JPH0620561A - Disconnecting switch equipped with resistance - Google Patents

Abstract

PURPOSE:To provide a disconnecting switch having an excellent resistance, including a small, simple resistor, and capable of contributing to miniaturization and simplification, of overall equipment and securing the electrical and mechanical reliability of the resistor over a sufficiently long time from the stage of manufacture after operation. CONSTITUTION:In a sealed container 1 having an insulating medium sealed therein, a movable contact portion 2 and a fixed contact portion 3 are disposed coaxial with each other and a movable contact 4 is disposed between the contact portions. A resistor shield 7 is disposed around the fixed contact portion 3 and is connected to the fixed contact portion 3 through a resistor 9. An electric circuit is opened and closed by control of the movable contact 4. The resistor 9 comprising resistance wires 15a, 15b molded from epoxy resin 16 and metal fittings 17 embedded or driven into the ends thereof is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disconnector with a resistor used in a substation, and more particularly to a structure of a resistor.

[0002]

2. Description of the Related Art Generally, a gas-insulated switchgear is used for a circuit breaker, a disconnector, a grounding switch, a current transformer, and an instrument in an airtight container filled with an insulating medium such as SF ₆ gas at about 3 to 6 atmospheres. It is configured to house the equipment required for opening and closing operations such as transformers. Among these devices, the opening / closing operation of the disconnector is usually performed with the breaker opened. Along with such switching operation of the disconnecting switch, a surge called disconnecting switch surge is generated between the poles of the disconnecting switch and propagates in the gas insulated switchgear. This disconnector surge is gas insulated switching in the UHV class. Since it becomes large enough to threaten the insulation of the device, some measures must be taken.

Conventionally, for the purpose of suppressing the voltage level of the disconnecting switch surge, a disconnecting switch with resistance of the type schematically shown in FIG. 2 has been considered.
As shown in this figure, a movable side contact portion 2 and a fixed side contact portion 3 are provided in a tank 1 filled with an insulating medium such as SF ₆ gas.
Are arranged on a coaxial line, and the movable contactor 4 is disposed between the contact portions 2 and 3, and the movable contactor 4 linearly slides in the axial direction of the contact portions 2 and 3, It is configured to open and close the disconnector. That is, fingers 5 and 6 that come into contact with the movable contact 4 are provided on the inner peripheral portions of the movable contact 2 and the fixed contact 3, respectively. While being constantly in contact with the finger 5 of No. 3, the finger 6 of the fixed side contact portion 3 can be brought into contact with and separated from the finger 6.

A resistor shield 7 for mitigating an electric field is arranged around the fixed side contact portion 3, and between the movable contact 4 and the resistance contact 8 of the resistor shield 7 when the disconnector is turned on. To have a gap g. This gap g is used when the re-ignition occurs between the disconnector poles at the time when the tip of the movable contactor 4 is located near the resistance contact 8 during the opening / closing operation of the disconnector. Is energized by flashover, and at this time, the movable contactor 4 and the fixed side contact portion 3 and the tank 1 are determined by conducting a study from the viewpoint of insulation coordination so as not to cause dielectric breakdown. Further, the resistor shield 7 has a resistor 9 having a value capable of sufficiently suppressing the disconnector surge.
It is connected to the fixed side contact portion 3 via. During the opening / closing operation of the disconnector, re-ignition occurs a plurality of times between the movable contactor 4 and the resistance contact 8, but the disconnector surge level at this time is sufficiently suppressed by the resistor 9. The material and structural aspects of the resistor 9 are currently being studied.

Further, it is considered that ceramics are used as the resistor 9 of the disconnecting switch with resistance of the above-mentioned system. FIG. 6 is a configuration diagram showing an example of such a conventional ceramic resistor, and FIG. 7 is a plan view showing an example of the arrangement configuration of the ceramic resistor of FIG.

First, as shown in FIG. 6, the ceramic resistor 21 is formed by laminating a plurality of ring-shaped resistors 21a and penetrating an insulating bolt 21b in the hollow portion thereof. Then, one end of this insulating bolt 21b is attached to the resistor shield 7, and the other end is fixed side contact portion 3
The ceramic resistor 21 and the resistor shield 7 are supported by the fixed contact portion 3 by being attached to the fixed contact portion 3. In this case, as shown in FIG. 7, a plurality of ceramic resistors 21 are arranged at the outer peripheral side end of the resistor shield 7 at equal intervals (four in the figure as an example).

