JPH08168124A - Switchgear - Google Patents

Abstract

PURPOSE: To provide a small-sized reliable switchgear comprising standardized parts. CONSTITUTION: At least three sets of bushings 5-7 for a main circuit and bushings 8-10 for grounding are arranged at the bottom of a container 4 for insulating gas. Support conductors 11-13, vacuum interrupters 1-3, ring contacts 17-19, an insulating rod, etc., are arranged linearly at the upper portion of the bushings 5-7 for main circuit and the upper edge is connected by an operation mechanism. The ring contacts 17-19 in phase within each set are connected by a connection conductor. A fixing contact is mounted to the support conductors 11-13, a movable plate which contacts and leaves them is mounted to the upper portion of the bushings 8-10 for grounding so that it can be rotated, thus constituting a grounded switchgear. A cable room is provided at the lower portion of a container 4 and at least one set of power cable and two sets of power cable are drawn for a load side and a power-receiving side, respectively, and are connected to the bushings 5-7 for main circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switchgear installed at a power receiving point for supplying power from a loop system to a load.

[0002]

2. Description of the Related Art A loop power receiving system is one of power receiving systems for receiving power from a load from a certain point of a loop system, and a circuit configuration is a T-branch circuit as shown in FIG. That is, one set of circuit breaker (CB) 71 and two sets of load switch (LBS) 7
One end of 2, 73 is connected in common, the other end of the circuit breaker 71 is connected to the load via the disconnector 74, and the other ends of the load switches 72, 73 are connected to the loop system. Load switch 7
Since 2 and 73 and the disconnecting switch 74 are provided with a grounding mechanism, a three-position type switch that can be set to three states of main circuit closed, neutral, and main circuit grounding is used. The load switch is generally used in combination with a power fuse.

In this type of power circuit, it is common to use a switchgear in which a plurality of switches are housed in a container in which an insulating gas is sealed. The outline of the switchgear is shown in FIGS. 9 shows. In the figure, 70 is a container in which an insulating gas is enclosed, 71 is a circuit breaker (for example, a vacuum interrupter), 72
Reference numerals 73 and 73 are load switches having a grounding mechanism, and 74 is a disconnecting switch having a grounding mechanism. Insulating frame 7 on the bottom of container 70
5 is arranged, and the support conductor 76 is mounted thereon.
A vacuum interrupter 71, an insulating plate 77, on the support conductor 76,
The ring contact 78 and the insulating rod 79 are linearly arranged, and the operation mechanism 80 including a trip spring is connected to the upper end of the ring contact 78 and the insulating rod 79. A conductive support plate 81 is attached around the ring contact 78, and a fixed contact 74A of the disconnector 74 with a three-position type grounding mechanism is arranged thereon. On both sides of the support conductor 76, there are load switches 72, 7 with a grounding mechanism.
Three fixed contacts 72A and 73A are attached.
Movable blades 72B and 73B of load switches 72 and 73
Are rotatably supported on upper portions of bushings 82, 83 on the power receiving side arranged on the bottoms of the containers on both sides of the insulating frame 75. In addition, a bushing 84 on the load side is arranged on the bottom of the container 4 on the back side, and the movable blade 7 of the disconnector 74 and the upper part thereof are arranged.
The terminal on the 4B side is connected by a connecting conductor 85. A cable chamber 86 is provided below the container 70 so that the bushings 82 to 84 and the power cable are internally connected.

There is a switchgear (Japanese Patent Application No. 4-313844 "Insulating switchgear") which is provided with means for reducing the influence of arced gas generated when the load switchgear is opened and closed.

[0005]

As described above, a plurality of switches, that is, a pair of vacuum interrupters 71 and 2 are provided in the container 70.
When a pair of load switches 72 and 73 are housed and an insulating gas is enclosed, since an insulating gas is used as an extinguishing medium for the load switches 72 and 73, arced gas is generated at the time of opening and closing, and due to this, the withstand voltage is increased. There is a risk of deterioration. In order to prevent the breakdown voltage from decreasing, it is necessary to increase the switch interval, which limits the reduction in size. Further, the load switches 72 and 73 are only provided with load current switching capability, and the number of switching lifespan is considerably smaller than that of the vacuum circuit breaker. Therefore, it is not suitable when high stability is required for the system. Is. Further, the switchgear is constructed by combining various types of parts, which requires a long time for assembly and troublesome parts management.

