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Advanced concepts for a 1200 kV shunt reactor. First quarterly progress report, 28 September 1978--31 December 1978

Description: The objective of this program is to explore new concepts for inductive shunt reactor designs for integration into a 1200 kV gas-insulated substation. The most promising design must exhibit low dimensional profile with reduced weight, lower losses, lower noise level and smaller amplitude of vibration when compared with the units of equivalent rating built with the present day technology. The planning and organization of this research program are described.
Date: January 1, 1978
Partner: UNT Libraries Government Documents Department

Homeowner Best Practices Guide for Residential Retrofits

Description: This best practices guide for HV AC system retrofits is aimed at homeowners who want guidance on upgrading their heating, cooling and ventilation (HVAC) systems and integrating these upgrades with other changes to their home. It has been developed around the idea of having packages of changes to the building HV AC system and building envelope that are climate and house construction dependent. These packages include materials procedures and equipment, and are designed to remove some of the guesswork when selecting a builder, contractor, or installer. The packages are not meant to be taken as rigid requirements - instead they are systems engineered guidelines that form the basis for energy efficient retrofits. Similar approaches have been taken previously for new construction, where a systems engineering approach has been used to develop extremely energy-efficient homes that are comfortable safe and durable, and often cost less than standard construction. This approach is best epitomized by the Building America program, whose partners have built thousands of residences throughout the U.S. using these principles. The differences between retrofitting and new construction tend to limit the changes one can make to a building, so these packages rely on relatively simple and non-intrusive technologies and techniques. The retrofits also focus on changes to a building that will give many years of service to the occupants. Another key aspect of these best practices is that we need to know how a house is working so that we know what parts have the potential for improvement. To do this we have put together a set of simple tests that a homeowner can perform on their own together with checklists and questionnaires. The measured test results, observations and homeowner answers to questions are used to direct us towards the best retrofits applicable to each individual house. The retrofits will ...
Date: September 1, 2005
Creator: Walker, Iain S.
Partner: UNT Libraries Government Documents Department

Evaluation of advanced technologies for power transformers. Final report. Part I, November 1976-March 1979

Description: The high insulating strength of certain gases, such as sulfur hexafluoride, when used at high pressure, suggests that there may be advantages to compressed gases as the insulating fluid in power transformers. However, simply exchanging the oil for compressed gas in an otherwise conventional transformer design will not yield a significant overall advantage. Compressed gases present the engineer with properties which are quite different from mineral oil. If gases are to be used as the major insulating fluid in power transformers, then virtually all aspects of the insulation and cooling of the apparatus must be reconsidered, affording an opportunity to introduce new design concepts, new materials, and new construction techniques. In this program, the feasibility of using the following principal design concepts has been explored: sheet conductors for the windings; a system of sealed, self-contained, annular cooling ducts containing circulating cooling fluid to cool the windings; polymer film for turn-to-turn insulation; and compressed gas insulation. Experimental and analytical studies, described in this report, indicate that the sheet-wound, compressed-gas-insulated design should result in power transformers of significantly smaller size and weight when compared with oil-filled units of equivalent rating. These advanced technologies offer the opportunity for the design of more efficient power transformers.
Date: June 1, 1980
Partner: UNT Libraries Government Documents Department

Single-phase ac losses in prototype HTS conductors for superconducting power transmission lines

Description: The authors report single-phase ac loss measurements on 8, 4, and 3-layer, multi-strand, HTS prototype conductors for power transmission lines. They use both calorimetric and electrical techniques. The agreement between the two techniques suggests that the interlayer current distribution in one-meter long conductors are representative of those in long conductors. The losses for the 8 and 4-layer conductors are in rough agreement, with the 8-layer losses being somewhat lower. The 3-layer conductor losses are substantially higher--probably due to unbalanced azimuthal currents for this configuration.
Date: December 1, 1998
Creator: Daney, D.E.; Maley, M.P.; Boenig, H.J.; Willis, J.O.; Coulter, J.Y.; Gherardi, L. et al.
Partner: UNT Libraries Government Documents Department