Further, since the mechanical strength of the insulating bolt 21b is relatively weak, the strength is compensated for by the ceramic resistor 2
As shown in FIG. 7, a plurality of insulating rods 22 are arranged in parallel with the ceramic resistor 21 for the purpose of surely supporting 1 and the resistor shield 7 with respect to the fixed side contact portion 3, and at both ends thereof. And is attached to the resistor shield 7 and the fixed side contact portion 3. In this case, in the example of FIG. 7, one insulating rod 22 is provided between the adjacent ceramic resistors 21.
Are arranged. That is, in the example of FIG. 7, four ceramic resistors 21 and four insulating rods 22 are arranged between the resistor shield 7 and the fixed side contact portion 3,
Each of them is attached to the resistor shield 7 and the fixed side contact portion 3 at both ends thereof.

[0008]

By the way, when the above ceramic resistor is used as the resistor of the disconnector with resistance, as described above, the mechanical strength is compensated for by the ceramic resistor 21 and the resistor. In order to securely support the body shield 7 with respect to the fixed-side contact portion 3, as shown in FIG. 7, a plurality of (four as an example in the figure) insulating rods 22 are arranged in parallel with the ceramic resistor 21. There is a need to. As a result, a large number of ceramic resistors 21 and insulating rods 22 are arranged in the space between the resistor shield 7 and the fixed-side contact portion 3, as shown in FIG. Will turn into.

Further, since the disconnecting switch is a device that involves mechanical operation, it is conceivable that a large mechanical vibration will be generated due to the opening and closing operation, and that the operation will occur frequently.
Such mechanical vibration is caused by the insulating bolt 21b forming the ceramic resistor 21 and the ring-shaped resistor 2 having a plurality of layers.
In addition to 1a, as the number of times of operation increases, problems such as loosening of the insulation bolt 21b and separation of the resistors 21a may occur, and the electrical and mechanical characteristics of the ceramic resistor 21 may deteriorate. is there.

The present invention was proposed in order to solve the above-mentioned problems of the prior art, and the purpose thereof is to provide a small and simple resistor to contribute to the miniaturization and simplification of the entire device. It is an object of the present invention to provide an excellent disconnecting switch with resistance, which can sufficiently secure the electrical and mechanical reliability of the resistor for a long period from the manufacturing stage to after the operation.

[0011]

In the disconnector with resistance according to the present invention, a movable side contact portion and a fixed side contact portion are arranged on a coaxial line in an airtight container in which an insulating medium is sealed, and the movable side contact portion is provided. A movable contact is disposed between the fixed contact portion and the fixed contact portion, and a resistor shield is disposed around the fixed contact portion, and the resistor shield is connected to the fixed contact portion via a resistor. In the disconnector with resistance having the structure described above, which opens and closes an electric circuit by operating the movable contactor, the resistor body casts a resistance wire with an epoxy resin, and a metal fitting at its end. It is characterized in that it is configured by embedding or screwing.

Further, specifically, the main body of the resistor is formed by casting two resistance wires, which are wound in opposite directions (non-inductively), with an epoxy resin. Furthermore, a coated resistance wire is used as the resistance wire, and can be wound in a close contact state. In the usual case, a plurality of resistors are arranged at equal intervals around the fixed-side contact portion, and typically three resistors are arranged.

[0013]

In the present invention having the above-mentioned structure, the mechanical strength of the resistor, that is, the resistance wire, is embedded in the epoxy resin portion that molds it and the end portion of this epoxy resin portion, or Secured by screwed metal fittings. Therefore, sufficient mechanical reliability can be obtained only by the structure of this resistor, and the resistor itself and the resistor shield can be supported, so that it is not necessary to dispose a reinforcing insulating rod in the vicinity of the resistor. Further, even when a large mechanical vibration is generated due to the opening / closing operation, it is possible to withstand a large mechanical load applied to the resistor. Further, since the metal fittings arranged at the ends of the molded epoxy resin portion can be used to easily support the resistor shield and connect the resistance wires, electrical reliability can be ensured. it can.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A plurality of embodiments of the disconnecting switch with resistance according to the present invention will be specifically described below with reference to the drawings.

