchronization

Paper	Title	Page
ROAA02	Automatic Alignment System for the National Ignition Facility	486
	A. A.S. Awwal, S. W. Ferguson, B. Horowitz, V. J. Miller Kamm, C. A. Reynolds, K. C. Wilhelmsen LLNL, Livermore
	The Automatic Alignment System for the National Ignition Facility (NIF) is a large-scale parallel system that directs all 192 laser beams along the 300-m optical path to a 50-micron focus at target chamber in less than 30 minutes. The system commands 9,000 stepping motors to adjust mirrors and other optics. Twenty-two control loops per beamline request image processing services from a dedicated Linux cluster running Interactive Data Language tools that analyze high-resolution images of the beam and references. Process leveling assures the computational load is evenly spread. Algorithms also estimate measurement accuracy and reject off-normal images. One challenge to rapid alignment of beams in parallel is efficient coordination of shared devices, such as sensors that monitor multiple beams. Contention for shared resources is managed by the Component Mediation System, which precludes deadlocks and optimizes device motions using a hierarchical component structure. A reservation service provided by the software framework prevents interference from competing automated controls or the actions of system operators. The design, architecture and performance of the system will be discussed.
	Slides
ROAA03	Injection, Ramping and Extraction Timing for the Duke Booster	491
	G. Y. Kurkin BINP SB RAS, Novosibirsk S. F. Mikhailov, V. Popov, Y. K. Wu, S. M. Hartman FEL/Duke University, Durham, North Carolina
	A booster synchrotron capable of ramping from 0.25 to 1.2 GeV was recently commissioned at Duke University as part of the High Intensity Gamma Source upgrade. The triggering and timing system uses a combination of software logic and triggers, digital delay generators, and hardware synchronizers to coordinate the linac injector, booster synchrotron and electron storage ring. The injection system has been commissioned with a short pulse photo-injector linac into a single booster RF bucket and to two booster buckets separated by about half the circumference. It has also been commissioned with a long electron pulse from the injection linac into all 19 buckets. The extraction system, combined with short pulse kickers, can extract any of the booster's 19 electron bunches in to any of the storage ring's 64 bunches. Ramping is controlled by programmable VME based waveform generators triggered from the timing system. The system offers flexibility for commissioning and operations and provides a simple interface to the operator.
	Slides
ROAA04	XAL Online Model Enhancements for J-PARC Commissioning and Operation	494
	H. Ikeda Visual Information Center, Inc., Ibaraki-ken M. Ikegami JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken T. Ohkawa, H. Sako, G. B. Shen JAEA, Ibaraki-ken A. Ueno JAEA/LINAC, Ibaraki-ken C. K. Allen LANL, Los Alamos, New Mexico
	The XAL application development environment has been installed as a part of the control system for the Japan Proton Accelerator Research Complex (J-PARC) in Tokai, Japan. XAL was initially developed at SNS and has been described at length in previous conference proceedings (e.g., Chu et. al. APAC07, Galambos et. al. PAC05, etc.). We outline the upgrades and enhancements to the XAL online model necessary for accurate simulation of the J-PARC linac. For example, we have added permanent magnet quadrupoles and additional space charge capabilities such as off-centered and rotated beams and bending magnets with space charge. In addition significant architectural refactoring was performed in order to incorporate the current, and past, upgrades into a robust framework capable of supporting future control operations. The architecture and design of XAL is as important as its function, as such, we also focus upon the revised architecture and how it supports a component-based, software engineering approach.
