THP —  Poster 2   (18-Oct-18   15:30—17:00)
Chair: C.H. Kuo, NSRRC, Hsinchu, Taiwan
Paper Title Page
Norm Optimal Iterative Learning Control Design for J-PARC LINAC LLRF System  
  • S. Li
    J-PARC, KEK & JAEA, Ibaraki-ken, Japan
  The beam current in J-PARC LINAC will increase to 60 mA in the future. In order to deal with more serious beam loading effect,an iterative learning control method was put forward. However, in previous method controller uses only proportional control. Taking into account the actual situation, its control performance still has room for improvement. For this reason, an iterative learning control based on norm optimization algorithm is applied to LLRF simulation model. The control method and result will be summarized in this paper.  
THP02 Current Status of the RAON Machine Protection System Development -1
THPI2   use link to see paper's listing under its alternate paper code  
  • H. Jin, Y. Choi, S. Lee
    IBS, Daejeon, Republic of Korea
  For the RAON accelerator that transport beams with high energy and power, a machine protection system (MPS) that protects each device from sudden beam loss is necessary. For this reason, we have been preparing for the development of the MPS with the start of the RAON accelerator construction. For effective MPS operation and stable accelerator operation, we divided the MPS into four subsystems: fast protection system, slow interlock system, run permit system, and post-mortem system. Among them, the FPGA-based fast protection system and the PLC-based slow interlock system have been tested by prototypes and are currently working on the mass production. The run permit system and the post-mortem system are also undergoing basic design and software development. In this paper, we will describe the progress of the MPS development through detailed hardware and software development in the RAON accelerator and explain the future plans.  
Marvin Update ' the Robotic Sample Mounting System at the Embl-Hamburg  
THPI3   use link to see paper's listing under its alternate paper code  
  • U. Ristau, S. Fiedler
    EMBL, Hamburg, Germany
  In this article we give an overview about the controls of the robotic sample mounting system Marvin in user operation at the DESY Petra III synchrotron Beamlines of the EMBL. Two protein crystallography Beamlines each equipped with the in house build robotic sample mounting system are in user operation. The controls of the sample mounting system ‘Marvin' and especially new developments to decrease down times as well as system recovery routines will be described in detail.  
poster icon Poster THP03 [1.910 MB]  
Real-time and Detailed Provision of J-PARC Accelerator Operation Information from the Accelerator Control LAN to the Office LAN  
THPI4   use link to see paper's listing under its alternate paper code  
  • S. Yamada
    J-PARC, KEK & JAEA, Ibaraki-ken, Japan
  J-PARC Main Ring (MR) is a high-intensity proton synchrotron whose control system is developed based on EPICS. It started its beam operation in 2008, and since 2009 has been delivering beam to the T2K neutrino experiment and hadron experiments. Over the past decade, MR have become more sophisticated and more stable driving is required. Along with this, demands arose from users and experts of equipment such that acquiring detailed and real-time information on the apparatus from the office LAN. On the other hand, the accelerator control system is quarantined from the office LAN with firewall for security reasons. Therefore, despite being intentional or not, manipulating any equipment in the accelerator control LAN shall be prohibited from the office LAN. This article describes construction and prospects of such an one-way gateway system such that information is relayed via EPICS from accelerator control LAN to the office LAN while minimizing influence in the opposite direction.  
THP05 Development and Current Status of KURAMA-II -1
THPI5   use link to see paper's listing under its alternate paper code  
  • M. Tanigaki
    Kyoto University, Research Reactor Institute, Osaka, Japan
  KURAMA-II, a successor of a carborne gamma-ray survey system named KURAMA (Kyoto University RAdiation MApping system), has been developed and applied to various activities related to the nuclear accident at TEPCO Fukushima Daiichi Nuclear Power Plant in 2011. KURMA-II has established its position as an effective method for the radiation monitoring method in environment on a long-term basis. The development of KURAMA-II is still on the way to extend its application areas such as the trial to port the system to a single-board computer or the development of cloud services of data management for the users who don't have capabilities to manage the data processing system. In this paper, the current status of KURAMA-II on its developments and applications along with some results from its applications are introduced.  
