255 Matching Results

Search Results

Advanced search parameters have been applied.

Industrial Applications Perspective of Nanodielectrics

Description: The field of nanodielectrics has had a significant impact on voltage endurance characteristics of electrical insulation. Improved time-to-breakdown behavior, resulting in reduced aging of insulation, and enhanced thermal stability are of considerable importance in industrial applications. This chapter discusses several specific aspects of nanodielectrics and their role in the future of electrical insulation and dielectric sciences.
Date: January 1, 2009
Creator: Tuncer, Enis & Sauers, Isidor
Partner: UNT Libraries Government Documents Department

Testing of ITER central solenoid coil insulation in an array

Description: A glass-polyimide insulation system has been proposed by the US team for use in the Central Solenoid (CS) coil of the international Thermonuclear Experimental Reactor (ITER) machine and it is planned to use this system in the CS model coil inner module. The turn insulation will consist of 2 layers of combined prepreg and Kapton. Each layer is 50% overlapped with a butt wrap of prepreg and an overwrap of S glass. The coil layers will be separated by a glass-resin composite and impregnated in a VPI process. Small scale tests on the various components of the insulation are complete. It is planned to fabricate and test the insulation in a 4 x 4 insulated CS conductor array which will include the layer insulation and be vacuum impregnated. The conductor array will be subjected to 20 thermal cycles and 100000 mechanical load cycles in a Liquid Nitrogen environment. These loads are similar to those seen in the CS coil design. The insulation will be electrically tested at several stages during mechanical testing. This paper will describe the array configuration, fabrication: process, instrumentation, testing configuration, and supporting analyses used in selecting the array and test configurations.
Date: September 29, 1995
Creator: Jayakumar, R.; Martovetsky, N.N. & Perfect, S.A.
Partner: UNT Libraries Government Documents Department

Compatibility of refrigerants and lubricants with electrical sheet insulation under retrofit conditions

Description: To determine whether exposure to the original refrigerant/mineral oil would affect compatibility of sheet insulation with alternative refrigerant/lubricant after retrofit, sheet insulation was exposed at elevated temperature to the original refrigerant and mineral oil for 500 hours, followed by exposure to the alternative refrigerant and lubricant for 500 hours. Most of the sheet insulation materials exposed to the alternative refrigerant and lubricant (after an initial exposure to the original refrigerant and mineral oil) appeared to be compatible with the alternative refrigerant and lubricant. The only concern was delamination and blistering of the sheet insulation containing Nomex, especially after removal of absorbed refrigerant at high temperature. This was attributed to incompatibility of the adhesive and not to the Nomex itself. Embrittlement of the polyethylene terephthalate (PET) sheet was initially observed, but 2048 subsequent tests under extremely dry conditions showed that embrittlement of the PET materials was attributed to moisture present during the exposure.
Date: November 1, 1996
Creator: Doerr, R.G. & Waite, T.D.
Partner: UNT Libraries Government Documents Department

Aging analyses of aircraft wire insulation

Description: Over the past two decades, Sandia has developed a variety of specialized analytical techniques for evaluating the long-term aging and stability of cable insulation and other related materials. These techniques have been applied to cable reliability studies involving numerous insulation types and environmental factors. This work has allowed the monitoring of the occurrence and progression of cable material deterioration in application environments, and has provided insights into material degradation mechanisms. It has also allowed development of more reliable lifetime prediction methodologies. As a part of the FAA program for intrusive inspection of aircraft wiring, they are beginning to apply a battery of techniques to assessing the condition of cable specimens removed from retired aircraft. It is anticipated that in a future part of this program, they may employ these techniques in conjunction with accelerated aging methodologies and models that the authros have developed and employed in the past to predict cable lifetimes. The types of materials to be assessed include 5 different wire types: polyimide, PVC/Glass/Nylon, extruded XL-polyalkene/PVDF, Poly-X, and XL-ETFE. This presentation provides a brief overview of the main techniques that will be employed in assessing the state of health of aircraft wire insulation. The discussion will be illustrated with data from their prior cable aging studies, highlighting the methods used and their important conclusions. A few of the techniques that they employ are widely used in aging studies on polymers, but others are unique to Sandia. All of their techniques are non-proprietary, and maybe of interest for use by others in terms of application to aircraft wiring analysis. At the end of this report is a list showing some leading references to papers that have been published in the open literature which provide more detailed information on the analytical techniques for elastomer aging studies. The first step in ...
Date: May 8, 2000
Partner: UNT Libraries Government Documents Department

