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Propulsion and stabilization system for magnetically levitated vehicles

Description: A propulsion and stabilization system for an inductive repulsion type magnetically levitated vehicle which is propelled and stabilized by a system which includes propulsion windings mounted above and parallel to vehicle-borne suspension magnets. A linear synchronous motor is part of the vehicle guideway and is mounted above and parallel to superconducting magnets attached to the magnetically levitated vehicle.
Date: December 31, 1992
Creator: Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Magnetic levitation configuration incorporating levitation, guidance and linear synchronous motor

Description: A propulsion and suspension system for an inductive repulsion type magnetically levitated vehicle which is propelled and suspended by a system which includes propulsion windings which form a linear synchronous motor and conductive guideways, adjacent to the propulsion windings, where both combine to partially encircling the vehicle-borne superconducting magnets. A three phase power source is used with the linear synchronous motor to produce a traveling magnetic wave which in conjunction with the magnets propel the vehicle. The conductive guideway combines with the superconducting magnets to provide for vehicle leviation.
Date: December 31, 1992
Creator: Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Maglev system design considerations

Description: Although efforts are now being made to develop magnetic levitation technologies in the United States, they have been underway for two decades in Germany and Japan. The characteristics of maglev systems being considered for implementation in the United States are speculative. A conference was held at Argonne National Laboratory on November 28--29, 1990, to discuss these characteristics and their implications for the design requirements of operational systems. This paper reviews some of the factors considered during that conference.
Date: January 1, 1991
Creator: Coffey, H.T.
Partner: UNT Libraries Government Documents Department

Transportation in the twenty-first century

Description: New energy-efficient and environmentally-sound magnetically levitated (maglev) transportation systems are being developed that have the potential to supplement and extend the intercity portion of our transportation system, and to alleviate part of the commuter congestion on our highways. Prototype passenger-carrying maglev vehicles are now operating in Japan and Germany. The capabilities of these systems, described in science fiction over two decades ago, are no longer speculative. They will be capable of transporting 100--150 passengers per vehicles or 1500 passengers per train at speeds of 250--350 mph. While performing many of the same functions of short-haul aircraft, these electrically powered vehicles: do not emit pollutants along the route; use about 1/3 the energy per passenger mile of modern aircraft; do not contact the guideway and therefore minimize maintenance; are silent except for the noise of air passing over the body. This paper assesses current maglev technology. 7 refs., 5 figs.
Date: December 1, 1991
Creator: Coffey, H. T.
Partner: UNT Libraries Government Documents Department

US maglev: Status and opportunities

Description: Recognizing the development of maglev systems in Germany and Japan, and the growing congestion, air pollution and energy consumption resulting from our current transportation system, the United States, in 1990, embarked on a program to evaluate the potential usefulness of these systems in the US. In this paper, the utility of maglev systems in alleviating some of these problems, progress in the current program, and opportunities for participation by the superconductivity and cryogenic communities are discussed.
Date: September 1, 1992
Creator: Coffey, H. T.
Partner: UNT Libraries Government Documents Department

US maglev: Status and opportunities

Description: Recognizing the development of maglev systems in Germany and Japan, and the growing congestion, air pollution and energy consumption resulting from our current transportation system, the United States, in 1990, embarked on a program to evaluate the potential usefulness of these systems in the US. In this paper, the utility of maglev systems in alleviating some of these problems, progress in the current program, and opportunities for participation by the superconductivity and cryogenic communities are discussed.
Date: January 1, 1992
Creator: Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Transportation in the twenty-first century

Description: New energy-efficient and environmentally-sound magnetically levitated (maglev) transportation systems are being developed that have the potential to supplement and extend the intercity portion of our transportation system, and to alleviate part of the commuter congestion on our highways. Prototype passenger-carrying maglev vehicles are now operating in Japan and Germany. The capabilities of these systems, described in science fiction over two decades ago, are no longer speculative. They will be capable of transporting 100--150 passengers per vehicles or 1500 passengers per train at speeds of 250--350 mph. While performing many of the same functions of short-haul aircraft, these electrically powered vehicles: do not emit pollutants along the route; use about 1/3 the energy per passenger mile of modern aircraft; do not contact the guideway and therefore minimize maintenance; are silent except for the noise of air passing over the body. This paper assesses current maglev technology. 7 refs., 5 figs.
Date: January 1, 1991
Creator: Coffey, H.T.
Partner: UNT Libraries Government Documents Department

