JP3370634B2 - Magnetically shielded DC power facility for electric railways - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic shield type DC power facility for electric railways, and more particularly to a magnetic flux density around the facility due to the current of both cables in a DC power facility having a forward cable and a reverse cable for supplying DC power. Restrained electric railway
For magnetic shield type DC power facilities for automobiles.

[0002]

2. Description of the Related Art Referring to FIGS. 1 and 2, in a substation facility 11 of a DC type train line 14, a high voltage AC power is received and a transformer is used to reduce the voltage to a voltage suitable for the train line and a silicon rectifier. The DC power is supplied to the train line 14 via the forward cable 1 and the reverse cable 2 after being converted into direct current by the above method. In the figure, direct current is supplied to the trolley wire 15 and feeder 16 via the forward cable 1, and the current supplied from the pantograph to the train 19 is returned from the wheels of the train 19 to the return cable 2 via the rails 18. .

For example, in a DC type train line 14 in a metropolitan area, the trolley line 15 and the rail 18 are about 500 to 1,000 in the daytime.
A, a large DC current of over 2,000-3,000A flows during rush hour. For this reason, a magnetic field is generated around the train line 1 due to the forward current of the trolley wire 15 and the feeder line 16 and the return current of the rail 18, and also around the substation facility 11, the forward current of the forward cable 1 and the return current. A magnetic field is generated by the return current of the cable 2.

At a place sufficiently distant from the train track 1 and the substation facility 11, the magnetic fields due to the forward current and the backward current are so small as to be practically negligible due to the distance attenuation characteristic. However, the magnetic field has a non-negligible value near the train line 1 and the substation facility 11, and if an electron beam utilizing device such as a CRT exists at that place, the electron beam inside the device is undesired due to the surrounding magnetic field. Magnetic interference (hereinafter referred to as magnetic interference) such as distortion, color shift, or other disorder in an image caused by deflection has been experienced. Also, MR
I (Magnetic Resonance Imaging), pacemakers, and other medical devices and precision electronic devices may malfunction.

Conventionally, as a countermeasure against such magnetic interference, medical equipment, precision electronic equipment and the like (hereinafter referred to as electromagnetic equipment) affected by a magnetic field are covered with a magnetic shielding material so as not to be affected by the magnetic field. Passive shielding methods are in place.

[0006]

However, in the conventional passive shielding method, the handling of the device becomes inconvenient, the commercial design of the device itself is impaired, and a large amount of magnetic shielding is present in the presence of a strong ambient magnetic field. There is a problem that the material is required and it becomes heavy and inconvenient to carry.

In addition, a new substation facility 11 is newly installed adjacent to the elevated train due to the double-track construction of the subway line 14, and the reciprocating cables 1, 2 from the substation facility 11 to each subway line on the elevated line.
May be laid. Since a large DC current (for example, 3000A x 4) for multiple lines flows through the reciprocating cables 1 and 2 of such a substation facility at the time of rush, the substation facility 1
Magnetic interference may occur in a private house or medical institution adjacent to 1. In such a substation facility 11 in a metropolitan area, it is desired to develop an active shielding method capable of suppressing the magnetic flux density generated in the surroundings, instead of the conventional passive shielding method.

[0008] Therefore, an object of the present invention is to provide a magnetic shield type DC power facility for electric railways in which the magnetic flux density around the facility is suppressed.

[0009]

With reference to the embodiments of FIGS. 1 and 2, a magnetically shielded DC power facility for electric railway according to the present invention is provided with a connection to a power supply device 22 or a load, respectively. In a DC power facility having a cable 1 and a return cable 2, predetermined portions of the forward cable 1 and the return cable 2 are juxtaposed side by side to cancel the magnetic fields due to the currents of the cables 1 and 2, and the forward cable 1 and / or the return cable 2 Surround the required parts of the parts that are not juxtaposed with each other with the duct 3 made of magnetic shield material
Only , the magnetic flux density around the facility due to the currents of the outgoing cable 1 and the returning cable 2 is suppressed.

