JPH03128602A - Ground coil for propulsion of superconducting magnetic levitated ground transportation system - Google Patents

Abstract

PURPOSE:To reduce the conductor sectional areas of leads and cables by collecting ground coils for propulsion at every plural and housing each of the coils in conductive sealed vessels, into which an insulating gas is sealed. CONSTITUTION:Ground coils 1 for propulsion arranged and mounted in the travelling direction of a vehicle are collected at every plural, and each of the ground coils 1 is housed in sealed vessels 4, into which an insulating gas is sealed. Since the insulating gas has insulating performance higher than air by several times, the degree of insulation to the ground of the coil 1 can be improved easily. Consequently, the burden voltage of one coil 1 is elevated, and currents per one turn are reduced. Accordingly, the conductor sectional areas of leads 21 connecting sections among the coils 1 in series and cables 23, etc., connecting sections among the sealed vessels 4 can be diminished. The sealed vessels 4 are given conductivity, thus electrostatically interrupting the coils 1 from the outside, then reducing the effect of overcurrents.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention provides a superconducting magnet as a field pole in a vehicle,
A propulsion ground coil for superconducting magnetic levitation railways that provides propulsion force to the vehicle as a linear synchronous motor by arranging propulsion ground coils as armature coils on the track in the running direction of the vehicle and passing multiphase alternating current through these propulsion ground coils. Regarding.

[Conventional technology]

This type of propulsion ground coil consists of rectangular coils with a length of about 2 m arranged on the track in the direction of vehicle travel, and about 300 coils connected to a common three-phase AC power supply. It is a system that continuously supplies propulsive force to a vehicle traveling at high speed by sequentially passing current through the power supply sections as the vehicle travels, and the length of one power supply section is approximately 500 m. The power consumed by one vehicle is a large amount of power that exceeds the subordinate KVA. Most of this power is due to windage losses during high-speed driving, and is particularly large in tunnels. Propulsion ground coils play the role of providing such large amounts of power to vehicles from the ground side, but from the standpoint of efficiency and control characteristics, there are restrictions on the inductance and resistance values of the individual coils that make up the propulsion ground coils. In particular, the resistance value is required to be as small as possible in order to not only affect efficiency at high speeds but also to obtain a guiding force to suppress lateral fluctuations of the vehicle caused by the propulsion ground coil at low speeds.

FIG. 6 is a plan view of one coil constituting a conventional propulsion ground coil, and FIG. 7 is a sectional view taken along line C-C in FIG. 10A e, and is configured to be fixed to a track (not shown) by bolts 13, and FIG. 7 shows a structure including a coil conductor 11 around which a coil 10 is wound in a plurality of turns, and a mold resin 12 for molding the coil conductor 11. has been done. As described above, such a coil 10 is connected in about 100 fine lines for each phase, and then connected in three phases to the aforementioned three-phase AC i source.

Approximately 100 coils that make up one phase are connected in series to prevent current imbalance between the coils, but since many coils are connected in series, the voltage of one coil is small. The overall voltage is also high. As shown in Figure 6, the coil IO is insulated with molded resin, but it is surrounded by air and is used exposed to wind, rain, and sunlight, so it is not possible to apply a very large voltage to it. The limit for such a configuration is 20KV.

Therefore, the number of coils constituting one phase is 100, which is a low value that does not cause any problems. However, a voltage of 20 V is applied between the coil near the voltage application end and the ground.

[Problem to be solved by the invention]

As mentioned above, in the configuration in which the individual coils IO that make up the propulsion ground coil are resin-molded, the voltage of one phase is 2.
0KV is the limit. On the other hand, the ampere turns of one coil must be as large as about 10 KAT.

