JPS6032410B2 - Magnetic shielding device for superconducting magnetic levitation vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic shielding device for a superconducting magnetically levitated wheel.

A conventional superconducting magnetic levitation wheel has a car body 1, a bogie 2, and a car body 1 constituting a passenger compartment, etc., as shown in FIG. A support and shock absorbing device 3 made of, for example, an air spring, for supporting on the trolley 2, a superconducting magnet 4 for levitation mounted on the trolley 2, and a superconducting magnet for propulsion guidance also mounted on the trolley 2. 5. Levitation coil laid on the ground (in addition to this, it may also be made into a conductive sheet such as an aluminum plate), Propulsion guide coil also laid on the ground 7
, and a magnetic shield plate 8 made of a magnetic material such as iron.
It is composed of etc.

The superconducting magnet 5 for propulsion guide and the coil 7 for propulsion guide constitute a linear synchronous motor. By applying a propulsion current to the propulsion guide coil 7, the superconducting magnetic levitation vehicle is propelled, and at the same time, a current is induced in the levitation coil 61 by the electromagnetic transfer action of the levitation superconducting magnet 4. The superconducting magnetic levitation wheel is levitated and supported by the electromagnetic repulsion force acting between the induced current and the levitation superconducting magnet 4. However, the levitation superconducting magnet 4 and the propulsion guide superconducting magnet 5
are very strong magnets to levitate and propel the car bran, and therefore the magnetic fields created by these superconducting magnets 4 and 5 are also strong, even in the passenger compartment, which is a certain distance from the superconducting magnets 4 and 5. , forming a fairly strong magnetic field. For example, the supermagnetic force of the superconducting magnet 5 for propulsion guide in a practical vehicle case is about 500 to 100 plates AT, that is,
Although it varies depending on the number, arrangement, and dimensions of superconducting magnets relative to the weight of the wheel, it is 500 to 600 KAT for a vehicle with separate superconducting magnets for levitation and propulsion guidance as shown in Figure 1. In addition, in the case where the levitation superconducting magnet 4 is omitted and the propulsion guide superconducting magnet 5 alone is used for levitation, it is 5.
The strength will be around 00 to 1000 KAT. Therefore, even on the floor surface 9 of the passenger compartment, which is approximately 800 to 120 meters away from the center of the superconducting magnet 5 for propulsion and guidance, the magnetic flux density is as follows: There are now 400 to 100 hawks. On the other hand, the effects of magnetic fields on the human body are currently under study, and the acceptable standards for magnetic field strength on the human body have not been clarified, but in general, it must be less than 20 eaves. It is said that Therefore, in the superconducting magnetically levitated car ball as described above, the magnetic field in the cabin is reduced to 2
It is necessary to provide magnetic shielding in order to reduce the auss to 0 auss or less, and for this purpose, a magnetic shielding plate 8 is provided. This is because magnetic materials such as iron have magnetic permeability peaks that are much larger than air's magnetic permeability peaks. Taking advantage of the property that magnetic flux passes through easier than in air, it is generated from superconducting magnets and transported into the cabin. A magnetic shield plate 8 is installed between the superconducting magnets 4, 5 and the floor 9 to collect and pass the magnetic flux that is about to enter, and prevent the magnetic flux from leaking into the cabin. However, when magnetically shielding is performed using a magnetic shielding plate 8 as shown in FIG. The disadvantage was that the effect of the method was not demonstrated.

The reason is that when the thickness of the magnetic shield plate 8 is thin,
Compared to when the magnetic shield plate 8 is thicker, magnetic saturation occurs due to a small concentration of magnetic wheels, the magnetic permeability decreases, and the amount of magnetic flux passing through the magnetic shield plate 8 is restricted, resulting in leakage into the cabin. This is because magnetic flux increases. Also,
In some cases, because the magnetic shield plate 8 collects magnetic flux, the magnetic flux density of the magnetic flux leaking into the passenger compartment may actually become higher than in the case where the magnetic shield plate 8 is not provided. Therefore, in order to expect a sufficient magnetic shielding effect, it is necessary to increase the thickness of the magnetic shield plate to the extent that magnetic saturation does not occur, but on the other hand, this also reduces the weight of the magnetic shield plate. This means a considerable increase.