(1) First Embodiment FIG. 1 to FIG. 4 FIG. 1 is a structural view showing a first embodiment of a disconnecting switch with resistance according to the present invention, FIG. 3 is a view taken in the direction of arrow A in FIG. FIG. 3 is a configuration diagram showing the resistor of FIG. 1. The method of the disconnecting switch with resistance of the present embodiment shown in these drawings is the same as the method of the disconnecting switch with resistance of FIG. 2 described above. First, as shown in FIG. 1, SF ₆
In a tank (closed container) 1 filled with an insulating medium such as gas, a movable contact part 2 and a fixed contact part 3 are arranged coaxially in the vertical direction, and a movable contact is made between the contact parts 2 and 3. The child 4 is arranged, and the movable contactor 4 has contact portions 2, 3
The disconnector is opened and closed by linearly sliding in the axial direction. This movable contact 4
Is operated via an opening / closing mechanism 11 by an operating device 10 attached to the upper part of the tank 1. That is, the rotational driving force of the operating device 10 is configured to be converted from the rotational movement to the linear movement by the opening / closing mechanism 11 and transmitted to the movable contactor 4.

Further, the resistor shield 7 is arranged between the movable side contact portion 2 and the fixed side contact portion 3, and a resistance contact 8 is provided at the inner peripheral side end portion thereof. The resistance contact 8 is configured to face the movable contact 4 via the gap g in the closed state. On the other hand, a plurality of downwardly extending resistors 9 are attached to the lower part of the outer peripheral side end of the resistor shield 7, and the lower end of the resistor 9 is attached to the connecting part 3 a of the fixed side contact part 3. Has been. Further, the movable side contact portion 2 and the fixed side contact portion 3 are respectively supported by the insulating cylinder 12 with respect to the upper and lower ends of the tank 1.
In addition, the connection conductors 13 are respectively led out in the horizontal direction from the side surfaces of the movable side contact portion 2 and the fixed side contact portion 3 and are drawn out to the outside by the insulating spacer 14.

More specifically, as shown in FIG. 3, at the lower portion of the outer peripheral side end portion of the resistor shield 7, three downwardly extending resistors 9 are arranged at equal intervals around the fixed side contact portion 3. It is arranged. As shown in FIG. 4, the main body of the resistor 9 has
Two resistance wires 15 wound in opposite directions (without induction)
It is formed by casting the whole of a and 15b with an epoxy resin. In the figure, 16 indicates the epoxy resin portion 16 formed in this way. In this case, the resistance wire 15
Insulating coating is applied to a and 15b, and the resistance wire 15
A and 15b are wound in close contact with each other.

Further, metal fittings 17 are arranged at both ends of the main body of the resistor 9 thus molded with epoxy resin so as to be embedded in the epoxy resin part 16. The metal fitting 17 has screws 18 at both ends of the resistance wires 15a and 15b.
Tightened by the metal fitting 17 and the resistance wires 15a, 15
b is electrically and mechanically connected. In addition, metal fittings 1
A threaded portion 17a is provided at both ends of 7, and is fastened to the resistor shield 7 and the connecting portion 3a of the fixed side contact portion 3 by the threaded portion 17a and a bolt 19a.
That is, the metal fittings 17 at both ends of the resistor 9 are
The bolt 19a is inserted from the opposite surface of the resistor shield 7 and the connecting portion 3a in a state of contacting the lower surface of the resistor shield 7 and the upper surface of the connecting portion 3a, and the metal fitting 17 is inserted through the resistor shield 7 and the connecting portion 3a. The resistor 9 is attached to the resistor shield 7 and the connecting portion 3a of the fixed-side contact portion 3 by being screwed into the screw portion 17a.

In the present embodiment having the above-mentioned structure, since the resistor 9 is formed by casting the resistance wires 15a and 15b in the epoxy resin, the epoxy resin portion 16 improves the mechanical strength. Conventional ceramic resistor 21
A sufficiently high mechanical strength can be obtained as compared with. That is,
Epoxy resin casting is a highly promising technology at this stage, and the resistance wires 15a, 15
By mechanically casting resistor b while winding b on metal fitting 17 to produce resistor 9, mechanically strong resistor 9 can be obtained.

