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Description: This paper presents the results of a parametric investigation of the various Aladdin lattices that have been considered as part of the Aladdin Upgrade Study, the overall purpose of which is to assess the problems with the existing Aladdin storage ring and recommend corrective action. In particular, the Study is to confirm the parameters of a full-energy injector for Aladdin and to identify those components that need upgrading or redesigning to guarantee satisfactory performance with the new injector. As part of the Study, an investigation has been carried out on several different lattices, referred to in this document as Aladdin-1, Aladdin-2, and Aladdin-3. These lattices have been provided as part of the activities of the Lattice Group (led by A. Ruggiero) by various members of the Argonne National Laboratory. The first lattice is intended to be identical to the presently operating Aladdin; the second lattice has the same spatial arrangement of magnets but - by the addition of power supplies - more flexibility in optimizing lattice functions (e.g., for injection or for the eventual inclusion of insertion devices); the third lattice corresponds closely to the working BESSY lattice and would require the physical relocation of various magnets (while providing the potential advantage of a significantly improved natural emittance). An abridged parameter list for the three lattices is given in Table I.
Date: March 1, 1985
Creator: Zisman, M.S.
Partner: UNT Libraries Government Documents Department

Designing PV Incentive Programs to Promote Performance: A Reviewof Current Practice

Description: Increasing levels of financial support for customer-sited photovoltaic (PV) systems, provided through publicly-funded incentive programs, has heightened concerns about the long-term performance of these systems. Given the barriers that customers face to ensuring that their PV systems perform well, and the responsibility that PV incentive programs bear to ensure that public funds are prudently spent, these programs should, and often do, play a critical role in ensuring that PV systems receiving incentives perform well. To provide a point of reference for assessing the current state of the art, and to inform program design efforts going forward, we examine the approaches to encouraging PV system performance used by 32 prominent PV incentive programs in the U.S. We identify eight general strategies or groups of related strategies that these programs have used to address performance issues, and highlight important differences in the implementation of these strategies among programs.
Date: June 1, 2007
Creator: Barbose, Galen; Wiser, Ryan & Bolinger, Mark
Partner: UNT Libraries Government Documents Department

Development of a High-Pressure/High-Temperature Downhole Turbine Generator

Description: The objective of this project as originally outlined has been to achieve a viable downhole direct current (DC) power source for extreme high pressure, high temperature (HPHT) environments of >25,000 psi and >250 C. The Phase I investigation posed and answered specific questions about the power requirements, mode of delivery and form factor the industry would like to see for downhole turbine generator tool for the HPHT environment, and noted specific components, materials and design features of that commercial system that will require upgrading to meet the HPHT project goals. During the course of Phase I investigation the scope of the project was HPHT downhole DC power. Phase I also investigated the viability of modifying a commercial expanded, without additional cost expected to the project, to include the addition of HT batteries to the power supply platform.
Date: February 1, 2007
Creator: Price, Timothy F.
Partner: UNT Libraries Government Documents Department

What Changed in Article 690-Solar Photovoltaic Systems- of the 1999 National Electrical Code?

Description: Article 690, Solar Photovoltaic Power Systems, has been in the National Electrical Code (NEC) since 1984. An NFPA-appointed Task Group for Article 690 proposed changes to Article 690 for both the 1996 and 1999 codes. The Task Group, supported by more than 50 professionals from throughout the photovoltaic (PV) industry, met seven times during the 1999 code cycle to integrate the needs of the industry with the needs of electrical inspectors and end users to ensure the safety of PV systems. The Task Group proposed 57 changes to Article 690, and all the changes were accepted in the review process. The performance and cost of PV installations were always a consideration as these changes were formed but safety was the number-one priority. All of the proposals were well substantiated and coordinated throughout the PV industry and with representatives of Underwriters Laboratories, Inc (UL). The most significant changes that were made in Article 690 for the 1999 NEC along with some of the rationale are discussed in the remainder of this article.
Date: January 12, 1999
Creator: Bower, W. & Wiles, J.
Partner: UNT Libraries Government Documents Department

Progress on PEP-II magnet power conversion system

Description: The various power systems for supplying the PEP-II DC magnets rely exclusively on switchmode conversion, utilizing a variety of means depending on the requirements. All of the larger power supplies, ranging from 10 to 200 kW, are powered from DC sources utilizing rectified 480 V AC. Choppers can be used for the series connected strings, but for smaller groups and individual magnets, inverters driving high-frequency transformers with rectifiers comprise the best approach. All of the various systems use a ``building block`` approach of multiple standard-size units connected in series or parallel to most cost-effectively deal with a great range of voltage and current requirements. Utilization of existing infrastructure from PEP-I has been a cost-effective determinant. Equipment is being purchased either off-the-shelf, through performance specification, or by hardware purchase based on design-through-prototype. The corrector magnet power system, utilizing inexpensive, off-the-shelf, four-quadrant switching motor-controllers, has already proven very reliable: 120 of the total of 900 units have been running on the injection system for four months with no failures.
Date: June 4, 1996
Creator: Bellomo, P.; Genova, L.; Jackson, T. & Shimer, D.
Partner: UNT Libraries Government Documents Department

The New 1999 National Electrical Code Coupled with New Standards Clarify Requirements for Installations of Photovoltaic Systems in the U.S.