SunSine300 AC module. Annual report, July 25, 1995--December 31, 1996

Description: Under Photovoltaic Manufacturing Technology (PVMaT) 4A1, Ascension Technology (AT) is developing the SunSine300 AC PV module. AT`s goals in this project are to meet Underwriters Laboratory (UL) 1741 requirements, obtain Federal Communications Commission (FCC) Class B verification, complete the AC module system design and development, advance the inverter design, design for manufacture, design for reliability, design for serviceability, and demonstrate commercialization through production and sale of about 100 units. To meet these goals, AT corrected a number of deficiencies identified by UL`s preliminary investigation before proceeding to the full UL investigation; a SunSine300 prototype was tested and found to comply with FCC Class B requirements; AT designed a complete line of balance-of-systems hardware for the SunSine 300; AT`s design and performance advancements include accomplishing a total harmonic distortion drop from 5% to 2%, devising a method to eliminate false detection of zero crossings that could damage the inverter, improving the anti-islanding with the addition of AT`s proprietary ZEBRA technique, and redesigning the enclosure for thermal performance, manufacturability, and UL and FCC approval; performing extensive testing in Phase 2 to discover failure modes and susceptibility to aging; and designing the SunSine300 to be easily and safely serviced. 3 figs., 3 tabs.
Date: August 1, 1997
Creator: Russell, M.C. & Handleman, C.K.P.
Partner: UNT Libraries Government Documents Department

Development and advances in conventional high power RF systems

Description: The development of rf systems capable of producing high peak power (hundreds of megawatts) at relatively short pulse lengths (0.1--5 microseconds) is currently being driven mainly by the requirements of future high energy linear colliders, although there may be applications to industrial, medical and research linacs as well. The production of high peak power rf typically involves four basic elements: a power supply to convert ac from the ``wall plug`` to dc; a modulator, or some sort of switching element, to produce pulsed dc power; an rf source to convert the pulsed dc to pulsed rf power; and possibly an rf pulse compression system to further enhance the peak rf power. Each element in this rf chain from wall plug to accelerating structure must perform with high efficiency in a linear collider application, such that the overall system efficiency is 30% or more. Basic design concepts are discussed for klystrons, modulators and rf pulse compression systems, and their present design status is summarized for applications to proposed linear colliders.
Date: June 1, 1995
Creator: Wilson, P.B.
Partner: UNT Libraries Government Documents Department

Multilevel converters for power system applications

Description: Multilevel converters are emerging as a new breed of power converter options for power system applications. These converters are most suitable for high voltage high power applications because they connect devices in series without the need for component matching. One of the major limitations of the multilevel converters is the voltage unbalance between different levels. To avoid voltage unbalance between different levels, several techniques have been proposed for different applications. Excluding magnetic-coupled converters, this paper introduces three multilevel voltage source converters: (1) diode-clamp, (2) flying-capacitors, and (3) cascaded inverters with separate dc sources. The operation principle, features, constraints, and potential applications of these converters will be discussed.
Date: September 1, 1995
Creator: Lai, J.S.; Stovall, J.P. & Peng, F.Z.
Partner: UNT Libraries Government Documents Department

ac transmission line field measurements

Description: The concern in recent years over the environmental effects of electric and magnetic fields from high voltage transmission lines has also focused attention on the accuracy of measurements of these fields. Electric field meters are discussed in terms of theory of operation, parameters affecting performance, meter performance under field and laboratory conditions, and calibration procedures. The performance and calibration of magnetic field meters is described. (LCL)
Date: November 1, 1977
Creator: Kotter, F.R. & Misakian, M.
Partner: UNT Libraries Government Documents Department

Superconducting fault current limiter. First quarterly technical progress report, August 8-November 7, 1978. [230 kV]

Description: The purpose of this project is to investigate the suitability of using a superconducting fault current limiter (SCFCL) in conjunction with other superconducting apparatus or transmission lines. Literature search, consultation, analysis and experimentation are to be carried out to derive a set of operational parameters for a SCFCL and to answer key questions as to the feasibility of a superconducting element to meet these performance objectives. During the first quarter year of effort, substantial progress has been made on several of these program tasks. A comprehensive search of the literature on SCFCL devices and applications was initiated; the references which were obtained to date are evaluated within a framework into which additional references can be added as they are received. Consultation with key researchers has occurred to supplement and update the literature search. Device analyses have also been started in order to determine to what extent the various proposed SCFCL devices meet the requirements of the power system.
Date: January 1, 1979
Partner: UNT Libraries Government Documents Department