Survey of foreign maglev systems

Description: Magnetic levitation (maglev) transportation systems represent an innovative technology that promises to provide pollution-free, contact-free, high-speed ground transportation for the twenty-first century. Great interest in maglev systems has been developing in the United States over the past two years under the auspices of the US National Maglev Initiative. The objective of the survey presented in this report is to provide the US maglev community with information on various maglev concepts that were developed in foreign countries over the past two decades. The main maglev systems included in the survey are the German Transrapid series and the M-Bahn, the Japanese HSST and MLU series, and the British Birmingham. Each maglev system is introduced and discussed according to its type, historical development, unique features, current status, and future prospects. Advantages and disadvantages of each system are briefly noted.
Date: July 1, 1992
Creator: He, J.L.; Rote, D.M. & Coffey, H.T.
Partner: UNT Libraries Government Documents Department

Vehicle/guideway interaction for high speed vehicles on flexible guideway

Description: Dynamic interactions between vehicles and guideways of a high speed ground transportation system based on magnetically levitated vehicles are studied with an emphasis on the effects of vehicle and guideway parameters. Two dynamic models for vehicles are presented: first, the vehicle is considered as a moving force traveling on a simply-supported single-span or two-span beams with various speeds; and second, the vehicle is considered as a one dimensional model with two-degrees-of-freedom which represents the primary and secondary suspensions of a vehicle with lumped masses, linear springs, and dampings. The Bernoulli-Euler beam equation is used to model the characteristics of a flexible guideway, and the guideway synthesis is based on a model analysis method. A series of analysis has been performed to understand the response characteristics under different loading conditions and provide some benchmark data for verifications of other comprehensive computer programs and some basic design guideline for maglev systems. 16 refs.
Date: January 1, 1992
Creator: Cai, Y.; Chen, S.S.; Rote, D.M. & Coffey, H.T.
Partner: UNT Libraries Government Documents Department

Survey of foreign maglev systems

Description: Magnetic levitation (maglev) transportation systems represent an innovative technology that promises to provide pollution-free, contact-free, high-speed ground transportation for the twenty-first century. Great interest in maglev systems has been developing in the United States over the past two years under the auspices of the US National Maglev Initiative. The objective of the survey presented in this report is to provide the US maglev community with information on various maglev concepts that were developed in foreign countries over the past two decades. The main maglev systems included in the survey are the German Transrapid series and the M-Bahn, the Japanese HSST and MLU series, and the British Birmingham. Each maglev system is introduced and discussed according to its type, historical development, unique features, current status, and future prospects. Advantages and disadvantages of each system are briefly noted.
Date: July 1, 1992
Creator: He, J. L.; Rote, D. M. & Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Vehicle/guideway interaction for high speed vehicles on flexible guideway

Description: Dynamic interactions between vehicles and guideways of a high speed ground transportation system based on magnetically levitated vehicles are studied with an emphasis on the effects of vehicle and guideway parameters. Two dynamic models for vehicles are presented: first, the vehicle is considered as a moving force traveling on a simply-supported single-span or two-span beams with various speeds; and second, the vehicle is considered as a one dimensional model with two-degrees-of-freedom which represents the primary and secondary suspensions of a vehicle with lumped masses, linear springs, and dampings. The Bernoulli-Euler beam equation is used to model the characteristics of a flexible guideway, and the guideway synthesis is based on a model analysis method. A series of analysis has been performed to understand the response characteristics under different loading conditions and provide some benchmark data for verifications of other comprehensive computer programs and some basic design guideline for maglev systems. 16 refs.
Date: May 1, 1992
Creator: Cai, Y.; Chen, S. S.; Rote, D. M. & Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Improved high speed maglev design

