Download or read book ANALYSIS OF THE SNS SUPERCONDUCTING RF CONTROL SYSTEM written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis and Design of Resonant Frequency Control Systems with Applications written by Daniel Smith and published by . This book was released on 2007 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies of Electron Activities in SNS type Superconducting Rf Cavities written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: During vertical testing of SNS superconducting RF cavities, a lot of electron activity was observed. This could be evidence of in-cell multipacting, cell to cell electron mitigation or near-axis dark current. To study the potential for these electron activities in SRF cavities, a multi-purpose electron tracking code (FishPact) was developed based on the Poisson/Superfish Field solvers. Electron trajectories between the impacts in both medium-[beta] and high-[beta] cavities are tracked under varying accelerating gradient (E{sub acc}), RF phases, and emission locations. It is found that the high beta cavities show a greater propensity for potential sources of dark current than their medium beta counterparts. It is further proposed that field emission induced multipacting is a potential, though rare, source of further Q0 degradation.
Download or read book RF Superconductivity written by Hasan Padamsee and published by John Wiley & Sons. This book was released on 2009-03-30 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the second book to RF Superconducting, written by one of the leading experts. The book provides fast and up-to-date access to the latest advances in the key technology for future accelerators. Experts as well as newcomers to the field will benefit from the discussion of progress in the basic science, technology as well as recent and forthcoming applications. Researchers in accelerator physics will also find much that is relevant to their discipline.
Download or read book Tuner Effect on the Field Flatness of SNS Superconducting RF Cavity written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The field flatness (FF) in a multi-cell superconducting cavity affects not only net accelerating voltage, but also peak surface field [1] and Lorentz detuning coefficient [2]. Our measurements indicate that the tuner's motion changes not only the cavity frequency but also its FF. This field amplitude change is a linear tilt and proportional to the distance between each cell center and the cavity's geometric center. This tilt also changes the coupling of the Fundamental Power Coupler (FPC) and Field Probe (FP) on either side of the cavity. The tilt has been measured and simulated, and is ≈20%/MHz on the Spallation Neutron Source (SNS) medium [beta] cavities. The FF change is not only due to the uneven volume change within the cell, but also due to the cell-to-cell coupling.
Download or read book Frequency Shift Observer for SNS Superconducting RF Cavity written by and published by . This book was released on 2002 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: In contrast to a normal conducting RF cavity, a superconducting RF cavity is very susceptible to shifts in its resonance frequency. The main sources of the shift are Lorentz force detuning and microphonics. In SNS, to compensate for the frequency shift, a feedforward control is to be applied. In this paper, as an initiative step, a frequency shift observer is proposed which is simple enough to be implemented with a digital signal processor in real time. Simulation results of the proposed frequency shift observer show reliable performance and acceptable computation time for the real time implementation.
Download or read book RF Conditioning and Testing of Fundamental Power Couplers for SNS Superconducting Cavity Production written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Spallation Neutron Source (SNS) makes use of 33 medium beta (0.61) and 48 high beta (0.81) superconducting cavities. Each cavity is equipped with a fundamental power coupler, which should withstand the full klystron power of 550 kW in full reflection for the duration of an RF pulse of 1.3 msec at 60 Hz repetition rate. Before assembly to a superconducting cavity, the vacuum components of the coupler are submitted to acceptance procedures consisting of preliminary quality assessments, cleaning and clean room assembly, vacuum leak checks and baking under vacuum, followed by conditioning and RF high power testing. Similar acceptance procedures (except clean room assembly and baking) were applied for the airside components of the coupler. All 81 fundamental power couplers for SNS superconducting cavity production have been RF power tested at JLAB Newport News and, beginning in April 2004 at SNS Oak Ridge. This paper gives details of coupler processing and RF high power-assessed performances.
Download or read book Iterative Learning Control written by Hyo-Sung Ahn and published by Springer Science & Business Media. This book was released on 2007-06-28 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph studies the design of robust, monotonically-convergent iterative learning controllers for discrete-time systems. It presents a unified analysis and design framework that enables designers to consider both robustness and monotonic convergence for typical uncertainty models, including parametric interval uncertainties, iteration-domain frequency uncertainty, and iteration-domain stochastic uncertainty. The book shows how to use robust iterative learning control in the face of model uncertainty.