THP06 Reliability Improvement for the Insertion Device Control in the TPS -1
THPI6   use link to see paper's listing under its alternate paper code  
  • C.Y. Wu, J. Chen, Y.-S. Cheng, K.T. Hsu, K.H. Hu, C.Y. Liao
    NSRRC, Hsinchu, Taiwan
  Insertion devices (ID) are essential components in third-generation synchrotron light sources, which can produce highly-brilliant, collimated and quasi-monochromatic radiation over a broad energy range for experiments. Reliable operation of the insertion devices is important to users of beamlines. The most unpredictable fault is due to a soft error in optical absolute encoders due to radiation. There are several solutions to avoid such faults, e.g. by increasing the distance of the encoder from the beam, by a lead shield cover and finally by adopting an auxiliary position sensing devices to help recovery from a fault. Efforts to improve operational reliability of the TPS ID controls will be discussed.  
THP07 Long-term Stability Observed by Electron BPM and Photon BPM for Taiwan Photon Source -1
THPI7   use link to see paper's listing under its alternate paper code  
  • P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Huang
    NSRRC, Hsinchu, Taiwan
  TPS is 3-GeV synchrotron light source which have opened for public users since September 2016 and now offers 400 mA top-up mode operation. The requirements of the long term orbit stability and orbit reproducibility after beam trip have been gradually more and more stringent and become a challenge from users' request. Furthermore, the thermal effect would be expected to be worsen after 500 mA top-up operation which should deteriorate the orbit drift. The report investigates the long-term orbit stability observed from eBPM and XBPM and also evaluates the possibility of the local XBPM feedback.  
THP08 Design and Implementation of Stepper Motor Control of the LINAC High Power RF System Based on FPGA -1
THPI8   use link to see paper's listing under its alternate paper code  
  • R. Rujanakraikarn, Ch. Dhammatong, W. Phacheerak
    SLRI, Nakhon Ratchasima, Thailand
  In this paper, the new motion control system that governs the position of high power attenuators and phase shifters in the linac's RF system at SLRI is described. The drive system, which was originally driven by a set of AC reversible motors, is replaced by a new set of stepper motors. The hardware selection and installation is presented in detail. The digital control circuits are designed in VHDL and implemented on a commercial Field Programmable Gate Array (FPGA) board. The main software part, implemented in MicroBlaze Microcontroller System (MCS), is coded in C to control the position of stepper motors relative to the DC voltage reference points of the hardware system. A LabVIEW GUI is designed to interface with the control system to provide reference points and display position values via RS-232 and PLC interfaces. This stepper motor control system can be used to effectively implement the phase and amplitude control system of the linac's RF signals in the future.  
poster icon Poster THP08 [3.737 MB]  
THP10 Collimator Motion Control System Upgrade for Medical Linear Accelerator Project at SLRI -1
  • R. Rujanakraikarn, P. Koonpong, S. Tesprasitte
    SLRI, Nakhon Ratchasima, Thailand
  A prototype of the 6-MeV medical linear accelerator has been under development at Synchrotron Light Research Institute (SLRI). A set of secondary collimators is utilized with different size arrangement for beam shaping purpose. To produce the desired field size of the beam, the FPGA-based collimator motion control is designed in VHDL for simultaneous control of the collimators while the main PI control is implemented in the FPGA's main processor. In this paper, hardware and software upgrades of the collimator motion control system are presented. A custom drive hardware for individual collimator is designed to implement with the existing FPGA controller board. Interface between the custom hardware parts and the FPGA's programmable logic (PL) part is described. Communication between the motion control subsystem and the main LabVIEW control software on PC is modified to send and receive parameters wirelessly. Software modification of the FPGA's main processor part and that of the LabVIEW GUI part is also reported.  
poster icon Poster THP10 [3.859 MB]  
Development of Differential Currents Measurement System for MPS  
  • W. Wei, K. Gu
    IMP/CAS, Lanzhou, People's Republic of China
  To ensure safe and stable operation under high power beams, the accelerator device needs a fast, safe and reliable Machine Protection System (MPS). The MPS system uses the detector signals and sampled signals related to the beam quality to reflect the beam and machine status in real time, as well as to carry out chain protection to avoid critical equipment damage by the high power beams. This article mainly describes a differential currents measurement system, which monitors the beam current changes along the beam pipe and utilizes this distinct signal as a fast interlock protection output. The system obtains the signals of the beam current detectors online. By performing a fast average difference compensation calculation in FPGA, it can give a real-time stream strength and transmission efficiency of the beam. Then after setting a reasonable threshold, the system can give the fast interlock protection signal by evaluating the beam loss situation and provide an alternative solution of the low-energy beam loss issue in high-power accelerators.  