Preferably, the duct 3 as shown in FIG.
In addition, a gutter member 4 in which a plurality of magnetic shield plates 6 formed by laminating high-permeability steel plates are magnetically coupled in a U-shaped cross section.
And a lid member 5 consisting of a magnetic shield plate 6 and detachably magnetically coupled to the opening of the gutter member 4. Magnetically coupling means coupling so that magnetic fluxes can pass through each other. More preferably, as shown in FIG. 4, the duct 3 is provided with a heat radiating slit 10 that extends in a direction perpendicular to the cable length direction.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment in which the present invention is applied to a substation facility 11 (hereinafter referred to as a DC power facility for electric railways) provided below a viaduct 12 of an elevated railway. In the figure
In the DC power facility 11 for electric railway, for example, a silicon rectifier
Forward cable 1 (plug
One side) to connect as a connection part, and the forward cable 1
Connect the other end of the
Supply power. In addition, restore to the other output terminal of the power supply unit 22.
Connect one end of cable 2 (minus side) as a connection part,
Connect the other end of the recovery cable 2 to the rail 18 to generate electric current.
Return to source device 22. Feeder 16 and rail 18 are loads
A forward line and a return line of the train 19 which are separated from each other are formed.

The forward current of the forward cable 1 and the backward current of the backward cable 2 each form a magnetic field around the DC power facility 11, but by arranging the forward cable 1 and the backward cable 2 in close proximity, both cables 1, 2 The magnetic field due to the current can be canceled out, and the magnetic flux density around the facility can be suppressed to the extent that electromagnetic equipment is not disturbed. Reference numeral 21 in FIG. 1 indicates a normal cable duct that surrounds both cables 1 and 2 that are juxtaposed.

However, it may be difficult to place the forward cable 1 and the backward cable 2 in close juxtaposition in all parts. When the feeder line 16 on the load side and the rail 18 are separated from each other as in the illustrated example, it is necessary to separate the forward cable 1 and the return cable 2 which are juxtaposed to each other at least immediately before the load. In the portion where the cables 1 and 2 are not juxtaposed, in this case, the portion from the rail 18 to the feeder 16 cannot cancel the magnetic field due to the current of the cables 1 and 2.

According to the present invention, a required portion of the forward cable 1 and / or the backward cable 2 which is not juxtaposed is surrounded by a duct 3 made of a magnetic shield material. FIG. 2 shows the duct 3 made of the magnetic shield material of FIG. 1 as seen from above the slab of the viaduct 12. In the illustrated example, a soundproof wall 20 extending in the length direction of the track is provided on one or both sides of the railway track of the viaduct 12, but in FIG.
A part of 20 is cut out and shown.

In the example of FIGS. 1 and 2, since there is no private house adjacent to the part of the return cable 2 which is not arranged in parallel, only the part from the rail 18 of the outward cable 1 to the feeder 16 is covered with the duct 3 made of the magnetic shield material. Surrounded . However, if necessary, the duct 3 made of the magnetic shield material may be provided in a portion where the return cable 2 is not arranged in parallel.

The cable is connected to the duct 3 made of magnetic shield material.
If the enclosure and the path of the magnetic flux (hereinafter referred to as the magnetic path) are formed, the magnetic flux generated from the cable is concentrated in the magnetic path,
The magnetic flux spreading to the outside of the duct 3 can be suppressed. The present inventor conducted experiments to construct the duct 3 with the magnetic shield plate 6 formed by stacking high-permeability magnetic steel sheets, even if a DC current of 2,000 to 4,000 A flows through the cables 1 and 2. It was confirmed that the magnetic flux density outside 3 can be suppressed to about 1/3 to 1/5 as compared with the case where the duct 3 is not provided.

[0017]

[Table 1]

However, the duct 3 made of a magnetic shield material is not limited to the duct made of an electromagnetic steel plate, and the magnetic characteristics and structure of the magnetic shield material can be selected according to the level of suppression of the magnetic flux density required around the facility. For example, the magnetic characteristics of the magnetic shield material are selected from the magnetic materials shown in Table 1,
Furthermore, the thickness of each layer and the number of layers of the magnetic shield material having a multi-layer structure can be selected according to the suppression level. It is said that the magnetic shield effect will be enhanced when the ferromagnetic layers are multilayered while providing an appropriate space ("Architectural Institute of Japan" Measurement technology of environmental magnetic field "July 15, 1998, p11-1).
2).