Compatibility of R-245ca with motor materials under retrofit conditions

Description: This document, which is a reproduction of slides from a presentation at the June 1995 ASHRAE conference, evaluates and provides data on a number of motor parameters after the motor materials have been exposed to the refrigerant R-245ca. Data on conditions of the insulating varnish, the magnet wire, the insulations, and the elastomers are presented, as well as a note on work in progress. While it was concluded that most materials are compatible with R-245ca under retrofit conditions, it was also noted that the flammability, toxicity, efficiency, and cost of R-245ca and/or Blends are unresolved.
Date: July 1, 1995
Creator: Doerr, R.G. & Waite, T.D.
Partner: UNT Libraries Government Documents Department

Assessment of the non-destructive nature of PASD on wire insulation integrity.

Description: The potential of a new cable diagnostic known as Pulse-Arrested Spark Discharge technique (PASD) is being studied. Previous reports have documented the capability of the technique to locate cable failures using a short high voltage pulse. This report will investigate the impact of PASD on the sample under test. In this report, two different energy deposition experiments are discussed. These experiments include the PASD pulse ({approx}6 mJ) and a high energy discharge ({approx}600 mJ) produced from a charged capacitor source. The high energy experiment is used to inflict detectable damage upon the insulators and to make comparisons with the effects of the low energy PASD pulse. Insulator breakdown voltage strength before and after application of the PASD pulse and high energy discharges are compared. Results indicate that the PASD technique does not appear to degrade the breakdown strength of the insulator or to produce visible damage. However, testing of the additional materials, including connector insulators, may be warranted to verify PASDs non-destructive nature across the full spectrum of insulators used in commercial aircraft wiring systems.
Date: September 1, 2003
Creator: Lockner, Thomas Ramsbeck; Peña, Gary Edward; Schneider, Larry X.; Higgins, Matthew B. & Glover, Steven Frank
Partner: UNT Libraries Government Documents Department

Corona and Motor Voltage Interim Report

Description: It has been suggested that to meet the FreedomCAR objectives for cost, size, weight, efficiency, and reliability higher buss voltages be utilized in HEV and FC automotive applications. The reasoning is that since electric power is equal to the product of voltage and current for a given power a higher voltage and lower current would result in smaller cable and inverter switching components. Consequently, the system can be lighter and smaller. On the other hand, higher voltages are known to require better and thicker electrical insulation that reduce the available slot area for motor windings. One cause of slow insulation breakdown is corona that gradually erodes the insulation and shortens the life expectancy of the motor. This study reports on the results of a study on corona initiating voltages for mush-wound and bobbin-wound stators. A unique testing method is illustrated.
Date: May 6, 2005
Creator: Hsu, J.S.
Partner: UNT Libraries Government Documents Department

The development of ShortWatch, a novel overtemperature or mechanical damage sensing technology for wires or cables. Final report

Description: 'ShortWatch' is a patented technology which for the first time offers electrical wire/cable products providing real-time, 'in-situ' (1) condition monitoring that warns of insulation damage before an electrical fault occurs, (2) assessment of the ability to perform in a Design Basis event, (3) distributed sensor warning of overtemperature, and (4) insulation leakage measurement capability providing arc sensing and a reliable tool for wire age prediction.
Date: September 7, 2001
Creator: Watkins, Ken; Morris, Jack; Wong, C.P. & Luo, Shijian
Partner: UNT Libraries Government Documents Department

