JPH077812A - Electromagnetic suspension system using superconducting magnet - Google Patents

Abstract

PURPOSE: To levitate and drive a vehicle with safety by constituting a magnetic levitation system of an induction circuit of a magnetic material in the lengthwise direction and a vehicle suspension member with a superconducting coil wound on a core formed of a magnetic material and passing currents through the superconducting coil. CONSTITUTION: Rails 7 formed of a magnetic material are extended along an induction circuit 3 in the lengthwise direction. Vehicle suspension members 4 partly facing the rails 7 and separated from each other by a gap are installed. The vehicle suspension members 4, together with a core 5 obtained by laminating iron cores formed of a magnetic material and a superconducting coil 8 wound on the core 5, forms a levitation system. When a current is passed through the superconducting coil 8, magnetic fields are excited in the core 5, and the core 5 is attracted to the rails 7. As a result, the width of the gap is reduced, and the vehicle suspension members 4 are levitated. The vehicle suspension members 4 have cross sections almost in U shape, comprise suspended sections on both sides and a suspension supporting body 6 located at the upper part, and secure passenger cars 2. As a result, the vehicle are levitated and driven with safety, and the magnetism in the passenger cars is weakened, costs for construction and security being reduced.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to high speed transportation system electromagnetic suspensions.

[0002]

2. Description of the Prior Art Conventional drive means for railway transportation systems comprising drive motors and wheels are practically impossible to use at speeds above 300 km / h. Problems with conventional systems include running resistance, rail-to-wheel stickiness, wind obstruction, inertia effects, roadbed bumps, and propulsion difficulties. To overcome these problems, instead of wheels and mechanical suspensions, electromagnetic suspensions and stabilization systems are used to reduce dynamic friction, thus enabling ultra-high speed operation while simultaneously reducing energy consumption. Various systems have been proposed. The amount of energy used in such a system is further reduced by using the technique of superconductors in which power is passed through a wire with little internal electrical resistance, thus adding to the energy efficiency of the system, It can improve performance, price, safety and environmental impact.

The technology of magnetic levitation (MAGLEV) can be broadly classified into two main types of suspension systems: attractive or electromagnetic suspension (EMS) systems, and repulsive or electrodynamic suspension (EDS) systems. Is.

The EMS system, which took about 20 years to develop and is about to be put to practical use, is a German high speed transportation system (German T).
ransrapid System). This system uses a conventional (non-superconducting) electromagnet to lift the vehicle into the air by the attraction of a ferromagnetic rail mounted on the taxiway.

The current development of high speed transportation systems has several important advantages and disadvantages. Positive aspects are its low energy consumption, resistance to derailment, and low magnetic field strength in the cabin. The disadvantage of this system is the small 1 cm (0.4 inch) clearance required between the poles and the guideway, which increases manufacturing and maintenance costs.
And heavy vehicle weight due to the use of normal magnet systems,
Includes limited payload or freight capacity.

On the other hand, in Japan, an EDS system (MLU series) having a speed close to 300 mph is constructed and tested. The system, unlike the German Fast Transit System, utilizes the technology of superconducting magnets and therefore operates with wide gaps (4-6 inches). However, JR (Japanese
The air-core superconducting system used by Railway suffers from the magnetic quanch due to the dynamic effect, suffers from the drawback of very high magnetic field level in the vehicle, and for load bearing coils. Requires significant additional component support. The need for a support to carry the load on the coil creates a problem of heat loss from the coil to the warm component support. Furthermore, EDS systems require relatively complex taxiways,
It can levitate only when a certain speed is achieved, requiring auxiliary wheels. An example of an air-core superconducting system for application to MAGLEV is given in US Pat. No. 3,913,492.
Disclosed in the specification.

It can therefore be seen that neither of the two existing MAGLEVs is completely satisfactory. Conventional E
By abandoning the use of ferromagnetic rails to contain the magnetic flux as in MS magnet suspension systems, air-core superconductor coils like those used in Japanese systems
It presents a significant problem due to the large and unconfined magnetic field generated by the coil and due to the loading required to support the coil. Meanwhile, German EM
The S system does not present such a problem and the use of conventional electromagnets limits the possible attractive force for a given current, thus reducing the size of the gap as described above.

[0008]

In view of the shortcomings of the German EMS system and the Japanese superconducting EDS system described above, the German EMS system and the Japanese system without incorporating the drawbacks of the two systems. It is the first object of the present invention to incorporate the best features of both of the EDS systems.

It is a second object of the present invention to provide an EMS system that utilizes superconductor technology while minimizing external magnetic field levels.

The magnitude of the spacing between the vehicle and the taxiway is maximized by using a superconducting coil, while at the same time placing an iron core in the coil to minimize the load on the coil while maintaining the ampere turn of the electromagnet. MA to increase the value of
It is a third object of the present invention to provide a GLEV suspension system.

