ICALEPCS2013 - List of Keywords (LLRF)

Paper	Title	Other Keywords	Page
MOCOBAB02	Integration of PLC with EPICS IOC for SuperKEKB Control System	controls, PLC, EPICS, interface	31
	J.-I. Odagiri, K. Furukawa, T.T. Nakamura KEK, Ibaraki, Japan
	Recently, more and more PLCs are adopted for various frontend controls of　accelerators. It is common to connect the PLCs with higher level control layers by the network. As a result, control logic becomes dispersed over separate layers, one of which is implemented by ladder programs on PLCs, and the other is implemented by higher level languages on frontend computers. EPICS-based SuperKEKB accelerator control system, however, take a different approach by using FA-M3 PLCs with a special CPU module (F3RP61), which runs Linux and functions as an IOC. This consolidation of PLC and IOC enables higher level applications to directly reach every PLC placed at frontends by Channel Access. In addition, most of control logic can be implemented by the IOC core program and/or EPICS sequencer to make the system more homogeneous resulting in easier development and maintenance of applications. This type of PLC-based IOCs are to be used to monitor and control many subsystems of SuperKEKB, such as personnel protection system, vacuum system, RF system, magnet power supplies, and so on. This paper describes the applications of the PLC-based IOCs to the SuperKEKB accelerator control system.
	Slides MOCOBAB02 [1.850 MB]

TUCOCA09	Klystron Measurement and Protection System for XFEL on the MTCA.4 Architecture	klystron, high-voltage, vacuum, FPGA	937
	Ł. Butkowski, H. Schlarb, V. Vogel DESY, Hamburg, Germany
	The European XFEL free-electron laser is under construction at the DESY. The driving engine of the superconducting accelerator will be 27 RF station. Each of an underground RF station consist from multi beam horizontal klystron which can provide up to 10MW of power at 1.3GHz. The XFEL should work continuously over 20 years with only 1 day per month for maintenance. In order to meet so demanding requirement lifetime of the MBK should be as long as possible. In the real operation the lifetime of tube can be thoroughly reduced by service conditions. To minimize the influence of service conditions to the klystrons lifetime the special fast protection system named as Klystron Lifetime Management System (KLM) has been developed, the main task of this system is to detect all events which can destroy the tube as quickly as possible, and then stop input power to the tube and send signal to stop HV pulse. The tube recovery procedure should depend on the kind of events has happened. KLM is based on the standard LLRF uTCA system for XFEL with additional DC channels. This article gives an overview of implementation of measurement and protection system installed at klystron test stand.
	Slides TUCOCA09 [0.496 MB]

THPPC072	Superconducting Cavity Quench Detection and Prevention for the European XFEL	cavity, operation, cryogenics, coupling	1239
	J. Branlard, V. Ayvazyan, O. Hensler, H. Schlarb, Ch. Schmidt DESY, Hamburg, Germany W. Cichalewski TUL-DMCS, Łódź, Poland
	Due to its large scale, the European X-ray Free Electron Laser accelerator (XFEL) requires a high level of automation for commissioning and operation. Each of the 800 superconducting RF cavities simultaneously running during normal operation can occasionally quench, potentially tripping the cryogenic system and resulting into machine down-time. A fast and reliable quench detection system is then a necessity to rapidly detect individual cavity quenches and take immediate action, thus avoiding interruption of machine operation. In this paper, the mechanisms implemented in the low level RF system (LLRF) to prevent quenches and the algorithms developed to detect if a cavity quenches anyways are explained. In particular, the different types of cavity quenches and the techniques developed to identify them are shown. Experimental results acquired during the testing of XFEL cryomodules prototypes at DESY are presented, demonstrating the performance and efficiency of this machine operation and cavity protection tool.

THPPC122	High Performance and Low Latency Single Cavity RF Control Based on MTCA.4	controls, feedback, cavity, hardware	1348
	Ch. Schmidt, L. Butkowski, M. Hoffmann, H. Schlarb DESY, Hamburg, Germany M. Grzegrzółka, I. Rutkowski Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
	The European XFEL project at DESY requires a very precise RF control, fulfilling the objectives of high performance FEL generation. Within the MTCA.4 based hardware framework a LLRF system has been designed to control multi-cavity applications, require large processing capabilities. A generic software structure allows to apply the same design also for single-cavity applications, reducing efforts for maintenance. It has be demonstrated that the MTCA.4 based LLRF controller development achieves XFEL requirement in terms of amplitude and phase control. Due to the complexity of the signal part, which is not essential for a single cavity regulation an alternative framework has been developed, to minimize processing latency which is especially for high bandwidth applications very important. This setup is based on a fast processing advanced mezzanine card (AMC) combined with a down-converter and vector-modulator rear transition module (RTM). Within this paper the system layout and first measurement results are presented, demonstrating capabilities not only for LLRF specific applications.