Static reactive power compensators for high-voltage power systems. Final report

Description: A study conducted to summarize the role of static reactive power compensators for high voltage power system applications is described. This information should be useful to the utility system planning engineer in applying static var systems (SVS) to high voltage as (HVAC) systems. The static var system is defined as a form of reactive power compensator. The general need for reactive power compensation in HVAC systems is discussed, and the static var system is compared to other devices utilized to provide reactive power compensation. Examples are presented of applying SVS for specific functions, such as the prevention of voltage collapse. The operating principles of commercially available SVS's are discussed in detail. The perormance and active power loss characteristics of SVS types are compared.
Date: April 1, 1981
Partner: UNT Libraries Government Documents Department

Study to investigate the basic switching impulse insulation level requirements for a 1200 kV CGIT cable system

Description: A study was performed to determine the switching surge voltages a prototype 1200 kV CGIT cable may be exposed to under service conditions. The results of this study were used to establish the system's basic switching impulse insulation level requirements. An investigation was made of a suitable CGIT model to be employed for use on the Westinghouse transient network analyzer. The model chosen was applicable for the cable when its sheaths are solidly grounded. This model was employed for each of the four cable lengths investigated. Cable lengths of 600 ft, 2 miles, 10 miles and 50 miles were investigated in four general system configurations, in all 47 systems were studied.
Date: July 1, 1979
Creator: Pfleiderer, R.
Partner: UNT Libraries Government Documents Department

Application of superconducting coils to VAR control in electric power systems: a proposal

Description: During the last eight years, static VAR-control systems with thyristor-controlled, room-temperature reactors have been used in electrical systems for voltage control and system stabilization. In this proposal, we describe a new static VAR-control system that uses an asymmetrically controlled Graetz bridge and a superconducting dc coil. Preliminary studies indicate that the proposed system will have lower overall losses and that its capital cost and electrical characteristics are comparable to those of a conventional system. Three- and four-year programs for developing the electronic circuitry and superconducting coils for VAR control, culminating in the installation and testing of an approx. 40-MVAR system, are proposed.
Date: November 1, 1979
Creator: Boenig, H.J. & Hassenzahl, W.V.
Partner: UNT Libraries Government Documents Department

Evaluation of higher distribution and/or utilization voltages. First interim report (December 1978): literature search and problem definition

Description: A literature search has been conducted on the economics and technical problems associated with the use of higher voltages in both the primary distribution and secondary utilization systems. After a literature review and evaluation, an assessment of the state-of-the-art with regard to high voltage has been made and is presented for the primary and secondary distribution systems, end use elements, and economics and system analysis or optimization. An annotated bibliography is provided for each of the three categories. A comprehensive list of potential advantages and disadvantages of higher primary distribution and utilization voltages has also been prepared and is presented.
Date: April 1, 1981
Partner: UNT Libraries Government Documents Department

Evaluation of higher distribution and/or utilization voltages. Fourth interim report (August 1980): assessment of optimum distribution configuration

Description: This interim report provides documentation on the fourth task, Assessment of Optimum Distribution Configuration, of DOE Contract No. ET-78-C-01-2866, Evaluation of Higher Distribution and/or Utilization Voltages. The work performed under this task includes the development of a computer model for assessment of life cycle costs for the distribution and utilization systems, the development of an optimization algorithm to enable distribution system configuration optimization and a net energy analysis to determine potential net energy savings. Input data for this task derive from Task 3. The major output of this task is a documented computer code.
Date: April 1, 1981
Partner: UNT Libraries Government Documents Department

Electrical and mechanical design criteria for EHV and UHV: overhead transmission lines

Description: The results are presented of a program devoted to the selection of electrical and mechanical design criteria and parameters for overhead power transmission lines for ac systems rated at from 345 to 1100 kV and for dc systems rated at from 600 to 1200 kV. Information is included on the environmental effects, i.e., audible noise and electric fields, of the lines, mechanical and economic requirements, safety, failures, grounding, and lightning protection. (LCL)
Date: June 1, 1980
Partner: UNT Libraries Government Documents Department