	Slides
ROAA05	An Approach to Stabilizing Large Telescopes for Stellar Interferometry	497
	J. Sahlmann, A. Wallander, N. Di Lieto ESO, Garching bei Muenchen G. Vasisht Jet Propulsion Laboratory, Pasadena, California
	In stellar interferometry fringe-tracking is a method of stabilizing the Optical Pathlength Difference (OPD) from the observed astronomical source to the instrument detector via different telescopes in an interferometric array. At the ESO VLT Interferometer, which includes four 8.2 m class Unit Telescopes (UTs), stabilization to better than a tenth of the observing wavelength is required in order to improve the quality and sensitivity of fringe measurements on the interferometer's scientific instruments. Unfortunately, fast mechanical vibrations due to myriad sources in the observatory infrastructure couple to UT support structure and propagate to the large telescope mirrors. The mirror motions are fast and large (typically about a wavelength) and must be compensated for in real time. We have implemented a scheme to measure the accelerations imparted to the primary, secondary, and tertiary mirrors of the UTs via a grid of suitably placed accelerometers. The measured accelerations, coupled with a simple geometric model, are converted to optical pathlengths and canceled by a wideband feed-forward compensation to a downstream optical delay line.
	Slides
RPPA02	Linac RF Feed-forward Development at TLS	523
	K. T. Hsu, J.-Y. Hwang, D. Lee, K.-K. Lin, C. Y. Wu, K. H. Hu NSRRC, Hsinchu
	Performance of an electron linear accelerator is very important for synchrotron light source operation. Its performance in amplitude and phase of the RF field will decide the quality of extract beam. The RF feed-forward control is helpful to fixed amplitude and phase constant and keeps on stable beam extract. Design consideration and details of the implementation will be summary in this report.
RPPA10	Status of the Diamond Fast Orbit Feedback System	535
	M. G. Abbott, J. A. Dobbing, M. T. Heron, I. P.S. Martin, G. Rehm, I. Uzun, J. Rowland Diamond, Oxfordshire S. Duncan University of Oxford, Oxford
	We present the development of transverse orbit stability control at Diamond. We discuss the low latency feedback loop required to effectively suppress high-frequency noise, which informs the choice of network topology and processing units. We explore the use of the field-programmable gate array in the Libera beam position monitor as a communication controller and the vector unit of the PowerPC G4 in the compensator. System models and results from preliminary tests on the machine are shown.
RPPA11	MultiController: An Object Programming Approach to Introduce Advanced Control Algorithms for the GCS Large-Scale Project	538
	R. Barillere, A. B. Burmyakov, S. C. Cabaret, S. C. Cabaret CERN, Geneva H. Coppier ESIEE, Amiens A. Rachid UPJV, Amiens
	The GCS* project team at CERN uses a Model-Driven Approach with a Framework—UNICOS (UNified Industrial COntrol System)—based on PLC and SCADA* technologies. The first UNICOS versions were able to provide a PID**** controller, whereas the Gas Systems required more advanced control strategies. The MultiController is a new UNICOS object that provides the following advanced control algorithms: Smith Predictor, PFC (Predictive Function Control), RST, and GPC (Global Predictive Control). Its design is based on a monolithic entity with a global structure definition able to capture the desired set of parameters of any specific control algorithm proposed by the object. The SCADA system—PVSS—supervises the MultiController operation. It gives the user a wide choice of features through the MultiController object interface, including a recipe mechanism: the GCS experts are able to capture sets of relevant advanced control algorithm parameters to reuse them later. Starting by exposing the MultiController object design and implementation for a PVSS and Schneider PLC solution, this paper finishes by highlighting the benefits of the MultiController with the GCS applications. Gas Control SystemProgramming Language ControllerSupervisory Control And Data Acquisition**Proportional Integrative Derivative
RPPA14	Java Tool Framework for Automation of Hardware Commissioning and Maintenance Procedures	547
	J. M. Fisher, J. B. Gordon, L. J. Lagin, S. L. West, J. C. Ho LLNL, Livermore, California
	The National Ignition Facility (NIF) is a 192-beam laser system designed to study high energy density physics. Each beam line contains a variety of line replaceable units (LRUs) that include optics, stepping motors, sensors and other devices to control and diagnose the laser. During commissioning or subsequent maintenance of the laser, LRUs undergo a qualification process using the Integrated Computer Control System (ICCS) to verify and calibrate the equipment. The commissioning processes are both repetitive and tedious using remote manual computer controls, making them ideal candidates for software automation. Maintenance and Commissioning Tool (MCT) software was developed to improve the efficiency of the qualification process. The tools are implemented in Java, leveraging ICCS services and CORBA to communicate with the control devices. The framework provides easy-to-use mechanisms for handling configuration data, task execution, task progress reporting, and generation of commissioning test reports. The tool framework design and application examples will be discussed.