High-Temperature Motor Windings for Downhole Pumps Used in Geothermal Energy Production

Description: The development of highly reliable downhole equipment is an essential element in enabling the widespread utilization of Enhanced Geothermal Systems (EGS). The downhole equipment used in these systems will be required to operate at high voltages and temperatures on the order of 200 to 250°C (and eventually to 300˚C). These conditions exceed the practical operating ranges of currently available thermoplastic wire insulations, and thus limit the operating lifetime of tools such as Electric Submersible Pumps (ESPs). In this work, high-temperature insulations based on composite materials were developed and demonstrated. The products of this work were found to exhibit electrical resistivities and dielectric breakdown strengths that PEEK at temperatures above 250C. In addition, sub-scale motor windings were fabricated and tested to validate the performance of this technology
Date: December 31, 2010
Creator: Hooker, Matthew; Hazelton, Craig & Kano, Kimi
Partner: UNT Libraries Government Documents Department

Design considerations and data for gas-insulated high voltage structures

Description: This paper is intended to benefit the person faced with the occasional task of designing gas insulated high-voltage structures or spark gaps and who must decide upon the proper geometry, spacings, gas type, and pressure for reliable voltage-holding. An approach is presented along with a summary of how various factors affect voltage breakdown. The design procedures described apply to situations where the influence of nearby insulators is negligible. The accuracy of the data is estimated to be within 10 to 15 percent, a value usually attained in practice only when one follows the cautionary advice discussed in the paragraphs on materials preparation, gas properties, and conditioning. (auth)
Date: November 1, 1975
Creator: Hopkins, D.B.
Partner: UNT Libraries Government Documents Department

Electrical insulation for large multiaxis superconducting magnets

Description: The selection of interturn and interlayer insulation for superconducting magnets is discussed. The magnet problems of the Baseball II device are described. Manufacture of the insulation and radiation damage are mentioned. A planned experimental program is outlined. (MOW)
Date: October 30, 1975
Creator: Harvey, A.R. & Rinde, J.A.
Partner: UNT Libraries Government Documents Department

Compatibility of refrigerants and lubricants with motor materials under retrofit conditions

Description: Compatibility tests were conducted on motor materials to determine whether exposure to the original refrigerant/mineral oil would affect compatibility of the motor materials with the alternative refrigerant/lubricant after retrofit. The motor materials were exposed at elevated temperature to the original refrigerant and mineral oil for 500 hours, followed by exposure to the alternative refrigerant and lubricant for 500 hours. Motor materials exposed to the alternative refrigerant and lubricant (after an initial exposure to the original refrigerant and mineral oil) appeared to be compatible with the alternative refrigerant and lubricant. The only concern was delamination and blistering of the sheet insulation containing Nomex, especially after removal of absorbed refrigerant at high temperature. This was attributed to incompatibility of the adhesive and not to the Nomex itself. Embrittlement of the polyethylene terephthalate (PET) sheet and sleeving insulations was initially observed, but subsequent tests under extremely dry conditions showed that embrittlement of the PET materials was attributed to moisture present during the exposure.
Date: December 1, 1995
Creator: Doerr, R.G. & Waite, T.D.
Partner: UNT Libraries Government Documents Department

DOE Fire Protection Handbook, Volume II. Fire effects and electrical and electronic equipment

Description: Electrical and electronic equipment, including computers, are used at critical facilities throughout the Department of Energy (DOE). Hughes Associates, Inc. was tasked to evaluate the potential thermal and nonthermal effects of a fire on the electrical and electronic equipment and methods to analyze, evaluate, and assist in controlling the potential effects. This report is a result of a literature review and analysis on the effects of fire on electrical equipment. It is directed at three objectives: (1) Provide a state-of-the-art review and analysis of thermal and nonthermal damage to electrical and electronic equipment; (2) Develop a procedure for estimating thermal and nonthermal damage considerations using current knowledge; and (3) Develop an R&D/T&E program to fill gaps in the current knowledge needed to further perfect the procedure. The literature review was performed utilizing existing electronic databases. Sources searched included scientific and engineering databases including Dialog, NTIS, SciSearch and NIST BFRL literature. Incorporated in the analysis is unpublished literature and conversations with members of the ASTM E-5.21, Smoke Corrosivity, and researchers in the electronics field. This report does not consider the effects of fire suppression systems or efforts. Further analysis of the potential impact is required in the future.
Date: August 18, 1994
Partner: UNT Libraries Government Documents Department

