PCaPAC2012 - List of Keywords (feedback)

Paper	Title	Other Keywords	Page
THPD05	Design and Analysis of Second Harmonics Modulator for DC Current Transformer	pick-up, controls, instrumentation, factory	145
	K.D. Joshi, K. Reju BARC, Mumbai, India
	DC Current Transformers (DCCT) are widely used in the world of particle accelerators. DCCT is a device which produces even harmonics, predominantly second harmonics corresponding to DC beam current flowing through two toroids. The second harmonics is detected by digital synchronous detector implemented in programmable logic. Current proportional to the detected second harmonic is passed through the toroids in a feedback loop such that the flux due to the DC beam current is cancelled by it. This feedback current is the measure of average beam current. The high permeability toroids, excitation and output windings are collectively called magnetic modulator, which is a key component of DCCT. Design and analysis of a second-harmonic magnetic modulator used as a detector for DC Current transformer for high resolution current measurement is presented.
	Poster THPD05 [0.498 MB]

THPD16	Fast Digital Feedback Control Systems for Accelerator RF System using FPGA	controls, LLRF, low-level-rf, cavity	172
	P.S. Bagduwal, P.R. Hannurkar, M. Lad, D. Sharma, N. Tiwari RRCAT, Indore (M.P.), India
	Funding: RRCAT Indore Feedback control system plays important role for proper injection and acceleration of beam in particle accelerators by providing the required amplitude and phase stability of RF fields in accelerating structures. Advanced digital technologies allow development of control systems for RF applications. Digital LLRF system offers inherent advantages like flexibility, adaptability, good repeatability and low drift errors compared to analog system. For feedback control algorithm, I/Q control scheme is used. Properly sampling of down converted IF generates accurate feedback signal and eliminates the need of separate detector for amplitude and phase. Controller is implemented in Vertex-4 FPGA with proper control algorithm which offers fast correction with good accuracy and also controls the amplitude and phase in all four quadrants. Single I/Q modulator work as common correctors for both amplitude and phase. LO signal is derived from RF signal itself to achieve synchronization between RF, LO and FPGA clock. Control system has been successfully tested in laboratory with phase and amplitude stability better then ± 1% and ±1°. With minor modification same systems can be used at any frequencies.

THPD18	Adaptive Fuzzy Control for Transfer Channels in Particle Accelerators	controls, fuzzy set, synchrotron, positron	178
	S. Berlik University of Siegen, Siegen, Germany H. Ehrlichmann DESY, Hamburg, Germany
	Funding: DESY, Germany Long-term objective of this work is to develop a fuzzy technology based control framework to be applied in particle accelerators. Main motivation for this is the promise of fuzzy systems to exploit the tolerance for imprecision, un-certainty, and partial truth to achieve tractability, robustness, and low solution cost. Intended areas of application are manifold: we think on automatic operation, optimization of the operating conditions and yields; applied to various stages in the processing of circular and linear accelerators. As a first step towards this goal a fuzzy control system for a transfer channel in a particle accelerator has been developed. For it we built up the machinery, i.e. algorithms, data structures, integration in the existing control system and did a first proof-of-concept. Special emphasis is given on handling high dimensional data streams and the immanent challenges as sparsity and equidistance of the data.
	Poster THPD18 [0.569 MB]

THPD19	Drive System Control for Kolkata Superconducting Cyclotron Extraction System	extraction, controls, cyclotron, high-voltage	181
	T. Bhattacharyya, S. Bhattacharya, T. Das, C. Nandi, G.P. Pal VECC, Kolkata, India
	The K500 Superconducting Cyclotron at VECC, Kolkata uses two electrostatic deflectors, eight passive magnetic channels, one active magnetic channel and two compensating bars as its extraction elements. Except the active magnetic channel, all the other elements can be moved radially, typically by ±6 mm around a centre position. This maneuverability is due to the fact that not all the ions, spanning the operating region of the cyclotron, will have the same optimum beam extraction radius. At the end of the beam extraction channel, the beam is shaped and aligned by a pair of water cooled slit. The slit movement is pneumatically controlled as it has to be operated in high magnetic field. The computer controlled drive system can move the elements precisely. The paper will describe the drive system and its control mechanism.
	Poster THPD19 [0.933 MB]