RPPA15	Initial Performance Results of the APS P0 Feedback System	550
	C. Yao, N. P. Di Monte ANL, Argonne, Illinois
	The Advanced Photon Source electron beam exhibits transverse instability when a large amount of charge is present in a single bunch. The P0 feedback system stabilizes the transverse motion of the beam under these circumstances. The initial requirement was to stabilize a single bunch of electrons in the horizontal plane. By implementing the stabilizer in an FPGA and using the parallel processing capabilities provided by this hardware, it is possible to stabilize 324 bunches per turn in both the horizontal and vertical planes. The stabilizer consists of 648 32-tap finite impulse response filters. This paper discusses the challenges in achieving this performance and some issues in interfacing to a Coldfire IOC running RTEMS. Initial test results of the system response are presented.
RPPA17	A Physics Based Approach for Magnet Control in a Booster and Storage Ring	553
	S. F. Mikhailov, Y. K. Wu, S. M. Hartman FEL/Duke University, Durham, North Carolina
	At Duke University, a booster synchrotron was recently commissioned as part of the HIGS upgrade. For the ramping magnet power supply controls, we followed an approach previously implemented for the Duke Storage Ring controls. The high-level operator interface is presented in terms of the physics quantities of the accelerator, i.e., the effective focusing strength of the magnets. This approach allows for a tighter integration of the control system with physics modeling programs and facilitates machine studies. The approach also simplifies operations of the accelerators by presenting an interface nearly independent of machine energy. For the booster, nonlinearities of the magnets, a result of its extremely compact footprint, are incorporated in to the low-level software while providing a high level of machine tunability. For the storage ring, feed forward compensations built on the effective strength of the magnets simplify tuning of the machine over a wide range of electron beam energies or wiggler settings. This approach provides for a good match to the diverse operational modes supported by the Duke Storage Ring.
RPPA19	Photon Diagnostic Station for TAC IR-FEL Test Facility	556
	I. Tapan UU, Bursa
	The Turkic Accelerator Center (TAC) project has been accepted by Turkish government. According to this project, a linac-based infrared oscillator free electron laser (FEL) will be constructed as a TAC test facility by the end of 2010. Planning work has been ongoing for the firt FEL facility building in Turkey. Both 20- and 40-MeV electron energies will be used to obtain infrared photons in the wavelength region of 1 to 100 micrometers. The IR FEL photons generated by two undulators will be transported through the respestive two photon beam lines to the experimental hall, where they are fed in to eight experimental station. Photon diagnostic station will be located in the experimental hall to measure the properties of the photon beam. In this work, the performance of the designed IR-FEL photon diagnostic station for the TAC test facility has been discussed.
RPPA20	A Fast Orbit Feedback for the ELETTRA Storage Ring	558
	D. Bulfone, V. Forchi', G. Gaio, L. Pivetta, M. Lonza ELETTRA, Basovizza, Trieste
	A fast global orbit feedback using digital Beam Position Monitor (BPM) detectors has been installed and commissioned at Elettra. The system uses 96 BPMs and 82 steerer magnets to correct closed orbit errors at a 10-kHz repetition rate. The feedback processing is performed by twelve VME stations equipped with commercial CPU boards running the Linux operating system with real-time extension and connected to each other by a low-latency fiber optic network. The system is fully controlled by a Tango based control system. A number of diagnostic and visualization software tools have been developed to easily operate the feedback and detect anomalous sources of orbit distortion. The operational experience and the achieved results are presented. Plans for further improvements of orbit stability are also discussed.