Fabrication of intermetallic coatings for electrical insulation and corrosion resistance on high-temperature alloys

Description: Several intermetallic films were applied to high-temperature alloys (V alloys and 304, 316 stainless steels) to provide electrical insulation and corrosion resistance. Alloy grain growth at 1000 C for the V-5Cr-5Ti alloy was investigated to determine stability of the alloy substrate during coating formation by CVD or metallic vapor processes at 800-850 C. Film layers were examined by optical and scanning electron microscopy and by electron-energy-dispersive and XRD analysis; they were also tested for electrical resistivity and corrosion resistance. Results elucidated the nature of the coatings, which provided both electrical insulation and high-temperature corrosion protection.
Date: November 1, 1996
Creator: Park, J.-H. & Cho, W.D.
Partner: UNT Libraries Government Documents Department

Thermal resistance across a copper/Kapton/copper interface at cryogenic temperatures

Description: The high-{Tc} superconductor current lead heat intercept connection, which is utilized as a thermal intercept to remove the Joule heat from the upper stage lead to a heat sink operating at 50--77 K, consists of a structure where a 152-{micro}m film is sandwiched between two concentric copper cylinders. The material chosen for the insulating film is Kapton MT, a composite film which has a relatively low thermal resistance, but yet a high voltage standoff capability. Here, the measured thermal conductance of a copper/Kapton MT/copper junction in a flat-plate geometry is compared to the results obtained from the actual heat intercept connection. Increasing the contact pressure reduces the thermal resistance to a minimum value determined by the film conduction resistance. A comparison between the resistance of the copper/Kapton MT/copper junction and a copper/G-10/copper junction demonstrates that the Kapton MT layer yields a lower thermal resistance while still providing adequate electrical isolation.
Date: September 1997
Creator: Zhao, L.; Phelan, P. E.; Niemann, R. C. & Weber, B. R.
Partner: UNT Libraries Government Documents Department

Power conversion technologies

Description: The Power Conversion Technologies thrust area identifies and sponsors development activities that enhance the capabilities of engineering at Lawrence Livermore National Laboratory (LLNL) in the area of solid- state power electronics. Our primary objective is to be a resource to existing and emerging LLNL programs that require advanced solid-state power electronic technologies.. Our focus is on developing and integrating technologies that will significantly impact the capability, size, cost, and reliability of future power electronic systems. During FY-96, we concentrated our research efforts on the areas of (1) Micropower Impulse Radar (MIR); (2) novel solid-state opening switches; (3) advanced modulator technology for accelerators; (4) compact accelerators; and (5) compact pulse generators.
Date: February 1, 1997
Creator: Newton, M. A.
Partner: UNT Libraries Government Documents Department

Investigation of Cable Insulation and Mechanical Properties of Niobium-Tin Composite

Description: As a part of the Fermilab high field Nb{sub 3}Sn dipole development program, various issues of magnet technology are being investigated. In cable insulation development, S-2 fiber glass sleeve and a new ceramic insulation developed by Composite Technology Development Inc. (CTD) were studied as a possible candidates. For each type of insulation, Nb{sub 3}Sn ten-stack samples were reacted and then vacuum impregnated with epoxy. Measurements of modulus of elasticity and Poisson�s ratio under compression were made at room temperature and at 4.2 K. For comparison, an epoxy impregnated NbTi composite was also tested.
Date: April 23, 1999
Creator: D.R. Chichili, T.T. Arkan and I. Terechkine
Partner: UNT Libraries Government Documents Department