This increase in weight is a serious drawback for wheels that levitate and support the weight of a car ball by electromagnetic force, such as the superconducting magnetic levitation wheel that is the object of the present invention. That is, the weight of the entire wheel increases due to the increase in the weight of the magnetic shield plate 8, and as a result, the electromagnetic force required to levitate and support the wheel also needs to be further increased. The magnetic force must also be increased, which is likely to lead to an increase in the weight of the superconducting magnet 4;
Since the magnetic field generated by this is also strengthened, it is necessary to further increase the thickness of the magnetic shield plate 8 in order to shield the passenger compartment, which further increases the weight of the magnetic shield plate. There is a high risk that this will lead to a repeat of the vicious cycle of weight gain. On the other hand, it is possible to avoid the above disadvantages by using a material with sufficiently large saturation magnetic permeability as a magnetic shielding material, but in this case, since it is a special material, it is difficult to use a magnetic shielding material. Another drawback is that the cost of the board increases significantly. In addition, a car ball is generally configured to provide a secondary suspension such as a coil spring or an air spring between the car body and the bogie to improve passenger comfort, but superconducting magnetic levitation Unlike a general wheel, the weight of the trolley 2 becomes extremely heavy compared to the weight of the car body due to the storage of superconducting magnets, etc., and the unsprung weight is greater than the so-called sprung weight. It's heavier.

If the unsprung weight is sufficiently large compared to the unsprung weight, the car body will not follow the vibrations of the bogie, and therefore a good ride will be obtained. If this is not the case, the car body 12 will vibrate following the vibrations of the truck 2, which may cause the straw D to deteriorate. The present invention aims to prevent the vehicle body from vibrating by following the vibrations of the bogie, without causing the vicious cycle of weight increase or soaring costs as described above, while enabling sufficient magnetic shielding. In order to achieve this purpose, a magnetic generator that electrically generates a magnetic field in a desired direction and a desired strength, a power source for generating the magnetic field, and a vibration generator that controls the vertical vibration of the vehicle body. By providing within the superconducting magnetic levitation vehicle a detection device for measurement and detection, and a control device for controlling and varying the current flowing in order to vary the strength of the magnetic field in response to the speed or acceleration of this vibration. This is characterized by eliminating or attenuating magnetic flux leaking into the passenger compartment generated from superconducting magnets for levitation and propulsion guidance, and also damping vibrations of the vehicle body.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings showing one embodiment thereof.

In FIG. 2, reference numeral 10 is a magnetism generating device consisting of a magnetic shielding coil wound with aluminum wire or copper wire, 13 is a DC variable power source constituted by, for example, a chopper, and 14 is an accelerometer or the like. A detection device 15 detects the acceleration or speed of the vehicle body 12 in the vertical direction; a DC variable variable current detector 15 is configured to apply a current corresponding to the vertical velocity or acceleration of the vehicle body 12 to the magnetic shielding coil 10 according to the output detection signal of the detection device 14; This is a control device for controlling the power source 13 and damping vibrations in the vertical direction of the vehicle body 12, and these are all attached to the vehicle body 12 to form a magnetic shield device.

The present invention not only shields magnetic flux leaking to the customer guide, but also detects the acceleration or speed in the vertical direction of the vehicle body 12, and uses this detection signal and the control device 15 to control the current flowing through the magnetic shield coil. The current required for this is used as a bias, and control is performed to correspond to the vertical acceleration or speed of the vehicle body 12.

As a result, the magnetic flux generated from the magnetic shielding coil 10 is controlled and changed to cancel out the electromagnetic force generated from the superconducting magnets 4 and 5, thereby shielding magnetic leakage into the passenger compartment, and applying damping to the vehicle body 12. Even if the weight on the springs, that is, the weight of the vehicle body 12 is much lighter than the weight of the bogie 2, a superconducting magnetically levitated vehicle cocoon with sufficiently good riding comfort can be obtained. Although the present invention has the above-described configuration, the suitability of the magnetic shielding coil 10 with respect to the polarity of the superconducting magnet will be explained based on FIG. 3 showing an example thereof.

In the figure, the superconducting magnets 4, 5 and the magnetic shielding coil 10' are shown as a single connection diagram, and the fourth
Figure A shows a case where the left and right propulsion guide superconducting magnets 5 have the same polarity, and Figure B shows a case where they have different polarities.