New codes and standards for utility - interconnection of AC PV modules

Description: Photovoltaic (PV) modules that provide only ac power give new dimensions to the use of, and utility interface of, PV systems because all of the dc issues are virtually eliminated. These AC PV modules offer the important advantage that customers may now purchase a PV system without hiring a design engineer. A qualified electrician will be able to install a complete PV system that performs as expected and meets local electrical codes. Simple installations of additional AC PV modules will be possible once the proper branch circuit wiring and protection have been installed. Codes and standards are currently being written to address the utility-interconnect issues for AC PV modules and other interactive inverters. An industry-supported Task Group has recently written and submitted proposals for changes to bring Article 690 of the 1999 National Electrical Code{reg_sign} (NEC{reg_sign}) up to the state-of-the-art for PV devices such as AC PV modules. This paper summarizes the proposed code changes and standards related to the evolving AC PV module technology in the United States. Topics such as the need for dedicated branch circuits for AC PV modules in residential applications are discussed and analyzed. Requirements for limiting the number of AC modules on a branch circuit and the listing requirements that make safe installations are discussed. Coordination of all standards activities for AC module installations, the building-integrated perspectives, and utility-interface issues is discussed.
Date: October 1, 1997
Creator: Bower, W.
Partner: UNT Libraries Government Documents Department

Commercialization of PV-powered pumping systems for use in utility PV service programs. Final report

Description: The project described in this report was a commercialization effort focused on cost-effective remote water pumping systems for use in utility-based photovoltaic (PV) service programs. The project combined a commercialization strategy tailored specifically for electric utilities with the development of a PV-powered pumping system that operates conventional ac pumps rather than relying on the more expensive and less reliable PV pumps on the market. By combining these two attributes, a project goal was established of creating sustained utility purchases of 250 PV-powered water pumping systems per year. The results of each of these tasks are presented in two parts contained in this Final Summary Report. The first part summarizes the results of the Photovoltaic Services Network (PSN) as a new business venture, while the second part summarizes the results of the Golden Photon system installations. Specifically, results and photographs from each of the system installations are presented in this latter part.
Date: March 1, 1997
Partner: UNT Libraries Government Documents Department

TRIAC/SCR proportional control circuit

Description: A power controller device which uses a voltage-to-frequency converter in conjunction with a zero crossing detector to linearly and proportionally control AC power being supplied to a load. The output of the voltage to frequency converter controls the reset input of a R-S flip flop, while an 0 crossing detector controls the set input. The output of the flip flop triggers a monostable multivibrator controlling the SCR or TRIAC firing circuit connected to the load. Logic gates prevent the direct triggering of the multivibrator in the rare instance where the reset and set inputs of the flip flop are in coincidence. The control circuit can be supplemented with a control loop, providing compensation for line voltage variations.
Date: December 1, 1997
Creator: Hughes, Wallace J.
Partner: UNT Libraries Government Documents Department

Model for the ready definition and approximate comparison of alternative high voltage transmission systems. Phases II and III. Application to electric systems within the contiguous United States. [800 and 1200 kV; 400, 600, and 800 kV dc]

Description: Research on power delivery alternatives is reported. The first phase of this work was to develop a model of overhead transmission systems in the range of 362 to 1200 kV ac, and +-400 to +-800 kV dc. Such systems included transmission from generation to load and inter-connection of two large integrated systems, with and without the existence of an underlying lower voltage network in either case. This phase has been completed. The second and third phases involved application of the model to electric systems within selected regions of the US, and the entire US, respectively, dealing with real situations and including projected expansion to year 1987. The potential benefits and costs of using higher than existing transmission voltages were to be evaluated on this basis. Additionally, the most advantageous new voltage was to be determined taking into account direct and indirect benefits and costs. The results of the second and third phases are presented.
Date: August 1, 1979
Partner: UNT Libraries Government Documents Department

Comments about the use of a Zig-Zag transformer to reduce the neutral current created by unbalanced nonlinear loads