Pulse Capacitors for Next Generation Linear Colliders. Final Report

Description: During this Phase I SBIR research program, Nanomaterials Research Corporation (NRC) successfully demonstrated high-voltage multilayer capacitors produced from sub-100 nm ceramic powders. The devices produced by NRC exhibited properties that make them particularly useful for pulse power applications. These properties include (1) high capacitance (2) low loss (3) high breakdown voltage (4) high insulation resistance and (5) rapid discharge characteristics. Furthermore, the properties of the nanostructured capacitors were consistently found to exceed those of components that represent the state of the art within the industry. Encouraged by these results, NRC is planning to submit a Phase II proposal with the objective of securing seed capital to continue this development effort.
Date: March 3, 2000
Creator: Hooker, M.W.
Partner: UNT Libraries Government Documents Department

Ultrathin diamond-like carbon films deposited by filtered carbon vacuum arcs

Description: Ultrathin (< 5 nm) hard carbon films are of great interest to the magnetic storage industry as the areal density approaches 100 Gbit/in{sup 2}. These films are used as overcoats to protect the magnetic layers on disk media and the active elements of the read-write slider. Tetrahedral amorphous carbon films can be produced by filtered cathodic arc deposition, but the films will only be accepted by the storage industry only if the ''macroparticle'' issue has been solved. Better plasma filters have been developed over recent years. Emphasis is put on the promising twist filter system - a compact, open structure that operates with pulsed arcs and high magnetic field. Based on corrosion tests it is shown that the macroparticle reduction by the twist filter is satisfactory for this demanding application, while plasma throughput is very high. Ultrathin hard carbon films have been synthesized using S-filter and twist filter systems. Film properties such as hardness, elastic modulus, wear, and corrosion resistance have been tested.
Date: July 13, 2001
Creator: Anders, Andre; Fong, Walton; Kulkarni, Ashok; Ryan, Francis W. & Bhatia, C. Singh
Partner: UNT Libraries Government Documents Department

Development of electrically insulating coatings on vanadium alloys for lithium-cooled blankets

Description: The self-cooled lithium blanket concept with a vanadium structure offers a potential for high performance with attractive safety and environmental features. Based on blanket design studies, it became apparent that electrically insulating duct walls would be required to reduce the magnetohydrodynamic (MHD) pressure drop for liquid metal-cooled blankets for high magnetic field fusion devices. As a result, development of insulator coatings was recommended as the most appropriate approach for resolving this issue. Oxides such as CaO, Y{sub 2}O{sub 3}, BeO, MgO, MgAl{sub 2}O{sub 4}, and Y{sub 3}Al{sub 2}O{sub 12} and nitrides such as AlN, BN and Si{sub 3}N{sub 2} were initially considered potential candidate coating materials. Based on results of scoping studies, CaO and AlN have been selected as primary candidates for further development. Progress on the development of CaO and AlN coatings, including in-situ formation and electrical properties measurements, are summarized in this paper.
Date: October 1, 1997
Creator: Smith, D.L.; Natesan, K.; Park, J.H.; Mattas, R. & Reed, C.
Partner: UNT Libraries Government Documents Department

An Evaluation of Condition Monitoring Techniques for Low-Voltage Electric Cables

Description: Aging of systems and components in nuclear power plants is a well known occurrence that must be managed to ensure the continued safe operation of these plants. Much of the degradation due to aging is controlled through periodic maintenance and/or component replacement. However, there are components that do not receive periodic maintenance or monitoring once they are installed; electric cables are such a component. To provide a means of monitoring the condition of electric cables, research is ongoing to evaluate promising condition monitoring (CM) techniques that can be used in situ to monitor cable condition and predict remaining life. While several techniques are promising, each has limitations that must be considered in its application. This paper discusses the theory behind several of the promising cable CM techniques being studied, along with their effectiveness for monitoring aging degradation in typical cable insulation materials, such as cross-linked polyethylene and ethylene propylene rubber. Successes and limitations of each technique are also presented.
Date: July 23, 2000
Creator: Lofaro, Robert J.; Grove, Edward & Soo, Peter
Partner: UNT Libraries Government Documents Department