As mentioned above, the voltage per coil is limited to about 200V, so the number of turns is limited, and the current per turn has to be large in order to secure the above-mentioned ampere turns. Since it is necessary to keep the resistance value of the coil low, the cross-sectional area of the coil conductor per turn becomes even larger. Therefore, the leads that connect the coils in series become thick, and it takes a lot of time to connect the coils when installing the propulsion ground coil. In addition, the power supply line that connects the substation where the three-phase power supply is installed and the power supply section in the running direction has a large current and, as mentioned above, a high voltage of 20KV, so there is a space to route this power supply line for insulation. becomes larger. Particularly in the case of a power supply line to a power supply section in a long tunnel, the large space to route it is a great disadvantage.

In order to alleviate the various problems caused by the large current of the propulsion ground coil, it would be possible to increase the voltage, but as mentioned above, the voltage is limited to 20KV, so To mold a coil to withstand this voltage, insert the coil to be molded into a mold in the same way as applied to molded products of high voltage equipment,
It was necessary to inject the resin mold and heat it for curing over 10 hours, and the equipment and production costs for this were enormous.
The problem is that it is not necessarily appropriate from an economic standpoint.

This invention solves the above-mentioned problem and connects the individual coils by increasing the ground voltage strength of each coil constituting the propulsion ground coil and reducing the current per turn. It is an object of the present invention to provide a ground coil for propulsion of a magnetically levitated railway, which is economically advantageous and has a small cross-sectional area of a feeder connecting a lead, an I&

[! ! Means for Solving Problem 1] In order to solve the above problem, according to the present invention, ground coils for propulsion are installed on a track on which a vehicle equipped with superconducting magnets runs in parallel in the running direction of the vehicle. A plurality of individual coils are grouped together and each is housed in a sealed container filled with insulating gas, and these sealed containers have high resistance conductivity. The coil is considered to be one power supply cefsilane, and the propulsion ground coils included in this power supply cefsilane are housed in a plurality of sealed containers, and these plurality of sealed containers are communicated with each other through an insulating gas passage. A cable that electrically connects the propulsion ground coil in the container shall be passed through the insulating gas passage, and the connection between the insulating gas passage and the sealed container shall be provided with an airtight terminal to which the cable is connected, and A valve that can be opened and closed from the outside shall be provided to communicate the insulating gas passage and the sealed container.

[Effect]

In the configuration of this invention, if a plurality of propulsion ground coils arranged in the running direction of the vehicle are collectively stored in a sealed container filled with insulating gas, the insulating gas has a higher insulation performance than air. Since it is several times higher, the ground insulation strength of the coil can be easily increased. therefore,
Since the burden voltage of one coil can be increased, the current per turn can be reduced. As a result, the cross-sectional area of conductors such as leads connecting coils in series, cables connecting sealed containers, and feeder lines connecting three-phase power sources can be reduced. By making the sealed container electrically conductive, the propulsion ground coil is electrostatically isolated from the outside, and by making the electrical conductivity an order of magnitude higher in resistance than metal, the effects of eddy currents can be virtually eliminated. can be eliminated. In addition, by storing the propulsion ground coil included in one power supply cefsilane in multiple sealed containers and communicating these multiple sealed containers with an insulating gas passage, these sealed containers can start and stop power supply at the same time. This makes it easier to manage the installation of the sealed container during removal work, inspection, etc. Furthermore, by passing the cable that electrically connects the propulsion ground coils in adjacent sealed containers through the insulating gas passage, we can create an insulation system that gas-insulates the cable that connects the sealed containers without providing a dedicated cable container. configuration can be adopted. In addition, by closing the connection between the cable container and the sealed container with an airtight terminal for the cable and providing a valve that can be opened and closed from the outside instead, this valve can be left open while the propulsion ground coil is in use. Since the air pressure in all sealed containers and cable containers for each power supply cefsilane is the same, by providing one barometer for one power supply cefsilane, the gas pressure of the insulating gas can be monitored, and abnormalities can be detected. If a failure occurs, the power supply can be stopped all at once, making maintenance and inspection easier. In addition, since a single sealed container in which a failure has occurred can be shut off using a valve, removal and installation are quick and easy. Can be done.