THPD20	RF Distribution and Control System for Accelerators of the VEC-RIB Facility	controls, LLRF, cavity, low-level-rf	184
	H.K. Pandey, S. Basak, D.P. Dutta, T.K. Mandi VECC, Kolkata, India A. Kumar, K. P. Ray SAMEER, Kolkata, India
	RIB facility at VECC has several heavy ion linear accelerators like RFQ, two IH-LNACs and one buncher cavity operating at 37.8 MHz and two IH-LINACs with one buncher cavity at 75.6 MHz. Some more RF cavities are being designed at the third harmonic of 37.8 MHz and will be added in the RIB beam line. All the cavities have separate RF power amplifiers with proper amplitude, phase and resonance frequency tuning and control system for efficient and stable operation. The LLRF control system has been operational for the power amplifiers of the existing RF cavities and improved design and development is carried out. The main features of the RF control system are phase and amplitude control of the RF input to the amplifiers and tuning of the RF cavity to the desired resonant frequency with automation using feedback control. It will also have various interlocks for the safety of the load as well as the amplifier. A micro-controller based data acquisition and processing system is being used for control and local/remote operation. The RF distribution system as well as the design details of RF control system will be presented in this paper.
	Poster THPD20 [2.163 MB]

THPD35	Modeling and Simulation of Indus-2 RF Feedback Control System	cavity, simulation, controls, LLRF	208
	D. Sharma, P.S. Bagduwal, P.R. Hannurkar, M. Lad, N. Tiwari RRCAT, Indore (M.P.), India
	Funding: RRCAT, Indore, Department of Atomic Energy, Government of India The Indus-2 synchrotron radiation source has four RF stations along with their feedback control systems. For higher beam energy and current operation, amplitude and phase feedback control systems of Indus-2 are being upgraded. To understand the behavior of amplitude and phase control loop under different operating conditions, modeling and simulation of RF feedback control system is done. RF cavity base band quadrature domain model has been created due to its close correspondence with actual implementation and better computational efficiency which make the simulation faster. Correspondence between base band and actual RF cavity model is confirmed by comparing their simulation results. Base band Cavity model was studied under different operating conditions. LLRF feed back control system simulation is done using the same cavity model. Error signals are intentionally generated and response of the closed loops system is observed. With implementation of feedback control loop, broadening in the RF cavity bandwidth was also observed in terms of reduction in cavity fill time. Simulation will help us in optimizing parameters of upgraded LLRF system for higher beam energy and current operation.
	Poster THPD35 [0.698 MB]

FRID01	Introducing the !CHAOS Control Systems Framework	controls, GUI	282
	L. Catani, F. Zani INFN-Roma II, Roma, Italy C. Bisegni, D. Di Giovenale, G. Di Pirro, L.G. Foggetta, G. Mazzitelli, A. Stecchi INFN/LNF, Frascati (Roma), Italy
	The analysis of most recent developments on high-performance software technologies suggests that new a design of distributed control systems (DCS) for particle accelerators may profit from solutions borrowed from cutting-edge Internet services. To fully profit from this new technologies the DCS model should be reconsidered, thus leading to the definition of a new paradigm. In this paper we present the conceptual design of a new control system for a particle accelerator and associated machine data acquisition system (DAQ), based on a synergic combination of a non-relational key/value database (KVDB) and network distributed object caching (DOC). The use of these technologies, to implement continuous data archiving and data distribution between components respectively, brought about the definition of a new control system concept offering a number of interesting features such as a high level of abstraction of services and components and their integration in a framework that can be seen as a comprehensive control services provider for GUI applications, front-end controllers, measurement and feedback procedures etc.