Description: This report discusses a propulsion and stabilization system for an inductive repulsion type magnetically levitated vehicle which is propelled and suspended by a system which includes dividing the superconducting magnets into two types: a strong field magnet which is located vertically below the vehicle for propulsion and guidance and a weak field superconducting magnet located at the ends of the vehicle for levitation and added guidance. Several proposed embodiments exist for the placement of the magnetic field shielding: locating the shielding on the vehicle, locating the shielding on the guideway, and locating the shielding on the guideway and adding shielding to the vertical undercarriage. In addition, the separation between the be vehicle and the guideway can be controlled to reduce the exposure of the passenger cabin to magnetic fields.
Date: January 1, 1992
Creator: Rote, D. M.; He, Jianliang & Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Dual-keel electrodynamic Maglev system

Description: This paper introduces a new concept for an electrodynamic-suspension maglev system that has a dual-keel arrangement. Each keel consists of a row of superconducting magnets aboard the vehicle. The keels move in troughs in the guideway that are each lined with pairs of figure-eight-shaped null-flux coils. Each pair of null-flux coils is cross-connected to produce null-flux suspension and guidance force. The cross-connected figure-eight null-flux coils in each trough are also energized by a three-phase power supply to produce propulsive force. Preliminary analysis shows that the new system has many advantages over other EDS systems in terms of system performance and dynamic stability.
Date: December 31, 1995
Creator: He, Jianliang; Rote, D.M.; Wang, Zian & Coffey, H.T.
Partner: UNT Libraries Government Documents Department

Maglev vehicles and superconductor technology: Integration of high-speed ground transportation into the air travel system

Description: This study was undertaken to (1) evaluate the potential contribution of high-temperature superconductors (HTSCs) to the technical and economic feasibility of magnetically levitated (maglev) vehicles, (2) determine the status of maglev transportation research in the United States and abroad, (3) identify the likelihood of a significant transportation market for high-speed maglev vehicles, and (4) provide a preliminary assessment of the potential energy and economic benefits of maglev systems. HTSCs should be considered as an enhancing, rather than an enabling, development for maglev transportation because they should improve reliability and reduce energy and maintenance costs. Superconducting maglev transportation technologies were developed in the United States in the late 1960s and early 1970s. Federal support was withdrawn in 1975, but major maglev transportation programs were continued in Japan and West Germany, where full-scale prototypes now carry passengers at speeds of 250 mi/h in demonstration runs. Maglev systems are generally viewed as very-high-speed train systems, but this study shows that the potential market for maglev technology as a train system, e.g., from one downtown to another, is limited. Rather, aircraft and maglev vehicles should be seen as complementing rather than competing transportation systems. If maglev systems were integrated into major hub airport operations, they could become economical in many relatively high-density US corridors. Air traffic congestion and associated noise and pollutant emissions around airports would also be reduced. 68 refs., 26 figs., 16 tabs.
Date: April 1, 1989
Creator: Johnson, L.R.; Rote, D.M.; Hull, J.R.; Coffey, H.T.; Daley, J.G. & Giese, R.F.
Partner: UNT Libraries Government Documents Department

Dynamics, stability, and control of maglev systems

Description: The dynamic response of maglev systems is important in several respects: Safety and ride quality, guideway design, and system costs. The dynamic response of vehicles is the key element in the determination of ride quality, and vehicle stability is one of the important elements relative to safety. To design a proper guideway that provides acceptable ride quality in the stable region, the vehicle dynamics must be understood. The trade-off between guideway smoothness and the levitation and control systems must be considered if maglev systems are to be economically feasible. This paper is a summary of our previous work on dynamics, stability and control of maglev systems. First of all, the importance of dynamics of vehicle/guideway of maglev systems is discussed. Emphasis is placed on the modeling vehicle/guideway interactions of maglev systems with a multicar, or multiload vehicle traversing on a single or double-span flexible guideway. Coupled effects of vehicle/guideway interactions in wide range of vehicle speeds with various vehicle and guideway parameters for maglev systems are investigated. Secondly, the alternative control designs of maglev vehicle suspension systems are investigated in this study to achieve safe, stable operation and acceptable ride comfort requires some form of vehicle motion control. Active and semi-active control law designs are introduced into primary and secondary suspensions of maglev vehicles. Finally, this paper discusses the stability of maglev systems based on experimental data, scoping calculations, and simple mathematical models. Divergence and flutter are obtained for coupled vibration of a three-degree-of-freedom maglev vehicle on a guideway consisting of double L-shaped aluminum segments. The theory and analysis developed in this study provides basic stability characteristics and identifies future research needs for maglev systems.
Date: January 1, 1993
Creator: Cai, Y.; Chen, S.S.; Rote, D. M. & Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Dynamics, stability, and control of maglev systems