〔Example〕

The nine inventions will be explained below based on examples. FIG. 1 is an elevational view including a partial internal structure and a sectional view showing an embodiment of the present invention, 4A and 48.4G are sealed containers, and a portion of the sealed container is shown to show the internal structure. The illustration is shown with the front wall removed. Note that when not specifically specifying a single sealed container or when describing matters common to all sealed containers, the reference number for the sealed container is 4.

The left-right dimension of the sealed container 4 in FIG. 1 is about 10 m, and four coils 1 are housed therein. If the number of coils 1 is 300 in one power supply cefsilane, the failure of the sealed container 4 is 75. Although these numbers are generally close to the actual values, they are provisional, and we are not particularly particular about these numbers.

When there are coils 1 of the same phase in one sealed container 4, connect them with the leads 21 inside the sealed container 4. To connect the coils 1 of the sealed container 4B and the adjacent sealed container 4C, use the leads 21. Cable container 3B connected to cable 23 via airtight terminal 22 to connect sealed containers 4B and 4C.
Similarly, it is pulled out from the adjacent sealed container 4B and connected to the cable 23.

The total number of coils 1 in one phase is about 100 as mentioned above, and the number of coils 1 that can be stored in one sealed container 4 is only a few due to dimensional limitations in manufacturing the sealed container. Connections between containers 4 are essential.

The sealed container 4 is filled with an insulating gas made of sulfur hexafluoride, which is usually called SFa. This insulating gas is used in gas insulated switchgear called GIS, etc.
Widely used in high-voltage equipment, it has an insulating strength several times that of air at normal pressure, and exhibits high insulating properties comparable to insulating oil when the pressure is increased.

FIG. 2 is a sectional view taken along the line AA in FIG. 1. In this figure, the sealed container 4 is integrally formed by covering a bottom plate 41 with a U-shaped cover 42 and attaching it to the surrounding flange with bolts 7, and is attached to the vertical surface of the track 9. The interior is kept airtight by a gasket 71. The coil 1 is fixed to the bottom plate 41 via an insulating spacer 43, and the insulating spacer 43 ensures the insulation strength of the coil 1 to the ground. The coil 1 is sandwiched between an insulating spacer 43 and a coil holder 44 and fixed by tightening with an insulating bolt (not shown).

If the sealed container 4 is made of metal such as a mesh plate, eddy currents will flow due to the magnetic flux generated by the superconducting magnets and coils 1 mounted on the vehicle, and not only will eddy current losses occur, but the relationship between the superconducting magnets and the coils 1 will The sealed container 4 cannot be made of metal because the magnetic coupling between the two and the propulsion ground coils will be inhibited and the propulsive force and guiding force applied to the propulsion ground coil will not be generated as expected. It is appropriate that the sealed container 4 is made of glass fiber reinforced synthetic resin commonly called FRP. However, since normal FRP is an insulating material, when the coil 1 becomes high voltage, the electric field leaks outside the sealed container 4 and a partial discharge occurs outside the sealed container 4. It is necessary to have enough conductivity to act as an electrostatic shield to prevent leakage to the outside. One method is to mix carbon powder or metal powder to make it conductive, or use a synthetic resin that itself has NL'gl properties, and the other method is to use carbon fiber instead of glass fiber. Another method is to increase mechanical strength and provide conductivity using
There are various methods such as applying conductive paint to the inner surface of the sealed container 4, and any method may be adopted as long as it closely relates to the purpose of this invention. Since the resistance value is generally an order of magnitude higher than that of metal, the influence of eddy currents can be ignored.

FIG. 1 shows a cross section of a cable container 3 that connects the sealed containers 4, and the inside of the cable container 3 is also filled with insulating gas like the sealed container 4. Therefore, the insulation of the airtight terminal 22 and the cable 23 can utilize the excellent insulation properties of the insulating gas, so that a simple structure and small size are sufficient.