THPPC135	From Pulse to Continuous Wave Operation of TESLA Cryomodules – LLRF System Software Modification and Development	operation, feedback, cavity, controls	1366
	W. Cichalewski, W. Jałmużna, A. Piotrowski, K.P. Przygoda TUL-DMCS, Łódź, Poland V. Ayvazyan, J. Branlard, H. Schlarb, J.K. Sekutowicz DESY, Hamburg, Germany J. Szewiński NCBJ, Świerk/Otwock, Poland
	Funding: We acknowledge the support from National Science Center (Poland) grant no 5593/B/T02/2010/39 Higher efficiency of TESLA based free electron lasers (FLASH, XFEL) by means of increased quantity of photon bursts can be achieved using continuous wave operation mode. In order to maintain constant beam acceleration in superconducting cavities and keep short pulse to CW operation transition costs reasonably low some substantial modification of accelerator subsystems are necessary. Changes in: RF power source, cryo systems, electron beam source, etc. have to be also accompanied by adjustments in LLRF system. In this paper challenges for well established pulsed mode LLRF system are discussed (in case of CW and LP scenarios). Firmware, software modifications needed for maintaining high performance of cavities field parameters regulation (for 1Hz CW and LP cryo-module operation) are described. Results from studies of vector sum amplitude and phase control in case of resonators high Ql factor settings (Ql~1.5e7) are shown. Proposed modifications implemented in VME and microTCA (MTCA.4) based LLRF system has been tested during studies at CryoModule Test Bench (CMTB) in DESY. Results from this tests together with achieved regulation performance data are also presented and discussed.
	Poster THPPC135 [1.310 MB]

THPPC140	MTCA Upgrade of the Readout Electronics for the Bunch Arrival Time Monitor at FLASH	laser, electronics, feedback, electron	1380
	J. Szewiński, G. Boltruczyk, S. Korolczuk NCBJ, Świerk/Otwock, Poland S. Bou Habib, J. Dobosz, D. Sikora Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland C. Gerth, H. Schlarb DESY, Hamburg, Germany
	Bunch Arrival time Monitor (BAM) is an electro-optical device used at FLASH accelerator in DESY for the high precision, femtosecond scale, measurements of the moment when electron bunch arrives at the reference point in the machine. The arrival time is proportional to the average bunch energy, and is used to calculate the amplitude correction for RF field control. Correction is sent to the LLRF system in less than 10 us, and this creates a secondary feedback loop (over the regular LLRF one), which is focused on beam energy stabilization - beam feedback. This paper presents new uTCA BAM readout electronics design based on the uTCA.4 – “uTCA for Physics” and FMC mezzanine boards standards. Presented solution is a replacement for existing, VME based BAM readout devices. It provides higher efficiency by using new measurement techniques, better components (such as ADCs, FPGAs etc.), and high bandwidth uTCA backplane. uTCA provides also different topology for data transfers in the crate, which all together opens new opportunities for the improvement of the overall system performance.
	Poster THPPC140 [14.281 MB]

FRCOBAB05	Distributed Feedback Loop Implementation in the RHIC Low Level RF Platform	cavity, controls, damping, FPGA	1501
	F. Severino, M. Harvey, T. Hayes, G. Narayan, K.S. Smith BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DEAC02-98CH10886 with the U.S. Department of Energy. We present a brief overview of distributed feedback systems based on the RHIC LLRF Platform. The general architecture and sub-system components of a complex feedback system are described, emphasizing the techniques and features employed to achieve deterministic and low latency data and timing delivery between local and remote sub-systems: processors, FPGA fabric components and the high level control system. In particular, we will describe how we make use of the platform to implement a widely distributed multi-processor and FPGA based longitudinal damping system, which relies on task sharing, tight synchronization and integration to achieve the desired functionality and performance.
	Slides FRCOBAB05 [3.147 MB]