Description: The dynamic response of maglev systems is important in several respects: Safety and ride quality, guideway design, and system costs. The dynamic response of vehicles is the key element in the determination of ride quality, and vehicle stability is one of the important elements relative to safety. To design a proper guideway that provides acceptable ride quality in the stable region, the vehicle dynamics must be understood. The trade-off between guideway smoothness and the levitation and control systems must be considered if maglev systems are to be economically feasible. This paper is a summary of our previous work on dynamics, stability and control of maglev systems. First of all, the importance of dynamics of vehicle/guideway of maglev systems is discussed. Emphasis is placed on the modeling vehicle/guideway interactions of maglev systems with a multicar, or multiload vehicle traversing on a single or double-span flexible guideway. Coupled effects of vehicle/guideway interactions in wide range of vehicle speeds with various vehicle and guideway parameters for maglev systems are investigated. Secondly, the alternative control designs of maglev vehicle suspension systems are investigated in this study to achieve safe, stable operation and acceptable ride comfort requires some form of vehicle motion control. Active and semi-active control law designs are introduced into primary and secondary suspensions of maglev vehicles. Finally, this paper discusses the stability of maglev systems based on experimental data, scoping calculations, and simple mathematical models. Divergence and flutter are obtained for coupled vibration of a three-degree-of-freedom maglev vehicle on a guideway consisting of double L-shaped aluminum segments. The theory and analysis developed in this study provides basic stability characteristics and identifies future research needs for maglev systems.
Date: June 1, 1993
Creator: Cai, Y.; Chen, S. S.; Rote, D. M. & Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Study of Japanese electrodynamic-suspension maglev systems

Description: This report presents the results of a study of the Japanese MLU magnetic-levitation (maglev) system. The development of the MLU system is reviewed, and the dynamic circuit model then is introduced and applied to the figure-eight-shaped null-flux coil suspension system. Three different types of figure-eight-shaped null-flux suspension systems are discussed in detail: (1) the figure-eight-shaped null-flux coil suspension system without cross-connection; (2) the combined suspension and guidance system; and (3) the combined propulsion, levitation, and guidance system. The electrodynamic-suspension maglev systems developed in Japan seem to be very promising and could result in a commercial application in the near future.
Date: April 1, 1994
Creator: He, J. L.; Rote, D. M. & Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Electrodynamic forces of the cross-connected figure-eight null-flux coil suspension system

Description: This paper analyzes the cross-connected figure-eight null-flux coil suspension system for maglev vehicles on the basis of dynamic circuit theory. The equivalent circuits and general magnetic force expressions for the system are developed. Simple analytical formulas for the magnetic force partitions on the basis of harmonic approximation are presented, and numerical results are also included.
Date: June 1, 1993
Creator: He, J. L.; Rote, D. M. & Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Vehicle/guideway interaction and ride comfort in maglev systems

Description: The importance of vehicle/guideway dynamics in maglev systems is discussed. The particular interest associated with modeling vehicle guide-way interactions and explaining response characteristics of maglev systems for a multicar, multiload vehicle traversing on a single- or double-span flexible guideway are considered, with an emphasis on vehicle/guideway coupling effects, comparison of concentrated and distributed loads, and ride comfort. Coupled effects of vehicle/guideway interactions over a wide range of vehicle speeds with various vehicle and guideway parameters are investigated, and appropriate critical vehicle speeds or crossing frequencies are identified.
Date: October 1, 1993
Creator: Cai, Y.; Chen, S. S.; Rote, D. M. & Coffey, H. T.
Partner: UNT Libraries Government Documents Department