Therefore, since the resistor 9 itself and the resistor shield 7 can be supported only by the resistor 9, the insulating rod 2 required when the ceramic resistor 21 is used.
2 is unnecessary, and the size of the resistor 9 itself can be remarkably reduced as compared with the ceramic resistor 21.
The configuration around the resistor 9 can be remarkably reduced in size and simplified as compared with the conventional one. Further, the resistor 9 is attached to the resistor shield 7 and the connecting portion 3a of the fixed side contact portion 3 by the resistor 9
Since the metal fittings 17 and the bolts 19a provided at both ends of the resistor 9 are used, electrical and mechanical connection between the resistor 9 and the resistor shield 7 and the connecting portion 3a of the fixed-side contact portion 3 is performed easily and reliably. be able to.

As described above, in this embodiment, the resistor 9 itself has a high mechanical strength, and the resistor 9 and the resistor 9 are connected to each other by the metal fittings 17 and the bolts 19a provided at both ends of the resistor 9. Connection part 3 of body shield 7 and fixed side contact part 3
Since a and a can be firmly fixed to each other, the mechanical strength of the entire periphery of the resistor 9 can be significantly improved as compared with the conventional case. Therefore, even when a large mechanical vibration is generated due to the opening / closing operation, there is a problem such as looseness in the conventional ceramic resistor 21 which is composed of a plurality of layers of the ring-shaped resistor 21a and the insulating bolts 21b. There is no fear of occurrence, and a large mechanical load applied around the resistor 9 can be sufficiently endured. Further, in this embodiment, since three resistors 9 are arranged at equal intervals, there is also an advantage that the support structure is well balanced.

(2) Second Embodiment FIG. 5 FIG. 5 is a constitutional view showing a resistor used in a second embodiment of the disconnector with resistance according to the present invention. As shown in FIG. 5, in this embodiment, the main body of the resistor 9 is the first
Similar to the embodiment, two resistance wires 15a having an insulating coating,
Winding 15b in close contact with each other in opposite directions (without induction),
The entire two resistance wires 15a and 15b are formed by casting with an epoxy resin.

In the present embodiment, the threaded portions 16a are provided at both ends of the epoxy resin portion 16, and the metal fitting 20 having the threaded portions 20a corresponding to the threaded portions 16a is provided.
However, it is screwed by applying an adhesive. This metal fitting 20
A hole 20b is formed at the center of the hole 20b.
The ends of the resistance wires 15a and 15b are passed through. Further, the ends of the resistance wires 15a and 15b are connected to the end surface 20 of the metal fitting 20.
The metal fitting 20 and the resistance wires 15a and 15b are electrically and mechanically connected to each other by the screw 18 on the c.

The metal fitting 20 has a screw portion 20 which can be fastened to the resistor shield 7 and the connecting portion 3a of the fixed side contact portion 3.
d is provided, and the screw portion 20d and the nut 19b are provided.
Are fastened to the resistor shield 7 and the connecting portion 3a of the fixed side contact portion 3. That is, the threaded portions 20d of the metal fittings 20 at both ends of the resistor 9 are respectively inserted so as to penetrate the resistor shield 7 and the connecting portion 3a and project to the opposite surface thereof, and the nuts 19b are respectively attached to the projecting portions. By being screwed in, the resistor 9 is attached to the resistor shield 7 and the connecting portion 3 a of the fixed-side contact portion 3.

In the present embodiment having the above-described structure, the resistor 9 is formed by casting the resistance wires 15a and 15b in an epoxy resin as in the above-described embodiment, and therefore the epoxy resin portion 16 is used. The mechanical strength is improved, and sufficiently higher mechanical strength can be obtained as compared with the conventional ceramic resistor 21. Therefore, similarly to the above-described embodiment, the structure around the resistor 9 can be remarkably downsized and simplified as compared with the conventional structure.

Since the resistor shield 7 and the fixed side contact portion 3 are attached to the connecting portion 3a by the metal fittings 20 and the nuts 19b attached to both ends of the resistor 9, the resistor 9 and the resistor shield are attached. It is possible to easily and surely perform electrical / mechanical connection with the connection portion 3a of the stationary side contact portion 3 and the fixed side contact portion 7. In this case, the metal fitting 20 should be attached to the main body of the resistor 9 by using the epoxy resin portion 1
In addition to fastening the threaded portion 16a provided on the screw 6 and the threaded portion 20a of the metal fitting 20 by using an adhesive, the metal fitting 20 can be firmly fixed, and the mechanical reliability of this portion can be improved. Is high.