According to the present invention, the magnetic flux density around the DC power facility can be suppressed to such an extent that the electromagnetic equipment is not damaged. In addition, duct 3 made of magnetic shield material
It is possible to make the magnetic flux density around the facility below the allowable value within a certain limit by appropriately selecting the magnetic characteristics and structure of the.

Thus, the object of the present invention is to provide the "magnetic shield type DC power facility for electric railways capable of suppressing the magnetic flux density around the facility".

Although the example in which the duct 3 made of the magnetic shield material is provided in the portion connecting the reciprocating cables 1 and 2 to the load has been described above, the reciprocating cable is also provided inside the DC power facility 11 due to the arrangement of machines. There may be places where 1 and 2 cannot be juxtaposed. For example, the example of FIG. 1 is a case where the positive connection portion and the negative connection portion of the power supply device 22 are separated from each other. When the facility 11 is close to a private house, magnetic shielding from the reciprocating cables 1 and 2 inside the facility may pose a problem.

In FIG. 1, reciprocating cables 1, 2 inside the facility are shown.
The magnetic flux density around the facility is suppressed by providing the duct 3 made of the magnetic shield material also in the portions that cannot be juxtaposed side by side. Note that it is not necessary to enclose all the portions of the reciprocating cables 1 and 2 that are not juxtaposed side by side with the duct 3 made of the magnetic shield material, and it is sufficient to enclose the required part where suppression of the magnetic flux density around the facility is required with the duct 3 made of the magnetic shield material. .

[0023]

EXAMPLE FIG. 3 shows an example of a duct 3 made of a magnetic shield material used in the present invention. The duct 3 in the figure is, for example, 0.
Three magnetic shield plates 6 made by laminating 2 to 0.5 mm high-permeability steel plates to a thickness of about 30 to 50 mm are magnetically coupled in a U-shaped cross section with a magnetic shielding joint or joint cover plate 7. The gutter member 4 and the lid member 5 which is composed of the magnetic shield plate 6 and is detachably magnetically coupled to the opening of the gutter member 4 by the bolt 9. At the opening of the gutter member 4, a magnetic shielding joint portion or a seam cover plate 7 is attached to prevent leakage magnetic flux from the gap when the gutter member 4 is coupled to the lid member 5. The shape of the cover plate 7 is flat, L
A shape or other suitable shape can be used according to the shape of the duct 3. Reference numeral 8 in the drawing denotes an angle member for fixing the lid member 5 with the bolt 9.

The duct 3 in FIG. 3 can be carried in, for example, in a disassembled state, and can be easily assembled at a portion where the reciprocating cables 1 and 2 need to be shielded. Further, by making the lid member 5 removable, it is possible to facilitate the work at the time of assembly and cable exchange. An example of a method of attaching the duct 3 to the cables 1 and 2 is to reinforce the rigidity of the duct 3 if necessary, and then attach the gutter member 4 of the duct 3 to the duct frame body 3a supported around the cables 1 and 2. It is fixed (see FIG. 2). As a rust preventive measure for the magnetic shield plate 6, it is desirable to appropriately provide a rust preventive layer on the surface of the duct 3 by painting or coating.

FIG. 4 shows an embodiment in which the magnetic shield plate 6 of the duct 3 is provided with a heat radiating slit 10 in a direction perpendicular to the cable length direction. The magnetic shield plate 6 that covers the cable does not necessarily need to be continuous, and even when a proper slit is provided in the direction orthogonal to the cable length direction, the magnetic path is less interrupted than in the case where it is continuous, and the shielding performance is improved. Since the duct 3 does not show a significant decrease, it is possible to avoid overheating of the cable in which a large DC current flows, especially when the duct 3 is provided with a high temperature in the summer.

The magnetic shield material duct 3 shown in FIGS. 3 and 4 may be applied to a segment member when a shield is constructed, for example, by combining it with an appropriate support structure, and is used as a magnetic shield duct for a subway feeder. You can also expect to do it.