Summary report for ITER task - T68: MHD facility preparation for Li/V blanket option

Description: A key feasibility issue for the ITER Vanadium/Lithium breeding blanket is the question of insulator coatings. Design calculations show that an electrically insulating layer is necessary to maintain an acceptably low MHD pressure drop. To enable experimental investigations of the MHD performance of candidate insulator materials and the technology for putting them in place, the room-temperature ALEX (Argonne`s Liquid Metal EXperiment) NaK facility was upgraded to a 300{degrees}C lithium system. The objective of this upgrade was to modify the existing facility to the minimum extent necessary, consistent with providing a safe, flexible, and easy to operate MHD test facility which uses lithium at ITER-relevant temperatures, Hartmann numbers, and interaction parameters. The facility was designed to produce MHD pressure drop data, test section voltage distributions, and heat transfer data for mid-scale test sections and blanket mockups. The system design description for this lithium upgrade of the ALEX facility is given in this document.
Date: August 1, 1995
Creator: Reed, C.B.; Haglund, R.C. & Miller, M.E.
Partner: UNT Libraries Government Documents Department

Fabrication techniques for septum magnets at the APS.

Description: The design, construction, and installation of pulsed septum magnets for particle accelerators presents many challenges for the magnet engineer. Issues associated with magnet core structure design, component alignment, weldment design, and electrical insulation choices are among those requiring careful attention. The designs of the six septum magnets required for the APS facility have evolved since operation began in 1996. Improvements in the designs have provided better injection/extraction performance parameters and extended the machine reliability to meet the requirements of a world-class, third-generation synchrotron radiation facility. Details of the techniques used to address issues involved in producing septum magnets at the APS are described here to aid magnet engineers in the fabrication of future septum magnets.
Date: September 16, 2002
Creator: Jaski, M.; Thompson, K.; Kim, S.; Friedsam, H.; Toter, W. & Humbert, J.
Partner: UNT Libraries Government Documents Department

Central Solenoid Insert Technical Specification

Description: The US ITER Project Office (USIPO) is responsible for the ITER central solenoid (CS) contribution to the ITER project. The Central Solenoid Insert (CSI) project will allow ITER validation the appropriate lengths of the conductors to be used in the full-scale CS coils under relevant conditions. The ITER Program plans to build and test a CSI to verify the performance of the CS conductor. The CSI is a one-layer solenoid with an inner diameter of 1.48 m and a height of 4.45 m between electric terminal ends. The coil weight with the terminals is approximately 820 kg without insulation. The major goal of the CSI is to measure the temperature margin of the CS under the ITER direct current (DC) operating conditions, including determining sensitivity to load cycles. Performance of the joints, ramp rate sensitivity, and stability against thermal or electromagnetic disturbances, electrical insulation, losses, and instrumentation are addressed separately and therefore are not major goals in this project. However, losses and joint performance will be tested during the CSI testing campaign. The USIPO will build the CSI that will be tested at the Central Solenoid Model Coil (CSMC) Test Facility at the Japan Atomic Energy Agency (JAEA), Naka, Japan. The industrial vendors (the Suppliers) will report to the USIPO (the Company). All approvals to proceed will be issued by the Company, which in some cases, as specified in this document, will also require the approval of the ITER Organization. Responsibilities and obligations will be covered by respective contracts between the USIPO, called Company interchangeably, and the industrial Prime Contractors, called Suppliers. Different stages of work may be performed by more than one Prime Contractor, as described in this specification. Technical requirements of the contract between the Company and the Prime Contractor will be covered by the Fabrication Specifications developed ...
Date: September 1, 2011
Creator: Martovetsky, Nicolai N & Smirnov, Alexandre
Partner: UNT Libraries Government Documents Department