FIG. 3 is a cross-sectional view taken along the line BB in FIG. 1, showing an enlarged view of the portion where the airtight terminal 22 is provided between the sealed container 4 and the cable container 3. In this figure, airtight terminal 2
2 is an insulating plate 24 and a through conductor 2 passing through this insulating plate 24
5, and the insulating plate 24 isolates the spaces between the sealed container 4 and the cable container 3.

FIG. 4 is a sectional view of a main part showing details of the valve 5 shown in FIG. 1 and its surroundings. In this figure, the valve 5 normally closes the hole 54 by the force of the spring 55 as shown in the figure, and the gasket 56 closes the hole 54.
The space in the upper sealed container 4 and the cable container 3 in the figure are
The structure is such that it is possible to airtightly isolate the space between the To connect these, raise the opening/closing screw 57 from the position shown in the figure to the top of the figure, push the valve 5 upward, and push the valve 5 upwards.
By opening the container, the sealed container 4 and the cable container 3 can be connected to each other. Two such valves 5 are attached to each cable container 3 so that adjacent sealed containers 4 can communicate with each other via the cable container 3.

Therefore, the internal spaces of all of the sealed containers 4 connected to one three-phase power supply and all of the cable containers 3 that connect them are communicated with each other. While the propulsion ground coil is in use, all the sealed containers 4 and cable containers 3 connected to one Sanwa power source are kept in a state where insulating gas is passed through them so that the internal pressure of each container is the same. By monitoring this internal pressure with a pressure gauge (not shown), the insulation of the sealed container 4 in which the propulsion ground coil is operated can be managed for each power supply section.

FIG. 5 is a conceptual diagram showing a state in which an insulating gas cylinder is attached to one power supply cefsilane.
Although only five are shown in the diagram, in reality, as mentioned above, one power supply section is constituted by a row of long sealed containers 4 with a total length of several hundred meters by lining up dozens of sealed containers 4. .

The insulating gas cylinder 83 is connected to the insulating gas supply ports 81 of the sealed containers 4Y and 4Z at both ends of the power supply Cefsilane, and a pressure gauge 84 is connected to the insulating gas cylinder 83.
In addition to monitoring the internal pressure throughout this feeding section,
A system is provided for replenishing the sealed container 4 with insulating gas as necessary. Since the insides of these sealed containers are connected, all the sealed containers 4. It is also possible to monitor the internal pressure of the cable container 3, and of course it is also possible to monitor only one of them using the pressure gauge 84.

〔Effect of the invention〕

As described above, this invention allows the ground insulation strength of the coils to be easily increased by storing multiple propulsion ground coils in a sealed container filled with an insulating gas whose insulation performance is several times better than that of air. be able to. Therefore, since it is possible to increase the burden voltage of one coil, l
Current per turn can be reduced. As a result, the cross-sectional area of conductors such as the leads that connect coils, the cable that connects sealed containers, and the feeder line from 14B can be reduced. In addition to making it easier to route the power lines, this also has the effect of reducing the space required to route the power lines inside the tunnel. By making the sealed container conductive, it electrostatically isolates the propulsion ground coil from the outside, and by making its resistance an order of magnitude higher than that of metal, it is possible to prevent electrostatic shielding. The influence of eddy currents can be substantially eliminated while maintaining sufficient effectiveness.

In addition, by connecting multiple sealed containers included in the power feeding cefushiran as one unit through insulating gas passages, the propulsion ground coils housed in these sealed containers can start and stop power supply at the same time. This facilitates work such as inspecting the inside of a sealed container, resulting in lower manufacturing costs and improved maintainability.

Furthermore, by using the insulating gas passage as a cable container and passing the cable that connects the propulsion ground coil in the adjacent sealed container through this cable container, an insulation structure is created in which the insulation of the cable with respect to the container is insulated by the insulating gas. Since it can be used, cables with high insulation reliability can be used! This has the effect of contributing to improving the reliability of the entire propulsion ground coil.