Paper

Title

Other Keywords

Page

THPD05

Design and Analysis of Second Harmonics Modulator for DC Current Transformer

pick-up, controls, instrumentation, factory

145

K.D. Joshi, K. Reju
BARC, Mumbai, India

DC Current Transformers (DCCT) are widely used in the world of particle accelerators. DCCT is a device which produces even harmonics, predominantly second harmonics corresponding to DC beam current flowing through two toroids. The second harmonics is detected by digital synchronous detector implemented in programmable logic. Current proportional to the detected second harmonic is passed through the toroids in a feedback loop such that the flux due to the DC beam current is cancelled by it. This feedback current is the measure of average beam current. The high permeability toroids, excitation and output windings are collectively called magnetic modulator, which is a key component of DCCT. Design and analysis of a second-harmonic magnetic modulator used as a detector for DC Current transformer for high resolution current measurement is presented.

Poster THPD05 [0.498 MB]

THPD16

Fast Digital Feedback Control Systems for Accelerator RF System using FPGA

controls, LLRF, low-level-rf, cavity

172

P.S. Bagduwal, P.R. Hannurkar, M. Lad, D. Sharma, N. Tiwari
RRCAT, Indore (M.P.), India

Funding: RRCAT Indore
Feedback control system plays important role for proper injection and acceleration of beam in particle accelerators by providing the required amplitude and phase stability of RF fields in accelerating structures. Advanced digital technologies allow development of control systems for RF applications. Digital LLRF system offers inherent advantages like flexibility, adaptability, good repeatability and low drift errors compared to analog system. For feedback control algorithm, I/Q control scheme is used. Properly sampling of down converted IF generates accurate feedback signal and eliminates the need of separate detector for amplitude and phase. Controller is implemented in Vertex-4 FPGA with proper control algorithm which offers fast correction with good accuracy and also controls the amplitude and phase in all four quadrants. Single I/Q modulator work as common correctors for both amplitude and phase. LO signal is derived from RF signal itself to achieve synchronization between RF, LO and FPGA clock. Control system has been successfully tested in laboratory with phase and amplitude stability better then ± 1% and ±1°. With minor modification same systems can be used at any frequencies.

THPD18

Adaptive Fuzzy Control for Transfer Channels in Particle Accelerators

controls, fuzzy set, synchrotron, positron

178

S. Berlik
University of Siegen, Siegen, Germany
H. Ehrlichmann
DESY, Hamburg, Germany

Funding: DESY, Germany
Long-term objective of this work is to develop a fuzzy technology based control framework to be applied in particle accelerators. Main motivation for this is the promise of fuzzy systems to exploit the tolerance for imprecision, un-certainty, and partial truth to achieve tractability, robustness, and low solution cost. Intended areas of application are manifold: we think on automatic operation, optimization of the operating conditions and yields; applied to various stages in the processing of circular and linear accelerators. As a first step towards this goal a fuzzy control system for a transfer channel in a particle accelerator has been developed. For it we built up the machinery, i.e. algorithms, data structures, integration in the existing control system and did a first proof-of-concept. Special emphasis is given on handling high dimensional data streams and the immanent challenges as sparsity and equidistance of the data.

Poster THPD18 [0.569 MB]

THPD19

Drive System Control for Kolkata Superconducting Cyclotron Extraction System

extraction, controls, cyclotron, high-voltage

181

T. Bhattacharyya, S. Bhattacharya, T. Das, C. Nandi, G.P. Pal
VECC, Kolkata, India

The K500 Superconducting Cyclotron at VECC, Kolkata uses two electrostatic deflectors, eight passive magnetic channels, one active magnetic channel and two compensating bars as its extraction elements. Except the active magnetic channel, all the other elements can be moved radially, typically by ±6 mm around a centre position. This maneuverability is due to the fact that not all the ions, spanning the operating region of the cyclotron, will have the same optimum beam extraction radius. At the end of the beam extraction channel, the beam is shaped and aligned by a pair of water cooled slit. The slit movement is pneumatically controlled as it has to be operated in high magnetic field. The computer controlled drive system can move the elements precisely. The paper will describe the drive system and its control mechanism.