Download or read book RF Processing of the Couplers for the SNS Superconducting Cavities written by T. Powers and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: All eighty-one fundamental power couplers for the 805 MHz superconducting cavities of the SNS linac have been RF conditioned and installed in the cryomodules successfully. The couplers were RF processed at JLAB or at the SNS in ORNL: more than forty couplers have been RF conditioned in the SNS RF Test Facility (RFTF) after the first forty couplers were conditioned at JLAB. The couplers were conditioned up to 650 kW forward power at 8% duty cycle in traveling and standing waves. They were installed on the cavities in the cryomodules and then assembled with the airside waveguide transitions. The couplers have been high power RF tested with satisfactory accelerating field gradients in the cooled cavities.
Download or read book A Design and Performance Analysis Tool for Superconducting RF Systems written by and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Superconducting rf systems are usually operated with continuous rf power or with rf pulse lengths exceeding 1 ms to maximize the overall wall plug power efficiency. Typical examples are CEBAF at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) and the TESLA Test Facility at DESY. The long pulses allow for effective application of feedback to stabilize the accelerating field in presence of microphonics, Lorentz force detuning, and fluctuations of the beam current. In this paper the authors describe a set of tools to be used with MATLAB and SIMULINK, which allow to analyze the quality of field regulation for a given design. The tools include models for the cavities, the rf power source, the beam, sources of field perturbations, and the rf feedback system. The rf control relevant electrical and mechanical characteristics of the cavity are described in form of time-varying state space models. The power source is modeled as a current generator and includes saturation characteristics and noise. An arbitrary time structure can be imposed on the beam current to reflect a macro-pulse structure and bunch charge fluctuations. For rf feedback several schemes can be selected: Traditional amplitude and phase control as well as I/Q control. The choices for the feedback controller include analog or digital approaches and various choices of frequency response. Feed forward can be added to further suppress repetitive errors. The results of a performance analysis of the CEBAF and the TESLA Linac rf system using these tools are presented.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1987 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Power RF Test Facility at the SNS written by D. E. Anderson and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: RF Test Facility has been completed in the SNS project at ORNL to support test and conditioning operation of RF subsystems and components. The system consists of two transmitters for two klystrons powered by a common high voltage pulsed converter modulator that can provide power to two independent RF systems. The waveguides are configured with WR2100 and WR1150 sizes for presently used frequencies: 402.5 MHz and 805 MHz. Both 402.5 MHz and 805 MHz systems have circulator protected klystrons that can be powered by the modulator capable of delivering 11 MW peak and 1 MW average power. The facility has been equipped with computer control for various RF processing and complete dual frequency operation. More than forty 805 MHz fundamental power couplers for the SNS superconducting linac (SCL) cavities have been RF conditioned in this facility. The facility provides more than 1000 ft2 floor area for various test setups. The facility also has a shielded cave area that can support high power tests of normal conducting and superconducting accelerating cavities and components.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Publications of the National Institute of Standards and Technology Catalog written by National Institute of Standards and Technology (U.S.) and published by . This book was released on 1994 with total page 1162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book RF Linear Accelerators written by Thomas P. Wangler and published by John Wiley & Sons. This book was released on 2008-03-03 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dieses einschlägige Lehrbuch, entwickelt auf der Grundlage der Ausbildung an der US Particle Accelerator School, schließt eine Lücke in der verfügbaren Literatur zum Thema Hochfrequenz-Linearbeschleuniger, kurz RF-Linac. Nach einer Erläuterung der naturwissenschaftlichen Grundlagen und der neuesten technologischen Eckdaten stellt diese zweite Auflage neueste RF-Linacs, spezialisierte Systeme, Systeme mit Supraleitern und verschiedene Spezialverfahren vor. Übungsaufgaben an den Kapitelenden erleichtern das Einprägen und das Nacharbeiten von Vorlesungen.
Download or read book Beam Instrumentation Workshop 2002 written by Gary A. Smith and published by American Institute of Physics. This book was released on 2002-12-06 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proceedings of the 10th Beam Instrumentation Workshop contains papers discussing the design principles and engineering issues of beam diagnostic and control instrumentation for charged particle accelerators and beam transport lines. The papers, presented at the 2002 Workshop, consist of tutorials, invited talks, and contributed oral and poster presentations.
Download or read book Optomechatronic Sensors Actuators and Control written by Kee S. Moon and published by SPIE-International Society for Optical Engineering. This book was released on 2004 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of SPIE present the original research papers presented at SPIE conferences and other high-quality conferences in the broad-ranging fields of optics and photonics. These books provide prompt access to the latest innovations in research and technology in their respective fields. Proceedings of SPIE are among the most cited references in patent literature.