THP12 Upgrading the Synchronisation and Trigger Systems on the Vulcan High-Power Nd:glass Laser -1
THPI1   use link to see paper's listing under its alternate paper code  
  • D.A. Pepler, I. O. Musgrave, P.B.M. Oliveira
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  The Vulcan Neodymium-Glass High-Power Laser Facility at the Central Laser Facility in the UK has been operational for over 40 years providing a world-leading and high-profile service to International researchers in the field of Plasma Physics. Over that time the Facility has had many modifications and enhancements to the buildings, the laser hardware and to the computerised control, synchronisation and timing systems. As the laser systems have developed and the user experiments have continued to become much more complex and demanding, many new operational conditions have been required. The use of four independent laser oscillators with different properties - including temporal, spectral and operating frequencies - have meant that the optical and electrical multiplexing and the timing and synchronisation systems have all had to be adapted and extended to cope with these additional needs. However, these changes have resulted in the build-up of the overall system jitter to ± 250 ps between long (ns) and short (ps) optical pulses and this is a limiting factor for time-critical experiments. This paper will present some of the key changes and improvements that have recently been made.  
THP13 The Development of a FPGA Based Front End Safety Interlock System -1
  • J.-Y. Chuang, C.-C. Chang, C.M. Cheng, Y.Z. Lin, I.C. Sheng, Y.C. Yang
    NSRRC, Hsinchu, Taiwan
  A front end (FE) safety interlock control system was designed to protect humans and the machine integrity during operation. Since stability and reliability are an important requirement in this system, we developed a FPGA based system to control a safety logic for interlock protection. The integration of the FPGA, Real-time and redundant fail-safe system in the FE interlock system enables us to provide a safe protection with EPICS com-munication and hardware protection functions.  
Development of the New Spill Control Device for J-PARC MR  
  • T. Kimura
    KEK, Ibaraki, Japan
  J-PARC Main Ring (MR) is there are two operation modes of the fast extraction (FX) and slow extraction (SX). The SX operation used the spill control system. It consists of two kinds of Extraction Quadrupole Magnet (EQ), Ripple Quadrupole Magnet (RQ) and Spill Control Device with Digital Signal Processor (DSP) which calculates and controls it the optimal current pattern using the monitor signal of an extraction beam. It is used to make flatten the extraction beam structure and reduce the ripple noise. The present Spill Control Device needs to be reviewed from the aspect of service life etc. In this presentation, we will focus on improving the versatility of the device and the operability of the DSP program, and explain the development of the next-generation spill control device.  
THP15 Design and Implementation of FPGA Based Protection System for Beam Acceleration in Linear IFMIF Prototype Accelerator -1
  • Y. Hirata, A. Kasugai
    QST, Aomori, Japan
  • A. Jokinen, A. Marqueta
    Fusion for Energy, Garching, Germany
  • H. Takahashi
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  IFMIF (International Fusion Materials Irradiation Facility) Prototype Accelerator (LIPAc) has been developed, which is designed to produce a deuteron CW beam with a current of 125 mA at 9 MeV. After the injector commissioning, the LIPAc is entering in the second commissioning phase in which RFQ, MEBT, RF Power System and Beam Instrumentation (BI) systems have been integrated. The LCSs of LIPAc have been developed by European Home Team (EU-HT) and delivered with its subsystems; the CCS, including personnel and machine protection, timing, archiving and alarming, by Japanese Home Team (JA-HT). These have been implemented on the EPICS platform to mitigate the risk of incompatibility in the integration, which JA-HT and EU-HT are jointly carrying out to control the whole accelerator. In the CCS, some interlocks associated with measurement systems–chopper interlock, protection of BI systems, etc.–are implemented on FPGA and the condition of interlock triggering can be changed from EPICS OPIs depending on the beam conditions. The use of EPICS interface can add flexibility but still satisfy fast response and reliability requirement. The design and implementation will be presented.  