Therefore, an object of the present invention is to provide a switchgear which is highly reliable and can be downsized and have common parts.

[0007]

According to the present invention, three or more sets of slip-on type bushings for a main circuit and a grounding bushing are arranged at the bottom of a container in which an insulating gas is sealed, and are supported on the top of the bushing for the main circuit. A conductor, a vacuum interrupter, an operating insulating rod, etc. are arranged linearly, and the upper movable electrodes of the vacuum interrupters of the same phase of each set are connected by a ring contact and a connecting conductor, and further, a fixed contact for grounding to the supporting conductor. While the movable blades that come in contact with and separate from this contact are attached to the upper part of the grounding bushing respectively, a cable chamber is provided below the container, and two sets of power cables connected to the loop system and a load are supplied inside the cable chamber. It is characterized in that one or more sets of power cables for pulling in are pulled in.

[0008]

The switch and the grounding mechanism existing in each branch of the T-branch circuit at the power receiving point all have the same structure, so that common parts facilitate management of parts and simplification of assembly work. Moreover, since the switch uses a vacuum interrupter that has a high breaking capability and a large number of switching lifespans, the switching operation is highly reliable and stable power supply is performed. Further, since the arc treatment is performed inside the bulb, generation of decomposed gas and the like is eliminated. That is, the cause of the decrease in breakdown voltage is removed, and the size can be reduced.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in the drawings.

Embodiment 1 of the switchgear according to the present invention is shown in FIGS.
As shown in FIG. 1 and 2 are internal structural views, and FIG. 3 and FIG.
Is an outline drawing, and FIG. 5 is a single line connection diagram. In the figure, 1 is a vacuum interrupter used as a switch on the load side, 2 and 3 are vacuum interrupters used as a switch on the power receiving side, 4 is a container in which an insulating gas is sealed, 5 to 7 are 3 at the bottom of the container 4.
Three sets of main circuit slip-on type bushings arranged in rows and three columns, 8 to 10 are main circuit bushings 5 to 7.
3 sets of grounding bushings that are arranged at regular intervals on the sides of the. Supporting conductors 11 to 13, vacuum interrupters 1 to 3, and an insulating plate 14 on top of the main circuit bushings 5 to 7.
To 16, ring contacts 17 to 19 and insulating rod 2
0 to 22 are linearly arranged, and the upper ends thereof are connected to operating mechanisms 23 to 25 including a tripping spring. The vacuum interrupters 1 to 3 are attached with the fixed electrode side down,
The movable lead on the movable electrode side is connected to the ring contacts 17 to 19
It is slidably contacted with and electrically connected. For the ring contacts 17 to 19 of each set, those of the same phase are connected to the conductors 26 to 28.
Connected by The connecting conductors 26 to 28 serve as branch points of the T branch circuit. Fixed contacts 29 to 31 are attached to the support conductors 11 to 13 on the main circuit bushings 5 to 7, and movable blades 32 to 34 that come into contact with and separate from the fixed contacts are attached to the upper parts of the grounding bushings 8 to 10 so as to be rotatable. The operating mechanisms 35 to 37 are connected to the movable blades 32 to 34. This constitutes a two-position type grounding switch. The opening / closing operation of the grounding switch is manual, and the opening / closing operation of the vacuum interrupters 1 to 3 is electrically operated. An interlock mechanism is provided between both operating mechanisms.

On the other hand, a cable chamber 38 is provided below the container 4, and a pair of power cables 39 for feeding a load and two sets of power cables 40, 41 connected to the loop system are drawn therein. , A current transformer 42 connected to the main circuit bushings 5 to 7 and for protection relay and measurement
Equipped with ~ 44. Further, the operation / control box 50 is arranged on the front surface of the container 4, the operation mechanisms 23 to 25, 35 to 37 are housed, and the protective relays 45 to 47 are equipped.