Paper

Title

Other Keywords

Page

MOCOBAB02

Integration of PLC with EPICS IOC for SuperKEKB Control System

controls, PLC, EPICS, interface

31

J.-I. Odagiri, K. Furukawa, T.T. Nakamura
KEK, Ibaraki, Japan

Recently, more and more PLCs are adopted for various frontend controls of　accelerators. It is common to connect the PLCs with higher level control layers by the network. As a result, control logic becomes dispersed over separate layers, one of which is implemented by ladder programs on PLCs, and the other is implemented by higher level languages on frontend computers. EPICS-based SuperKEKB accelerator control system, however, take a different approach by using FA-M3 PLCs with a special CPU module (F3RP61), which runs Linux and functions as an IOC. This consolidation of PLC and IOC enables higher level applications to directly reach every PLC placed at frontends by Channel Access. In addition, most of control logic can be implemented by the IOC core program and/or EPICS sequencer to make the system more homogeneous resulting in easier development and maintenance of applications. This type of PLC-based IOCs are to be used to monitor and control many subsystems of SuperKEKB, such as personnel protection system, vacuum system, RF system, magnet power supplies, and so on. This paper describes the applications of the PLC-based IOCs to the SuperKEKB accelerator control system.

Slides MOCOBAB02 [1.850 MB]

TUCOCA09

Klystron Measurement and Protection System for XFEL on the MTCA.4 Architecture

klystron, high-voltage, vacuum, FPGA

937

Ł. Butkowski, H. Schlarb, V. Vogel
DESY, Hamburg, Germany

The European XFEL free-electron laser is under construction at the DESY. The driving engine of the superconducting accelerator will be 27 RF station. Each of an underground RF station consist from multi beam horizontal klystron which can provide up to 10MW of power at 1.3GHz. The XFEL should work continuously over 20 years with only 1 day per month for maintenance. In order to meet so demanding requirement lifetime of the MBK should be as long as possible. In the real operation the lifetime of tube can be thoroughly reduced by service conditions. To minimize the influence of service conditions to the klystrons lifetime the special fast protection system named as Klystron Lifetime Management System (KLM) has been developed, the main task of this system is to detect all events which can destroy the tube as quickly as possible, and then stop input power to the tube and send signal to stop HV pulse. The tube recovery procedure should depend on the kind of events has happened. KLM is based on the standard LLRF uTCA system for XFEL with additional DC channels. This article gives an overview of implementation of measurement and protection system installed at klystron test stand.

Slides TUCOCA09 [0.496 MB]

THPPC072

Superconducting Cavity Quench Detection and Prevention for the European XFEL

cavity, operation, cryogenics, coupling

1239

J. Branlard, V. Ayvazyan, O. Hensler, H. Schlarb, Ch. Schmidt
DESY, Hamburg, Germany
W. Cichalewski
TUL-DMCS, Łódź, Poland

Due to its large scale, the European X-ray Free Electron Laser accelerator (XFEL) requires a high level of automation for commissioning and operation. Each of the 800 superconducting RF cavities simultaneously running during normal operation can occasionally quench, potentially tripping the cryogenic system and resulting into machine down-time. A fast and reliable quench detection system is then a necessity to rapidly detect individual cavity quenches and take immediate action, thus avoiding interruption of machine operation. In this paper, the mechanisms implemented in the low level RF system (LLRF) to prevent quenches and the algorithms developed to detect if a cavity quenches anyways are explained. In particular, the different types of cavity quenches and the techniques developed to identify them are shown. Experimental results acquired during the testing of XFEL cryomodules prototypes at DESY are presented, demonstrating the performance and efficiency of this machine operation and cavity protection tool.

THPPC122

High Performance and Low Latency Single Cavity RF Control Based on MTCA.4

controls, feedback, cavity, hardware

1348

Ch. Schmidt, L. Butkowski, M. Hoffmann, H. Schlarb
DESY, Hamburg, Germany
M. Grzegrzółka, I. Rutkowski
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland

The European XFEL project at DESY requires a very precise RF control, fulfilling the objectives of high performance FEL generation. Within the MTCA.4 based hardware framework a LLRF system has been designed to control multi-cavity applications, require large processing capabilities. A generic software structure allows to apply the same design also for single-cavity applications, reducing efforts for maintenance. It has be demonstrated that the MTCA.4 based LLRF controller development achieves XFEL requirement in terms of amplitude and phase control. Due to the complexity of the signal part, which is not essential for a single cavity regulation an alternative framework has been developed, to minimize processing latency which is especially for high bandwidth applications very important. This setup is based on a fast processing advanced mezzanine card (AMC) combined with a down-converter and vector-modulator rear transition module (RTM). Within this paper the system layout and first measurement results are presented, demonstrating capabilities not only for LLRF specific applications.