As described above, in the present embodiment, the resistor 9 itself has high mechanical strength, and the resistor 9 and the resistor 9 are connected to each other by the metal fittings 20 and the nuts 19b provided at both ends of the resistor 9. Connection part 3 of body shield 7 and fixed side contact part 3
Since a and a can be firmly fixed to each other, the mechanical strength of the entire periphery of the resistor 9 can be significantly improved as compared with the conventional case. Therefore, even when a large mechanical vibration is generated due to the opening / closing operation, there is no possibility of causing a problem such as loosening as in the conventional ceramic resistor 21, and the resistor 9 is similar to the first embodiment. It can sufficiently withstand a large mechanical load applied to the periphery.

(3) Other Embodiments The present invention is not limited to the above-mentioned embodiments. For example, as the resistance wire of the resistor, use is made of a resistance wire without insulation coating. Is also possible. Further, the number of resistors used is not limited to three,
It can be appropriately selected. Further, the specific configuration of the metal fitting arranged at the end of the resistor can be selected as appropriate.

[0029]

EFFECTS OF THE INVENTION According to the present invention, by using a small and simple resistor in which a resistance wire is cast with an epoxy resin and a metal fitting is embedded or screwed into the end thereof, It is possible to provide an excellent disconnector with resistance, which can contribute to simplification and can sufficiently secure the electrical / mechanical reliability of the resistor for a long period from the manufacturing stage to after the operation.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a disconnecting switch with resistance according to the present invention.

FIG. 2 is a schematic diagram showing a method of the disconnecting switch with resistance of FIG.

FIG. 3 is a view on arrow A in FIG.

FIG. 4 is a configuration diagram showing the resistor of FIG.

FIG. 5 is a configuration diagram showing a second embodiment of a disconnecting switch with resistance according to the present invention.

FIG. 6 is a configuration diagram showing an example of a ceramic resistor used in a conventional disconnector with resistance.

FIG. 7 is a plan view showing an example of the arrangement configuration of the ceramic resistors of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tank (sealed container) 2 ... Movable side contact part 3 ... Fixed side contact part 3a ... Connection part 4 ... Movable contactor 7 ... Resistor shield 8 ... Resistive contact 9 ... Resistor 10 ... Operating device 11 ... Opening / closing mechanism 12 Insulation cylinder 13 Connection conductor 14 Insulation spacer 15a, 15b Resistance wire 16 Epoxy resin part 16a Screw part 17 Metal fitting 17a Screw part 18 Screw 19a Bolt 19b Nut 20 Metal fitting 20a Screw part 20b ... hole 20c ... end face 20d ... screw part 21 ... ceramics resistor 21a ... resistor 21b ... insulating bolt 22 ... insulating rod

Claims (2)

[Claims] 1. A movable side contact portion and a fixed side contact portion are coaxially arranged in a sealed container in which an insulating medium is sealed, and a movable contact is provided between the movable side contact portion and the fixed side contact portion. The movable contactor has a structure in which a resistor shield is disposed around the fixed contact portion, and the resistor shield is connected to the fixed contact portion via a resistor. In a disconnector with resistance for opening and closing an electric circuit by operating, a resistor is characterized in that the resistor is made by casting a resistance wire with epoxy resin and embedding metal fittings at its end. Disconnector. 2. A movable container and a stationary contact are coaxially arranged in a sealed container containing an insulating medium, and a movable contact is provided between the movable contact and the stationary contact. A resistor shield is disposed around the fixed-side contact portion, the resistor shield is connected to the fixed-side contact portion via a resistor, and the movable-side contact portion and the fixed-side portion are connected to each other. In a disconnector with a resistor that has a structure in which connection conductors are respectively led out from the contact portion and that opens and closes an electric circuit by operating the movable contactor, the resistor is a resistor wire filled with epoxy resin. A disconnecting switch with resistance, characterized in that it is formed by molding a metal fitting and screwing it into the end.