THP16 Remote Waveform Access Supports with EPICS for TPS and TLS Control Systems -1
  • Y.-S. Cheng, K.T. Hsu, K.H. Hu, C.Y. Liao, C.Y. Wu
    NSRRC, Hsinchu, Taiwan
  To eliminate long distance cabling for improving signal quality, the remote waveform access supports have been developed and applied on the TPS (Taiwan Photon Source) and TLS (Taiwan Light Source) control systems. Waveforms include pulse magnets power supplies waveforms, AC waveforms of main power supplies, LLRF waveforms, beam signals, etc., and these are necessary to be monitored during routine beam operation. One is that use the EPICS-embedded data acquisition systems which are formed by the Zynq System-on-Chip architecture to capture the waveform signals; the other is that a dedicated EPICS IOC is used to communicate with the present Ethernet-based oscilloscopes to acquire each waveform data. According to specific purposes use, the different graphical applications have been developed and integrated into the existing operation interfaces. These are convenient to observe waveform status and to analyze the acquired data on the control consoles. The efforts are described at this paper.  
poster icon Poster THP16 [0.731 MB]  
THP17 Injection and Extraction Timing Controls at SuperKEKB Damping Ring -1
  • H. Sugimura, H. Kaji, F. Miyahara, S. Sasaki, M. Satoh
    KEK, Ibaraki, Japan
  • Y. Iitsuka
    EJIT, Hitachi, Ibaraki, Japan
  • T. Kudou, S. Kusano
    Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan
  SuperKEKB project aims at world highest luminosity to 8x1035cm-2s-1. To achieve the luminosity, a lot of equipment was newly constructed or upgraded. Especially, Damping Ring (DR) was newly constructed for reducing positron emittance, and was located at the middle of the injector LINAC. The DR timing system was also constructed. The synchronized timing which is generated at injector LINAC, is received at DR sub timing station and is distributed the end of some equipment, Kicker, Septum, and monitoring devices. We succeeded to generate not only synchronized timing but also beam control information such as beam gate for trigger inhibit signal and injection and extraction timing "value" via data buffer delivery. By using this method, accelerator operation became more convenient system.  
THP18 Operational Experience of the Digital LLRF Control System at the Booster Ring of Taiwan Photon Source -1
  • Z.K. Liu, F.Y. Chang, L.-H. Chang, M.H. Chang, S.W. Chang, L.J. Chen, F.-T. Chung, Y.D. Li, M.-C. Lin, C.H. Lo, Ch. Wang, M.-S. Yeh, T.-C. Yu
    NSRRC, Hsinchu, Taiwan
  The purpose of a Low-Level Radio Frequency (LLRF) system is to control the accelerating cavity field amplitude and phase. To have better RF field stability, precise control and high noise reduction, a digital LLRF control system based on Field Programmable Gate Arrays (FPGA) was developed at NSRRC. We replaced the analog LLRF system with a digital version for the TPS booster ring at the beginning of 2018. During routine operation of the booster RF, some faults occurred when the digital LLRF operated in the energy savings mode. The performance and operational experience of the digital LLRF for the TPS booster will be presented here.  
THP19 Timing System for Multiple Accelerator Rings at KEK e+/e Injector LINAC -1
  • F. Miyahara, K. Furukawa, H. Kaji, M. Satoh, H. Sugimura
    KEK, Ibaraki, Japan
  • T. Kudo, S. Kusano
    Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan
  • H.S. Saotome
    Kanto Information Service (KIS), Accelerator Group, Ibaraki, Japan
  The KEK e+/e injector linac is operated in multiple modes that can be switched every 20 ms for e+/e beam injection to five different accelerator rings, SuperKEKB High Energy Ring (HER), Photon Factory (PF) ring, PF-AR, positron damping ring (DR) and SuperKEKB Low Energy Ring (LER). The MRF event system which consists of event generators (EVG) and event receivers (EVR) is used to distribute event codes that correspond to beam modes and data buffer. The EVR generates various trigger timing signals depending on the event code. The data buffer incudes some important parameters such as HER/PDR injection RF bucket, setting currents of pulsed quad/steering magnets that enables multiple beam injection. The event system uses the linac main clock (114.2 MHz) which synchronized to HER/LER, but due to PF and PF-AR rings are not synchronized to the linac, an additional synchronization system is employed for those rings. We will describe the timing and synchronization system to fulfill multiple injections to independent rings and report status of the system.  