Further, the arrows in the figure simply indicate the directions of magnetic flux lines, and the solid line arrow P in the levitation superconducting magnet 4 indicates that the propulsion guide superconducting magnet 5 and the levitation superconducting magnet 4 are differentially excited. In addition, the broken line arrow Q indicates the case where they are summarily excited, and the arrow S indicates the superconducting magnet 4 for levitation and the superconducting magnet 5 for propulsion guide linked to the magnetic shielding coil. This shows the direction of the composite magnetic flux. - The superconducting magnet 4 for levitation is further away from the magnetic shielding coil 10 than the superconducting magnet 5 for propulsion guide, and the direction of the composite magnetic flux interlinking with the coil 1 for magnetic shield is the superconducting magnet 5 for propulsion guide. The direction is the same as the direction of the magnetic flux created by.

In this way, from the superconducting magnet toward the cabin, i.e.
Since a composite magnetic flux interlinking with the magnetic shielding coil 10 is generated, the magnetic shielding coil 10 is excited with a polarity that generates magnetic flux in a direction that cancels out this composite magnetic flux, and the magnetic shielding coil 10 is activated. A sufficient magnetic shielding effect can be obtained by setting the magnetic force so that the magnetic flux density in the cabin is below the allowable value.

The required supermagnetic force of the magnetic shielding coil 10 in this case is:
Although it varies depending on conditions such as the size of the supermagnetic force of both superconducting magnets 4 and 5, the size of the magnetic shielding coil 10, and their arrangement, for a practical range of vehicle height, it is several KAT ~
A magnetomotive force in the range of about 1 female AT is sufficient.

Therefore, for example, in the case of an aluminum magnetic shielding coil with a magnetomotive force of one plate AT and a width of about 80 mm,
Compared to the magnetic shield plate 8 which uses an iron plate with a thickness of 5 ribs,
It is possible to obtain the same or better magnetic shielding effect with about half the weight, and as a result, it is possible to obtain a lightweight magnetic shielding device that does not have drawbacks such as a vicious cycle of increased weight due to the installation of the magnetic shielding device or a rise in price. In addition, when the propulsion guide superconducting magnet 5 is excited with different polarities on the left and right sides, the center of the magnetic shielding coil 10 is connected to the vehicle body without providing the magnetic shielding coil 10 separately on the left and right sides as shown in FIG. There is no problem even if they are arranged in a line aligned with the center, and the effect is no different from the above effect. The structure, operation, and effects of the present invention are as described above, and second and third embodiments of the present invention will be shown below.

However, the detection device 14 and the control device 15 are omitted from the figures shown below. In other words, FIG.
The magnetic shielding coil 10 shown in the figure is installed so as to be spaced vertically from the floor surface 9 from the side end of the superconducting magnetic levitation wheel toward the center, and the reference numeral 20 indicates the magnetic This is a magnetic shielding coil that is a generator.

This is because the magnetic field created by both superconducting magnets 4 and 5 on the floor surface 9 has a distribution that decreases from the wheel side edge toward the center of the wheel, so the magnetic flux density on the floor surface near the wheel center is low. However, because the magnetic shielding coil 10 was installed parallel to the floor 9, the magnetic field generated by the coil side of the magnetic shielding coil 10 on the side of the center of the car cocoon was This is because there is a risk that the magnetic flux density in that part may exceed the permissible value as a result of overlapping.In order to avoid this fear, the coil side closer to the center of the wheel is moved away from the floor surface 9. The magnetic flux density on the floor surface 9 is suppressed to a low value. When tilted in this way, the degree of magnetic coupling between the propulsion guide superconducting magnet 5 and the magnetic shielding coil 20 increases, compared to the case where the magnetic shielding coil 10 is arranged in parallel.
It also has the advantage that an equivalent shielding effect can be obtained by using a smaller magnetomotive force. Next, what is shown in FIG. 5 is the magnetic shielding device shown in FIG. 2 in which a magnetic shielding plate 30 made of a magnetic material such as iron is added between the magnetic shielding coil 10 and the floor surface 9. Therefore, the high magnetic flux density in the part near the wheel side end, that is, the upper part of the propulsion guide superconducting magnet 5, is suppressed by the magnetic shielding coil, and furthermore, the three magnetic shielding plates are used to completely provide magnetic shielding. It is something.