Poster THPD19 [0.933 MB]

THPD20

RF Distribution and Control System for Accelerators of the VEC-RIB Facility

controls, LLRF, cavity, low-level-rf

184

H.K. Pandey, S. Basak, D.P. Dutta, T.K. Mandi
VECC, Kolkata, India
A. Kumar, K. P. Ray
SAMEER, Kolkata, India

RIB facility at VECC has several heavy ion linear accelerators like RFQ, two IH-LNACs and one buncher cavity operating at 37.8 MHz and two IH-LINACs with one buncher cavity at 75.6 MHz. Some more RF cavities are being designed at the third harmonic of 37.8 MHz and will be added in the RIB beam line. All the cavities have separate RF power amplifiers with proper amplitude, phase and resonance frequency tuning and control system for efficient and stable operation. The LLRF control system has been operational for the power amplifiers of the existing RF cavities and improved design and development is carried out. The main features of the RF control system are phase and amplitude control of the RF input to the amplifiers and tuning of the RF cavity to the desired resonant frequency with automation using feedback control. It will also have various interlocks for the safety of the load as well as the amplifier. A micro-controller based data acquisition and processing system is being used for control and local/remote operation. The RF distribution system as well as the design details of RF control system will be presented in this paper.

Poster THPD20 [2.163 MB]

THPD35

Modeling and Simulation of Indus-2 RF Feedback Control System

cavity, simulation, controls, LLRF

208

D. Sharma, P.S. Bagduwal, P.R. Hannurkar, M. Lad, N. Tiwari
RRCAT, Indore (M.P.), India

Funding: RRCAT, Indore, Department of Atomic Energy, Government of India
The Indus-2 synchrotron radiation source has four RF stations along with their feedback control systems. For higher beam energy and current operation, amplitude and phase feedback control systems of Indus-2 are being upgraded. To understand the behavior of amplitude and phase control loop under different operating conditions, modeling and simulation of RF feedback control system is done. RF cavity base band quadrature domain model has been created due to its close correspondence with actual implementation and better computational efficiency which make the simulation faster. Correspondence between base band and actual RF cavity model is confirmed by comparing their simulation results. Base band Cavity model was studied under different operating conditions. LLRF feed back control system simulation is done using the same cavity model. Error signals are intentionally generated and response of the closed loops system is observed. With implementation of feedback control loop, broadening in the RF cavity bandwidth was also observed in terms of reduction in cavity fill time. Simulation will help us in optimizing parameters of upgraded LLRF system for higher beam energy and current operation.

Poster THPD35 [0.698 MB]

FRID01

Introducing the !CHAOS Control Systems Framework

controls, GUI

282

L. Catani, F. Zani
INFN-Roma II, Roma, Italy
C. Bisegni, D. Di Giovenale, G. Di Pirro, L.G. Foggetta, G. Mazzitelli, A. Stecchi
INFN/LNF, Frascati (Roma), Italy

The analysis of most recent developments on high-performance software technologies suggests that new a design of distributed control systems (DCS) for particle accelerators may profit from solutions borrowed from cutting-edge Internet services. To fully profit from this new technologies the DCS model should be reconsidered, thus leading to the definition of a new paradigm. In this paper we present the conceptual design of a new control system for a particle accelerator and associated machine data acquisition system (DAQ), based on a synergic combination of a non-relational key/value database (KVDB) and network distributed object caching (DOC). The use of these technologies, to implement continuous data archiving and data distribution between components respectively, brought about the definition of a new control system concept offering a number of interesting features such as a high level of abstraction of services and components and their integration in a framework that can be seen as a comprehensive control services provider for GUI applications, front-end controllers, measurement and feedback procedures etc.