Description: The subject of AC line currents with high harmonic content and the potential for overloaded neutral wires caused by the non-linear loading of electronic power supplies has become one of the most popular and at the same time a very complex topic among electrical engineers. Different solutions are offered for this problem. Some examples are specially designed K-rated AC distribution transformers, delta connected primary windings, and L-C tuned filters. All of the above methods have some limitations. For instance, a K-rated transformer does not eliminate harmonics, but transmits them into the feeder. Neutral currents that flow from various loads to the K-rated transformer are still very high. These K-rated transformers are more expensive and are larger in physical size than conventional transformers. The delta connected primary of a power distribution transformer can only eliminate triplen harmonics for balanced loads. Neutral currents caused by the loads are not eliminated. The primary side circuit breaker may also not protect a transformer against overcurrents because the circuit breaker will not see the triplen harmonic current that is circulating in the primary of the transformer. L-C filters can create undesirable resonances, which will lead to an increase in harmonic currents. Another solution is to use a number of small Zig-Zag transformers to reduce the neutral current. This is attractive for the following reasons: relatively low cost, simplicity, ease of installation on existing distribution systems, ability to keep neutral currents local thus eliminating the need for larger neutral wires, and the ability to improve the fundamental load current balance as well.
Date: September 1, 1993
Creator: Beverly, L.; Hance, R.; Kristalinski, A. & Visser, A.
Partner: UNT Libraries Government Documents Department

Elimination of particle effects in SF/sub 6/ insulated transmission systems. First quarterly report

Description: The purpose of this program is to develop methods and equipment to eliminate the adverse effect of particle contamination in SF/sub 6/-insulated transmission (CGIT) systems, so that the excellent dielectric properties of SF/sub 6/ can be fully exploited. Presently, CGIT systems are operated at about 10% of the dielectric strength capability of the SF/sub 6/ gas. The program includes theoretical and experimental evaluation of concepts, optimization and verification studies in CGIT systems, and reliability analysis, documentation of designs and economic analysis. Progress is now being made on evaluating alternative conductor and sheath designs to minimize the effect of particles. Materials for solid insulation is being investigated for the same purpose; the effort is presently concentrated on obtaining reliable quantitative measurement techniques of electrostatic properties. Computer calculation of particle trap configurations are being made to determine the optimum trap configurations. A novel particle trapping technique is being using adhesive materials. Manufacture and field control technique studies has commenced with a study of mechanical vibration techniques. An experimental test chamber consisting of a 9 m (30 foot) long 145 kV bus has been designed. This system will be used in testing of particle control concepts and in migration and optimization studies.
Date: January 1, 1979
Creator: Dale, S.J.
Partner: UNT Libraries Government Documents Department

Field validation of cable monitoring and rating system (CMARS) laboratory model. Semi-annual report, 1 May 1979-31 December 1979

Description: One year of research on validating the performance of the Cable Monitoring and Rating System (CMARS) is reported. The performance testing was conducted on underground 230-kV and 345-kV pipe type cable circuits owned by the New Jersey Public Service Electric and Gas Co. Laser temperature monitoring systems and a data acquisition system were installed. Software installation and development is discussed. The CMARS testing program is described. (LCL)
Date: January 1, 1980
Creator: Englehardt, J.; Harris, H.; Kasny, E.; Orifice, D.; Patton, R. & Sottovia, P.
Partner: UNT Libraries Government Documents Department

Field validation of cable monitoring and rating system (CMARS) laboratory model. First semi-annual report, 1 November 1978-30 April 1979

Description: The goal of this project is to quantitatively validate the Cable Monitoring and Rating System (CMARS) software and associated hardware as applied to commercially operating underground transmission systems which are representative of the bulk of this type of system used in the USA. In the course of the project, it is expected that improvements and refinements of the CMARS will occur resulting in improved accuracy, flexibility and predictive capability for CMARS. The circuits to be utilized are equipped with extensive monitoring facilities, which will allow the determination of CMARS accuracy. In addition, recommendations will be made regarding accuracy vs. cost tradeoffs as a function of the amount and complexity of data which might be available on or retrofitted to existing systems, or considered for future systems. Information displays will be optimized by discussions with system operators, transmission planners and underground transmission engineering groups. Finally, hardware installation problems for sensor equipment as well as data acquisition equipment will be readily identified. At the completion of the proposed work, specifications for CMARS software and hardware, and all associated sensor, data acquisition and communications equipment will be available to the industry. The first semi-annual report on the project is presented.
Date: January 1, 1979
Creator: Englehardt, J.; O'Neill, D.; Orifice, D. & Patton, R.
Partner: UNT Libraries Government Documents Department