RPPA23	Initial Design of a Global Fast Orbit Feedback System for the ALBA Synchrotron	561
	M. Munoz, D. B. Beltran ALBA, Bellaterra (Cerdanyola del Vallès)
	This paper presents the initial design of the Global Fast Orbit Feedback (FOFB) system for the ALBA Storage Ring. The FOFB system is designed to reach a submicron stability of the electron beam working at frequencies of at least 100 Hz. It compensates the small perturbations produced by vibrations, electromagnetic noise and changes in the gap or phase of the insertion devices, etc. A description of the model is shown. The different subsystems have been identified and modeled: the BPM processor, the iron lamination and the vacuum chamber. The power converter supplies for the correctors play an important role in the system, and they have been designed (strength, resolution, bandwidth, voltage output) accordingly with the FOFB requirements. We have also studied the latency of the system (communication network, processing times). The orbit correction is computed by a PID controller. The simulations of the closed loop response show a damping of the perturbation between 0 and 100 Hz, although the system also introduces a small amplification of the noise just after this bandwidth. Finally the paper presents the initial design of the hardware architecture of the FOFB system.
RPPA29	A Feed-Forward Procedure to Counteract Orbit Distortions and Photon Beam Displacements from Insertion Device Operation at the SLS	573
	T. Schmidt, A. Streun, D. Zimoch, J. T.M. Chrin PSI, Villigen
	Insertion devices of various types provide light of high brilliance to experimenters at the SLS beamlines. Changes in the photon energy and polarization by movement of the ID gap and phase shift, however, cause orbit distortions that result in a displacement of the photon beam in both angle and position at the beamline. A feed-forward correction scheme has been developed to quantify and precisely correct these effects using designated correctors local to the photon source. The corrector settings are determined using an orbit configuration consisting of 73 digital BPMs and associated correctors; recently commissioned X-ray BPMs located at the beamline front-end are also included in the correction algorithmn and serve to constrain the photon beam to its specified position. The feed-forward table is finally implemented at the local processor level and applied at a rate of 10 Hz. A photon pointing stability at the sub-microradian level is achieved. The entire gap scan, feed-forward generation and subsequent verification can now be completed within 15 to 60 minutes depending on the complexity of the ID. The methodology of the procedure and high-level software framework is described.
RPPA30	Drift Compensation for the SNS Laserwire	576
	A. M. Barker, W. P. Grice, W. Blokland ORNL, Oak Ridge, Tennessee
	The Spallation Neutron Source (SNS) uses a laserwire to measure the transverse profiles in the Super Conduction Linac (SCL). The laser is located in a service building downstream from the SCL. Mirrors direct the laser light to a specific location to interact with the ion beam. Because of the long travel length of the light, up to 300 feet, minor mirror movements become large enough at the down stream station that the drift over time must be corrected. In this paper we describe how we correct for the drift and present our results.
RPPA32	Energy Ramping in BEPCII	582
	Q. Gan, J. Liu, H. L. Shi, J. C. Wang, X. L. Wang, C. H. Wang IHEP Beijing, Beijing
	The magnet power supply ramping synchronously is a fundamental procedure of the energy ramping of the BEPCII storage ring. The BEPCII has been put into synchrotron radiation operation (SR) (2.5GeV) research for 2 months after beams were successfully running in the Storage Ring with good beam performance. A software-based synchronization of the DAC setting on the power supplies is developed to achieve the relative magnet power supplies in the synchrotron ring ramped to the designed current synchronously. This paper introduces the schemes developed to perform energy ramping in the BEPCII storage ring and reports on the result of the operation carried out so far.
RPPA38	Fast Orbit Feedback System Upgrade in the TLS	597
	J. Chen, K. T. Hsu, S. Y. Hsu, K. H. Hu, C. H. Kuo, D. Lee, P. C. Chiu NSRRC, Hsinchu
	Orbit feedback system of the Taiwan Light Source (TLS) has been deployed for a decade. The loop bandwidth was limited by existing hardware. The system cannot remove perturbation caused by fast source. To improve orbit feedback performance, BPM system and corrector power supply are planned to upgrade within a couples of years. New digital BPM electronics will enhance functionality of the BPM system and replace analogy type BPM but due to limited resource, the BPM system will be a mixed type at this moment. The corrector power-supply is also replaced by high performance switching type power supply with wide bandwidth in the same time. It is expected that our upgrade will significantly improve performance of fast orbit feedback.