It is a fourth aspect of the present invention to provide a MAGLEV transport system that uses a superconducting technique in which the coil is effectively insulated from the inductive path, thereby facilitating cooling of the superconducting coil and minimizing heat loss. Is the purpose of.

It is a fifth object of the invention to provide a MAGLEV system with all of the following advantages: Ability to operate safely at all speeds; 1. 2. Stray magnetic fields in the cabin limited to a few Gauss DC and a few Gauss AC; Minimum taxiway cost; 4. 4. Controllable on-board power requirement; 5. A vehicle that does not derail almost at all; An air gap between the vehicle and taxiway that is adequate to provide clearance under normal operating conditions and to minimize taxiway installation and maintenance costs

[0013]

These objects are achieved by providing a coil of a superconductor having an iron core and confining the magnetic flux in a rail provided on the iron core and on the guideway. While supporting the weight of the vehicle, it acts to confine the magnetic flux and minimize stray magnetic fields. The use of a superconducting magnet with an iron core allows the weight of the vehicle to be supported by the iron core rather than by the coil, thus eliminating the heat leakage problem associated with transferring a large load from the superconducting coil to a relatively warm support configuration. It can be reduced.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cross-sectional view illustrates a MAGLEV vehicle and rail system 1 which is similar in overall construction to the German rapid transit system. A railway passenger car 2, a taxiway 3, a vehicle suspension system 4 and a suspension support 6 are included.

Although the suspension system 4 is illustrated as being used with a single taxiway 3, it is also possible to have two taxiways attached to the preferred system. The shape and content of the vehicle is, of course, a matter of design choice in the context of the present invention, and in any case, the present invention is not limited to individual vehicle or freight vehicle types, or over long distances. It is not limited to any particular application, such as the illustrated rapid mass transit system for transporting a.

The main loads on the suspension are due to the weight of the vehicle and the reaction forces generated by the propulsion system. This weight is supported by the laminated iron rail 7 mounted on the extension 10 of the guideway 3. As is known, suspension configurations of various electromagnets or permanent magnets such as the magnet 12 shown can be used to achieve lateral stability of the vehicle 2. A conventional auxiliary electromagnet system may be provided if an even faster suspension response is required.
Each of these elements may be conventional and none form part of the invention.

As best shown in FIGS. 2 and 3, the suspension system 4 comprises a substantially W-shaped laminated core arrangement 5 mounted on a suspension support 6 to form the core of a superconducting magnet,
The attraction of the laminated iron core rail 7 mounted on the portion 10 extending downward from the taxiway 3 lifts the vehicle into the air. The superconducting coil 8 is mounted on the central leg 9 of the W-shaped core arrangement 5. The coil can be activated in either a permanent mode, where the magnet appears to last without power, or in a powered mode where the magnetic flux is changed.

The superconducting coil 8 surrounding the central leg 9 of the member 5 is housed in a cryocontainer 11 which is sealed for cooling. Preferably the container is filled with liquid helium and is annular in shape to surround the legs 9. Vessel 11 may be configured to have a vacuum region 14 surrounded by a helium filled chamber 15. The vacuum region is about 3 centimeters of super insulator (supe), as is known in the art of superconducting magnets.
rinsulation) or metallized Mylar
^TM ) (not shown) may also be included. However, it will be appreciated that in light of future developments in high temperature superconductor technology, the cooling structure may be modified or omitted.

It will also be appreciated by those skilled in the art that additional propulsion systems are needed to move the vehicle along the taxiway. Although the propulsion system does not form any part of the present invention, various highly efficient superconducting linear induction motors that can be used in conjunction with the preferred suspension system are proposed. FIG. 3 shows a slot 16 in the laminated rail 7 for positioning a propulsion coil (not shown).

Instead, as shown in FIG. 4, the core 5 is U
It is provided with two legs of a U-shape, the base part and its end facing the rail 7, together with a coil 8 surrounding the U-shaped base part. Of course, it will be appreciated that the coil 8 is shown schematically and in practice it will be housed in an annular cryocontainer similar to that shown in FIGS. For many applications, the shape of FIG. 4 is preferred over that of FIGS.

An exemplary geometry of the suspension system of the invention uses a clearance of about 2 inches and a flux density of 1.5T. 10
About 1 of a superconductor to support a load of 10,000 pounds
A 20 kiloampere turn is required. This 120 kiloampere turn requirement is significantly lower than the 700 kiloampere turn required for the Japanese EDS system. The total weight of a typical aerial levitation system is about 3,48
It will be 5 pounds. However, weight reduction may not be the best situation, because in many systems increasing the cost per vehicle and using more iron cored superconducting magnets in the vehicle results in smaller rail sizes. , Because it leads to the cost saving of the system as a whole.