THPPC135

From Pulse to Continuous Wave Operation of TESLA Cryomodules – LLRF System Software Modification and Development

operation, feedback, cavity, controls

1366

W. Cichalewski, W. Jałmużna, A. Piotrowski, K.P. Przygoda
TUL-DMCS, Łódź, Poland
V. Ayvazyan, J. Branlard, H. Schlarb, J.K. Sekutowicz
DESY, Hamburg, Germany
J. Szewiński
NCBJ, Świerk/Otwock, Poland

Funding: We acknowledge the support from National Science Center (Poland) grant no 5593/B/T02/2010/39
Higher efficiency of TESLA based free electron lasers (FLASH, XFEL) by means of increased quantity of photon bursts can be achieved using continuous wave operation mode. In order to maintain constant beam acceleration in superconducting cavities and keep short pulse to CW operation transition costs reasonably low some substantial modification of accelerator subsystems are necessary. Changes in: RF power source, cryo systems, electron beam source, etc. have to be also accompanied by adjustments in LLRF system. In this paper challenges for well established pulsed mode LLRF system are discussed (in case of CW and LP scenarios). Firmware, software modifications needed for maintaining high performance of cavities field parameters regulation (for 1Hz CW and LP cryo-module operation) are described. Results from studies of vector sum amplitude and phase control in case of resonators high Ql factor settings (Ql~1.5e7) are shown. Proposed modifications implemented in VME and microTCA (MTCA.4) based LLRF system has been tested during studies at CryoModule Test Bench (CMTB) in DESY. Results from this tests together with achieved regulation performance data are also presented and discussed.

Poster THPPC135 [1.310 MB]

THPPC140

MTCA Upgrade of the Readout Electronics for the Bunch Arrival Time Monitor at FLASH

laser, electronics, feedback, electron

1380

J. Szewiński, G. Boltruczyk, S. Korolczuk
NCBJ, Świerk/Otwock, Poland
S. Bou Habib, J. Dobosz, D. Sikora
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
C. Gerth, H. Schlarb
DESY, Hamburg, Germany

Bunch Arrival time Monitor (BAM) is an electro-optical device used at FLASH accelerator in DESY for the high precision, femtosecond scale, measurements of the moment when electron bunch arrives at the reference point in the machine. The arrival time is proportional to the average bunch energy, and is used to calculate the amplitude correction for RF field control. Correction is sent to the LLRF system in less than 10 us, and this creates a secondary feedback loop (over the regular LLRF one), which is focused on beam energy stabilization - beam feedback. This paper presents new uTCA BAM readout electronics design based on the uTCA.4 – “uTCA for Physics” and FMC mezzanine boards standards. Presented solution is a replacement for existing, VME based BAM readout devices. It provides higher efficiency by using new measurement techniques, better components (such as ADCs, FPGAs etc.), and high bandwidth uTCA backplane. uTCA provides also different topology for data transfers in the crate, which all together opens new opportunities for the improvement of the overall system performance.

Poster THPPC140 [14.281 MB]

FRCOBAB05

Distributed Feedback Loop Implementation in the RHIC Low Level RF Platform

cavity, controls, damping, FPGA

1501

F. Severino, M. Harvey, T. Hayes, G. Narayan, K.S. Smith
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DEAC02-98CH10886 with the U.S. Department of Energy.
We present a brief overview of distributed feedback systems based on the RHIC LLRF Platform. The general architecture and sub-system components of a complex feedback system are described, emphasizing the techniques and features employed to achieve deterministic and low latency data and timing delivery between local and remote sub-systems: processors, FPGA fabric components and the high level control system. In particular, we will describe how we make use of the platform to implement a widely distributed multi-processor and FPGA based longitudinal damping system, which relies on task sharing, tight synchronization and integration to achieve the desired functionality and performance.

Slides FRCOBAB05 [3.147 MB]