Performance analysis of the combined EDS maglev propulsion, levitation, and guidance system

Description: An analysis of the Japanese maglev system which uses only one set of coils in the guideway for combined levitation, propulsion, and guidance functions is presented in this paper. This preliminary study, using the dynamic circuit approach, indicates that the system is very promising.
Date: October 1, 1993
Creator: He, J. L.; Coffey, H. T. & Rote, D. M.
Partner: UNT Libraries Government Documents Department

Publications on maglev technologies

Description: Magnetically levitated passenger-transportation vehicles, using attractive and repulsive magnetic forces, are currently in the development or prototype-revenue stages in Japan and Germany. The basic principles of these technologies have been understood for several decades, but their practical applications awaited advances in high-power electronic devices, modern controls, superconducting magnets, and improvements in our transportation infrastructures. A considerable amount of work was devoted to magnetic-levitation (maglev) transportation system in the late 1960s and the 1970s. Detailed development was sustained primarily in Germany and Japan. This listing of publications was begun as the initial phase of a design study for a maglev development facility sponsored by the State of Illinois. The listing has been continually updated under programs sponsored by the Federal Railroad Administration and the US Army Corps of Engineers. In 1991, the National Maglev Initiative issued 27 contracts for the study of technical issues related to maglev and four contracts for the definition of maglev systems. In December 1991, the Intermodal Surface Transportation Efficiency Act was enacted, mandating the development of a US-designed maglev system in a six-year period. This listing is offered as an aid to those working on these projects, to help them locate technical papers on relevant technologies. The design and installation of a maglev transportation system will require the efforts of workers in many disciplines, from electronics to economics to safety. Accordingly, the references have been grouped in 14 different sections to expedite review of the listing. In many case, the references are annotated to indicate the general content of the papers. Abstracts are not available. A list of information services from which the listed documents might be obtained and an author index are provided.
Date: December 1, 1991
Creator: He, J.L.; Coffey, H.T.; Rote, D.M. & Wang, Z.
Partner: UNT Libraries Government Documents Department

Dual-keel electrodynamic maglev system

Description: A propulsion and stabilization system with a plurality of superconducting magnetic devices affixed to the dual-keels of a vehicle, where the superconducting magnetic devices produce a magnetic field when energized. The system also includes a plurality of figure-eight shaped null-flux coils affixed to opposing vertical sides of slots in a guideway. The figure-eight shaped null-flux coils are vertically oriented, laterally cross-connected in parallel, longitudinally connected in series, and continue the length of the vertical slots providing levitation and guidance force. An external power source energizes the figure-eight shaped null-flux coils to create a magnetic traveling wave that interacts with the magnetic field produced by the superconducting magnets to impart motion to the vehicle.
Date: December 31, 1995
Creator: He, J.; Wang, Z.; Rote, D.M.; Coffey, H.T.; Hull, J.R.; Mulcahy, T.M. et al.
Partner: UNT Libraries Government Documents Department

The interaction of two narrow magnets and a moving conducting slip

Description: Measurements were made of the forces experienced by two narrow but relatively long permanent magnets positioned above a moving, electrically conducting surface. The intent was to determine the accuracy of various means of computing these forces. It was found that the behavior at very high speeds can be approximated by using elementary methods and making the assumption that magnetic images are formed in the conductor. At lower speeds, a published formulation that uses Fourier transform techniques is quite reliable for the parameters of the experiments. A commercial computer code that uses a finite-element method of analysis is also in good agreement The results are relevant to the design of high-speed magnetically levitated (maglev) ground transportation vehicles having multiple magnets, where the guideway consists of a continuous-sheet conductor.
Date: July 1, 1994
Creator: Wang, Z.; Winkleman, S. R.; Mulcahy, T. M.; Coffey, H. T.; Rote, D. M. & Hull, J. R.
Partner: UNT Libraries Government Documents Department