Therefore, the magnetomotive force and coil width of the magnetic shielding coil 10 can be made smaller than when magnetically shielding is performed using only the magnetic shielding coil 10, and the amount of magnetic flux that must be magnetically shielded by the magnetic shielding plate 30 is reduced. Therefore, the magnetic shielding plate can be made as thin as one or two ribs, and the total weight of the magnetic shielding coil and the magnetic shielding plate can be made lighter than when magnetically shielding is performed using only the magnetic shielding plate. In addition, it is possible to reduce the power consumption and power supply capacity of the magnetic shielding coil. Next, what is shown in FIG. 6 is the magnetic shield plate 4.
A coil 41 is wound around 0 to cancel the magnetic flux generated from the superconducting magnets 4 and 5 and passing through the magnetic shield plate 40.
This is a type of electromagnet that has an iron core and a coil that generates a magnetomotive force by passing a current that generates magnetic flux in the magnetic shield plate 40.

Therefore, the magnetic flux generated from the superconducting magnets 4 and 5 collected by the magnetic shield plate 401 can be effectively canceled out or reduced, and as a result, the thickness of the magnetic shield plate 40 can be reduced to about 1 to 2 legs. Not only can it be made thinner, but also the supermagnetic force of the magnetic shielding coil 41 can be sufficiently reduced, and the weight of the magnetic shielding device can be reduced and the power consumption and power supply capacity can be sufficiently reduced. In addition, the 6th
In the figure, the magnetic shield plate 40 is shown as a single plate, but even if the magnetic shield plate is divided into left and right parts, or if the propulsion guide superconducting magnets have different polarities on the left and right sides, the magnetic shield plate 40 There is no problem even if the coils to be wound are gathered together into one, or even if they are distributed in the width direction.
The effect is almost the same. As described above, according to the present invention, the magnetic flux leaking into the cabin from both superconducting magnets is eliminated or attenuated by providing a device that electrically generates a magnetic field in a desired direction and with a desired strength. The present invention has the effect of providing a magnetic shielding device that is capable of sufficiently satisfactory magnetic shielding indoors and is inexpensive and lightweight. In addition to the effect of magnetic shielding, the damping function of the vertical vibration of the vehicle body is significant, and as a result, it has the effect of significantly improving passenger safety. In each of the above embodiments, the trajectory of the superconducting magnetic levitation car ball is U-shaped, and the superconducting magnets are arranged in an L-shape for levitation and propulsion guidance, but the present invention is not limited to this. , even when the track is in an inverted T-shape (↓-shape), or when the superconducting magnets are arranged in a 1-shape arrangement that omits the superconducting magnet for levitation, the effect is no different from the above-mentioned effect; Even in the case of a configuration without a secondary suspension, the magnetic shield'
This related effect is no different from the above effect.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a superconducting magnetically levitated vehicle cocoon and its track at a cross section perpendicular to the direction of travel of the vehicle, and FIG. 2 is a schematic cross-sectional view similar to FIG. 1 of an embodiment of the present invention. ,
FIG. 3 is a single line diagram showing the polarity of the magnetic shielding coil with respect to the polarity of the superconducting magnet, and FIGS. 4, 5, and 6 are schematic sectional views similar to FIG. 1 showing other embodiments. 1, 12...car body, 2...bogie, 3...
... Support and shock absorber, 4 ... Superconducting magnet for levitation, 5 ... Superconducting magnet for propulsion guide, 6 ...
...Floating coil installed on the ground, 7... Propulsion guide coil installed on the ground, 8, 30, 40... Magnetic shield plate, 9... Floor surface, 10, 20,41...
...・Magnetic generator (magnetic shielding coil), 13...
. . . DC variable power supply, 14 detection device, 15 . . . control device. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. In a superconducting magnetic levitation vehicle, a magnetic generator comprising a normal conducting coil that electrically generates a magnetic field in a desired direction and a desired strength to reduce the magnetic field generated by the superconducting magnet and penetrating into the cabin; A power source for causing the generator to generate a magnetic field, a detection device for detecting vibration acceleration or vibration speed in the vertical direction of the vehicle body, and a current that energizes the magnetic generation device in response to a detection signal output from the detection device. What is claimed is: 1. A magnetic shielding device for a superconducting magnetically levitated vehicle, comprising: a control device for controlling a superconducting magnetic levitation vehicle.