[0027]

As described above, the magnetically shielded DC power facility for electric railway according to the present invention is configured so that the forward and backward cables of the DC power facility are arranged in close proximity to each other and the current of both cables is increased. By canceling the magnetic field due to, and enclosing the required portion of the forward cable and / or the backward cable, which are not juxtaposed side by side, with a duct made of a magnetic shield material, the following remarkable effects are obtained.

(A) It is possible to suppress the magnetic flux density around the electric power facility for electric railways, prevent the occurrence of magnetic interference around the facility, and contribute to the reduction of the excessive magnetic flux density around the existing facility. (B) By selecting the magnetic characteristics and structure of the magnetic shield material, it is possible to keep the magnetic flux density around the facility within an allowable value within a certain limit. (C) The magnetic shield material duct has a structure in which one side surface is removable, so that the work for replacing or adding a cable can be facilitated. (D) By providing a heat dissipation slit in the duct at a right angle to the length direction of the cable, it is possible to avoid overheating of the cable when the temperature is high in summer.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing details of the duct made of the magnetic shield material of FIG. 1.

FIG. 3 is an explanatory diagram of an example of a duct made of a magnetic shield material.

FIG. 4 is an explanatory view of another example of the magnetic shield material duct.

[Explanation of symbols]

1 ... Forward cable 2 ... Forward cable 3 ... Duct made of magnetic shield material 3a ... Frame body 4 ... Gutter member 5 ... Lid member 6 ... Magnetic shield plate 7 ... Cover plate 8 ... Angle member 9 ... Bolt 10… Heat dissipation slit 11… DC power facility 12… Viaduct 14… Train track 15 ... Trolley wire 16 ... Feeder wire 17 ... Chair line 18 ... Rail 19 ... Train 20 ... Soundproof wall 21 ... Cable duct 22 ... Power supply

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Go Tanabe 1-2-7 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd. (56) Reference JP-A-8-293578 (JP, A) JP-A 11-61704 (JP, A) Actual development Sho 62-74444 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02J 1/00-1/06 E01B 26/00 H02G 9 / 04 B60M 1/06

Claims (6)

(57) [Claims] 1. In a DC power facility for electric railway having a forward cable and a return cable, each of which is provided with a connecting portion to a power supply device or a load, a predetermined portion of the forward cable and the return cable are juxtaposed in close proximity to each other. The magnetic field due to the electric current is canceled out, and the required portion of the forward cable and / or the return cable which is not juxtaposed is surrounded by a duct made of a magnetic shield material.
See, railway magnetic shielding direct-current power facilities for obtained by suppressing the magnetic flux density of the surrounding facilities by currents of the forward cable and recovery cable. 2. The gutter member according to claim 1, wherein a plurality of magnetic shield plates formed by laminating high-permeability steel plates are magnetically coupled to each other in a U-shaped cross section in the duct, A magnetically shielded DC power facility for electric railway, comprising a magnetic shield plate and a lid member detachably and magnetically coupled to the opening of the gutter member. 3. A DC power facility according to claim 2, magnetic shielding for railway comprising a stack of the magnetic shield plate steel with high magnetic permeability in the thickness 0.2~0.5mm thickness of about about 30~50mm Type DC power facility. 4. In any of the DC power facilities of claims 1 to 3, magnetic shielding direct-current power facilities for railway formed by providing the heat radiation slits of the cable length direction perpendicular orientation to said duct. 5. The DC power facility according to any one of claims 1 to 4, wherein the connecting portions of the outgoing cable and the returning cable are connected to the outgoing line and the returning line of the load, which are separated from each other, and A magnetically shielded DC power facility for electric railway in which required portions of the forward cable and / or the backward cable that are not juxtaposed close to each other immediately before the return line are surrounded by the duct made of the magnetic shield material. 6. The DC power facility according to claim 5, wherein the forward line and the return line of the load are used as feeders and rails of a DC type train line, and the power facility is provided adjacent to the train line. Magnetically shielded DC power facility for electric railways.