In addition, if the connection between the cable container and the sealed container is closed with an airtight terminal for the cable, and a valve that can be opened and closed from the outside is installed instead, and this valve is left open while the propulsion ground coil is in use, the power supply cefsilane Since the internal pressure of all sealed containers and cable containers is the same for each section, it is possible to monitor the gas pressure of the insulating gas by providing one barometer in one power supply section, and if an abnormality is detected, Since the power supply can be stopped all at once, maintenance and inspection becomes easy, and since a single sealed container in which a failure has occurred can be shut off using a valve, removal and installation can be done quickly and easily. This provides the advantage of providing a ground propulsion coil with excellent maintainability.

Furthermore, since the propulsion ground coil is housed in a sealed container,
Since the propulsion ground coil is no longer directly exposed to wind, rain, or sunlight, the weather resistance of the propulsion ground coil is greatly improved, and its third-class characteristics are improved.

Even if the surface of the sealed container deteriorates, the effect is slight because it has no direct effect on insulation performance.

In the case of the present invention, it is appropriate that the individual coils constituting the propulsion ground carp E are resin-molded in order to bond the wound conductors together and integrate them as a whole. Since the voltage burden on the coil is small, there is no need to form a thick coating with mold resin, and even if air bubbles remain between the conductors, there is no problem with insulation.Generally, high voltage molding equipment is molded with resin. In this case, the molding resin is injected in a vacuum, which requires large-scale equipment, but as mentioned above, this invention does not require this, so equipment for molding the individual coils of the propulsion ground coil is required. It can be something simple.

[Brief explanation of the drawing]

FIG. 1 is an elevational view including a partial cross-section of a propulsion ground coil and its sealed container showing an embodiment of the present invention, and FIG.
! Fig. 3 is a sectional view taken along line BB of Fig. 1;
Fig. 4 is a sectional view of the main part of Fig. 1, Fig. 5 is a conceptual diagram showing a sealed container of one power supply, Fig. 6 is a plan view of one coil constituting a conventional propulsion ground coil, and Fig. 7 The figure is number 6
It is a sectional view taken along line C-○ in the figure. X, tO: Coil, 10A: Mounting part, 21: Lead,
22: Airtight terminal, 23: Cable, 24: Insulating plate, 25
: Penetrating conductor, 3.3A, 3B : Cable container (insulating gas passage), 4.4A, 4B, 4G, 4Y, 4z: Sealed container, 43: Insulating spacer, 5: Valve, 54: Hole, 55
Spring, 7156: Packing, 57: Opening/closing screw, 7.13: Mounting bolt, 81: Insulating gas supply port,
83: Insulating gas cylinder Figure 4

Claims (1)

[Scope of Claims] 1) A plurality of individual coils constituting a propulsion ground coil are arranged in parallel in the running direction of the vehicle on a track on which a vehicle equipped with a superconducting magnet runs, and each coil is insulated with an insulating gas. 1. A ground coil for propulsion of a superconducting magnetic levitation railway, characterized in that the sealed container has high resistance conductivity. 2) Multiple coils supplied with power from one power supply are considered as one power supply section, and the propulsion ground coils included in this power supply section are housed in multiple sealed containers, and these multiple sealed containers are communicated through an insulating gas passage. The ground coil for propulsion of a superconducting magnetic levitation railway according to claim 1. 3) The propulsion ground coil for a superconducting magnetic levitation railway according to claim 2, wherein a cable for electrically connecting propulsion ground coils in adjacent sealed containers is passed through an insulating gas passage. 4) A claim characterized in that the connecting portion between the insulating gas passage and the sealed container is provided with an airtight terminal to which a cable is connected, and a valve that can be opened and closed from the outside and communicates between the insulating gas passage and the sealed container is provided. 3. The ground coil for propulsion of a superconducting magnetic levitation railway as described in 3.