Description: The National Electrical Code@ (NEC@) focuses primarily on electrical system installation requirements in the U.S. The NEC addresses both fire and personnel safety. This paper will describe recent efforts of the PV industry in the U.S. and the resulting requirements in the 1999 National Electrical Code-- Article 690 --Solar Photovoltaic Systems. The Article 690 requirements spell out the PV-unique requirements for safe installations of PV systems in the U.S.A. This paper provides an overview of the most significant changes that appear in Article 690 of the 1999 edition of the NEC. The related and coordinated efforts of the other standards- making groups will also be briefly reviewed.
Date: January 8, 1999
Creator: Bower, W.
Partner: UNT Libraries Government Documents Department

The Use of Thyristors for Repetitive Narrow Pulse, High Power Switching

Description: Inverter type thyristors were switched repetitively to failure with 1 {micro}s pulses at repetition rates of 10, 50 and 100 pps and at peak currents up to 12 kA. Millions of pulses could be obtained before failure if the peak current were held at around 6 kA.
Date: January 13, 2000
Partner: UNT Libraries Government Documents Department

Photovoltaic system reliability

Description: This paper discusses the reliability of several photovoltaic projects including SMUD`s PV Pioneer project, various projects monitored by Ascension Technology, and the Colorado Parks project. System times-to-failure range from 1 to 16 years, and maintenance costs range from 1 to 16 cents per kilowatt-hour. Factors contributing to the reliability of these systems are discussed, and practices are recommended that can be applied to future projects. This paper also discusses the methodology used to collect and analyze PV system reliability data.
Date: October 1, 1997
Creator: Maish, A.B.; Atcitty, C. & Greenberg, D.
Partner: UNT Libraries Government Documents Department

International photovoltaic products and manufacturers directory, 1995

Description: This international directory of more than 500 photovoltaic-related manufacturers is intended to guide potential users of photovoltaics to sources for systems and their components. Two indexes help the user to locate firms and materials. A glossary describes equipment and terminology commonly used in the photovoltaic industry.
Date: November 1, 1995
Creator: Shepperd, L.W. & Florida Solar Energy Center, Cocoa, FL (United States)]
Partner: UNT Libraries Government Documents Department

Analysis techniques used on field degraded photovoltaic modules

Description: Sandia National Laboratory`s PV System Components Department performs comprehensive failure analysis of photovoltaic modules after extended field exposure at various sites around the world. A full spectrum of analytical techniques are used to help identify the causes of degradation. The techniques are used to make solder fatigue life predictions for PV concentrator modules, identify cell damage or current mismatch, and measure the adhesive strength of the module encapsulant.
Date: September 1, 1995
Creator: Hund, T.D. & King, D.L.
Partner: UNT Libraries Government Documents Department

Reliability of Rechargeable Batteries in a Photovoltaic Power Supply System

Description: We investigate the reliability If a rechargeable battery acting as the energy storage component in a photovoltaic power supply system. A model system was constructed for this that includes the solar resource, the photovoltaic power supp Iy system, the rechargeable battery and a load. The solar resource and the system load are modeled as SI ochastic processes. The photovoltaic system and the rechargeable battery are modeled deterministically, imd an artificial neural network is incorporated into the model of the rechargeable battery to simulate dartage that occurs during deep discharge cycles. The equations governing system behavior are solved simultaneously in the Monte Carlo framework and a fwst passage problem is solved to assess system reliability.
Date: November 30, 1998
Creator: Barney, P.; Jungst, R.G., Ingersoll, D.; O'Gorman, C.; Paez, T.L. & Urbina, A.
Partner: UNT Libraries Government Documents Department

Photovoltaic module performance and durability following long-term field exposure

Description: Our investigations of both new and field-aged photovoltaic modules have indicated that, in general, today's commercially available modules area highly reliable product. However, by using new test procedures, subtle failure mechanisms have also been identified that must be addressed in order to achieve 30-year module lifetimes. This paper summarizes diagnostic test procedures, results, and implications of in-depth investigations of the performance and durability characteristics of commercial modules after long-term field exposure. A collaborative effort with U.S. module manufacturers aimed at achieving 30-year module lifetimes is also described.
Date: September 8, 1998
Creator: Ellibee, D.E.; Hansen, B.R.; King, D.L.; Kratochvil, J.A. & Quintana, M.A.
Partner: UNT Libraries Government Documents Department