THP20 Study of Energy Saving Operation for the TLS Booster Power Supply -1
  • J. Chen, Y.-S. Cheng, K.T. Hsu, K.H. Hu, D. Lee, C.Y. Liao, C.Y. Wu
    NSRRC, Hsinchu, Taiwan
  Operating an injector of a synchrotron light source, energy efficiency is an important issue. Dipole and quadrupoles families of the booster synchrotron for Taiwan Light Source (TLS) is resonantly excited by three White circuits at 10 Hz rate. Magnet current cannot response in cycle-by-cycle basic due to resonance nature. The possibility of operation of the booster synchrotron in energy saving mode is explored. Minimizing the duration of magnet excitation without effect of the injected and extracted beam to support top-up operation for the TLS is investigated. Efforts will be presented in this report.  
Development of Triggered Scaler to Detect Miss-Trigger  
  • N. Kamikubota
    KEK, Ibaraki, Japan
  • K.C. Sato
    J-PARC, KEK & JAEA, Ibaraki-ken, Japan
  • Y. Tajima
    KIS, Ibaraki, Japan
  • S.Y. Yoshida
    Kanto Information Service (KIS), Accelerator Group, Ibaraki, Japan
  A "triggered scaler" has been developed for J-PARC accelerators. It is a PLC-type scaler with a memory array. Number of pulsed signals is counted and stored in a cell of memory array, then, each external trigger (typically 25Hz) shifts the pointer to the cell. The memory size (maximum 192) is designed to store one machine-cycle (2.48s or 5.20s in J-PARC). Stored data (converted to an EPICS waveform PV) is analyzed every machine cycle, to verify no miss-trigger (or to detect a miss-trigger) in the previous machine cycle. Using a prototype of triggered scaler, two demonstrative measurements are given: (a) Frequency modulation (injection - ramp-up - extraction) of a RF signal was measured. The measured data is used to evaluate rough machine energies. (b) MPS events were detected by a triggered scaler. Visualizing observed data is effective to notify operators which phase a MPS event occurred in a machine cycle. Based on these measurements, a plan to detect a miss-trigger will be discussed.  
THP22 Guaranteeing the Measurement Accuracy in Em#* -1
  • X. Serra-Gallifa, J.A. Avila-Abellan, M. Broseta, G. Cuní, O. Matilla
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
  ALBA, in collaboration with MAXIV, has developed a four-channel electrometer of 18bit deep with 8 ranges from 1mA to 100pA. The objective of accuracy in the measurements made clear from the beginning the need to compensate the components tolerances and its dependence with temperature. This paper describes the tests performed to characterize the acquisition chain, the automatic calibration developed and the hardware and software implemented to achieve the accuracy target. This implementation has been eased due to the high flexibility given by ALIN and Harmony** architectures used in the Em#.
* J.Avila-Abellan, "Em# Electrometer Comes to Light", ICALEPCS'17.
** M.Broseta, "Present and Future of Harmony Bus, a real-time high speed bus for data transfer between FPGA cores", ICALEPCS'17.
poster icon Poster THP22 [1.038 MB]  
THP23 Further Improvements in Power Supply Controller Transient Recorders for Post-Mortem Analysis of BPM Orbit Dumps at PETRA-III -1
  • P.K. Bartkiewicz, C. Gindler, G.K. Sahoopresenter
    DESY, Hamburg, Germany
  PETRA-III is a 3rd generation synchrotron light source dedicated to users with 14 beamlines beginning operations in 2010. The storage ring was modified in 2014 for an additional 12 beamlines in two extensions. It is operated with several filling modes with 100mA at electron beam energy of 6 GeV. The horizontal beam emittance is 1.30 nmrad with 1% coupling. During a user run the Machine Protection System may trigger an unscheduled beam dump if transients in the magnet power supply (PS) currents are detected which are above permissible limits. PS controllers provide transient recorder data, showing differences between current set-point and readout values in a time span of several seconds around the moment of a beam loss. We describe automatic management system handling a large number of PSs, performing automatic transient recorder data readout, storing and available for offline analysis. We discuss hardware implementation of transient recorders and its configuration software, a Java GUI application used to investigate the transient behavior of different PSs, which might have been responsible for emittance growth, orbit fluctuations, or the beam dumps seen in a post-mortem analysis.  
poster icon Poster THP23 [1.904 MB]