The use of iron in a substantially enclosed magnetic circuit means that the stray external flux density is minimal. The external magnetic field near the gap is determined by the size of the gap and the external magnetic field, which is the magnetic field in the iron. The BH curve determines the strength of the magnetic field on the iron surface. Normally, the 1.8 T magnetic field in iron is 0.
Producing a surface magnetic field of 005T to 0.01T (50 to 100 Gauss), which will be further reduced in size by several orders of magnitude with proper shielding in the passenger car, will provide a safe magnetic environment.

A problem that occurs with iron core magnets operating at 1.8T is that it needs to be subject to large current fluctuations in the superconducting magnet for control because it passes near the saturation limit of iron. . If this is needed, an additional smaller core magnet, operating at room temperature or superconductivity at 1T, can be included to moderate the coil current to control the air gap height. The problem can be overcome by providing sufficient coverage.

One of the main features of this shape is that most vehicle weight is transferred to the iron rather than the conductor. This is a major structural advantage of superconducting magnet systems.
In an air-core system, the force is applied directly to the superconducting coil. These loads must be transferred from the cold coil through the heavy struts to room temperature components, with the associated large amount of heat leakage. The main magnetic force is the iron that surrounds the conductor and is supported by this iron. The force on the conductor is reduced to a small part of it during the air-core system. This low force environment reduces the risk of magnet clench due to winding slippage due to heavy loads and is very beneficial in the design of superconducting windings.

The underlying concept of the preferred embodiment of the present invention is:
Many methods may be provided without departing from the scope and spirit of the invention. Therefore, the above description should not be read as limiting. Instead, the invention will be limited only by the claims.

[Brief description of drawings]

FIG. 1 is a cross-sectional end view of a MAGLEV vehicle and taxiway including a suspension system constructed in accordance with the principles of the preferred embodiment of the present invention.

2 is a partially enlarged cross-sectional end view of the main components of the suspension system shown in FIG.

3 is a perspective view of the main components of the suspension system shown in FIG.

FIG. 4 is a perspective view of a preferred alternative variation of the main suspension component shown in FIGS. 1-3.

[Explanation of symbols]

1 ... Rail system, 2 ... Passenger car, 3 ... Taxiway, 4 ... Vehicle suspension system, 5 ... Laminated core structure, 6 ... Suspension support,
7 ... laminated core rail, 8 ... superconducting coil, 9 ... central leg, 10 ... extension, 11 ... container, 12 ... magnet, 14 ... vacuum region,
15 ... Helium filling chamber, 16 ... Slot.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 593084937 Intermagnetics General Corporation INTERMAGNETICS GENE RAL CORPORATION USA, NY 12084, Guilderland, New Kerner Rod, Charles Industrial Park, P.P. Oh Box 566 (72) Inventor Richard J. Haberman, New York, USA 11743, Huntington, High Point Drive 16 (72) Inventor Dennis Earl Hull United States, New York, 12019, Ballston Lake, Phillips・ Street 1 (72) Inventor Zet J. J Steley 30 Hampshire Road, Wayland, MA 10778, Massachusetts, USA

Claims (10)

[Claims] 1. A guideway having a magnetically permeable rail (7) extending along the longitudinal axis of the guideway and partly facing said rail and separated therefrom by a gap. A magnetic levitation system comprising a vehicle suspension member (4) having a magnetically permeable core (5), the coil causing a magnetic field in the core when a current is present in the superconducting coil (8). A magnetic levitation system characterized by the superconducting coil surrounding the core such that it induces the core to be attracted to the rails to reduce the width of the gap. 2. System according to claim 1, characterized in that the core (5) is composed of laminated iron. 3. The core (5) comprises a central leg (9),
Having a substantially W-shape with the superconducting coil (8) surrounding the central leg and the distal end of each leg having a surface facing the rail across the gap. The system according to any one of claims 1 and 2. 4. The core (5) has a generally U-shape with one base and two legs, the distal ends of the legs facing the rail across the gap. System according to claim 1 or 2, characterized in that it comprises a surface and the superconducting coil (8) surrounds the base part. 5. System according to claim 1, characterized in that the superconducting coil (8) is enclosed in an annular cryocontainer. 6. The magnetic levitation system according to claim 1, wherein the rail (7) is a laminated iron rail. 7. A system according to claim 1, wherein the coil (8) is a 120 kampere turn superconducting coil. 8. System according to any one of the preceding claims, characterized in that the vehicle suspension member is mounted on a railway passenger car (2). 9. The width of the gap from the core (5) to the rail (7) when the current is present in the coil (8) is about 2 inches. 8. The system according to any one of 8. 10. A MAGLEV railway system characterized by a vehicle (2) and the magnetic suspension system of claim 1 wherein said vehicle suspension member (4) is mounted on said vehicle.