Next, the operation will be described. During normal times, the vacuum interrupters 2 and 3 on the power receiving side are closed, and power is supplied to the load from the loop system through the vacuum interrupter 1 on the load side. When an accident occurs in the loop system,
The fault current is detected, the fault point is identified, and "open" commands are issued to the vacuum interrupters on both sides of the fault current. At the corresponding power receiving point (T branch circuit), the vacuum interrupter 2 on the power receiving side
One of the 3 operates to cut off the fault current. At this time, the other is kept closed and the load is continuously supplied with electric power. Further, the grounding switch ES on the side of the vacuum interrupter that has been shut off can be turned on, and the fault section of the system is grounded by manual operation. When restored, ground switch ES
The vacuum interrupter 2 or 3 is permitted to be supplied under the condition that the open circuit is opened, and the loop system is restored to the normal state.

A second embodiment is shown in FIG. In the second embodiment, two load circuits are used, and one set is additionally provided.
That is, a slip-on type bushing 51 for the main circuit and a grounding bushing 52 are added to the bottom of the container 4 as in the first embodiment.
The rows are arranged in four columns, two columns on both sides are the power receiving side, and the middle two columns are the load side. A support conductor 53, a vacuum interrupter 54, an insulating plate 55, a ring contact 56, and an insulating rod 57 are linearly arranged on the upper portion of the main circuit bushing 51, and the upper end thereof is connected to an operating mechanism 58 including a tripping spring. ing. A fixed contact 59 is attached to the support conductor 53, a movable blade 60 that comes in contact with and separates from the support conductor 53 is rotatably attached to the upper portion of the grounding bushing 52, and an operating mechanism 61 is connected to the movable blade 60. The ring contact 56 connects the same phase to the connection conductors 26 to 28. The power cable 62 is drawn into the cable chamber 38, and a current transformer 63 is installed.

As described above, even if the load circuit is composed of two circuits, the switch and the grounding mechanism existing in each branch of the branch circuit have the same structure, and an accident can be dealt with swiftly and accurately. Further, the commonality of parts reduces the types of parts, which facilitates assembly and part management.

[0015]

As described above, according to the present invention, since all the switches are vacuum circuit breakers, accidents can be dealt with swiftly and accurately, and stable power supply can be expected. . Further, since the arc treatment is performed in the valve, generation of decomposed gas and the like is eliminated, and the reduction in withstand voltage can be eliminated to reduce the size. Further, since the switch and the grounding mechanism existing in each branch of the T-branch circuit at the power receiving point have the same structure, parts can be made common and the number of types can be reduced, which facilitates parts management. With
Assembling work is also easy.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a switchgear according to the present invention.

FIG. 2 is a sectional view showing a first embodiment of a switchgear according to the present invention.

FIG. 3 is a front view showing a first embodiment of a switchgear according to the present invention.

FIG. 4 is a side view showing a first embodiment of a switchgear according to the present invention.

FIG. 5 is a single line connection diagram showing the first embodiment of the switchgear according to the present invention.

FIG. 6 is a sectional view showing a second embodiment of a switchgear according to the present invention.

FIG. 7 is a side view showing a conventional example of an opening / closing device.

FIG. 8 is a rear view showing a conventional example of an opening / closing device.

FIG. 9 is a sectional view showing a conventional example of an opening / closing device.

FIG. 10 is a single line connection diagram showing a conventional example of a switchgear.

[Explanation of symbols]

 1-3 ... Vacuum interrupter 4 ... Container 5-7 ... Main circuit bushing 8-10 ... Grounding bushing 29-31 ... Fixed contact 32-34 ... Movable blade

Claims (1)

[Claims] 1. A slip-on type bushing for a main circuit and three or more sets of grounding bushings are arranged at the bottom of a container in which an insulating gas is sealed, and a support conductor, a vacuum interrupter, and an operating insulation are provided above the bushing for the main circuit. By arranging rods linearly, the upper electrodes of the vacuum interrupters of the same phase of each set are connected by a ring contact and a connecting conductor, and further, a fixed contact for grounding is provided on the supporting conductor, and an upper contact is provided on the grounding bushing. While installing movable blades that come into contact with and separate from the contacts, respectively, a cable chamber is provided below the container, and two sets of power cables connected to the loop system and one or more sets of power cables for supplying power to the load are provided inside the cable chamber. An opening and closing device characterized in that it is adapted to retract.