JP2008113516A - Main circuit switchgear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate the maintenance by securing the maintenance space for various electric goods, even though the main circuit switchgear of a power plant is reduced in size more and more, in recent years. <P>SOLUTION: This main circuit switchgear has such a constitution that first and second mobile trucks which mount first and second high-voltage apparatuses, respectively, to which bushings leading to a breaker and a disconnector are connected via detachable contacts, can be moved and arranged outside a frame separated in reverse direction from each other in the axial direction of a bus on rails, under the breaker and disconnector within the frame which support the breaker and the disconnector, whereby the user can maintain the first and second high-voltage apparatuses that are the maintenance-target apparatuses and are maintained easily and safely outside the frame. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an improvement of a main circuit switchgear, and in particular, a main circuit of a generator installed between a main generator and a main transformer in a low-voltage synchronous system of a power plant such as nuclear power, thermal power, and hydropower. The present invention relates to a switchgear.

For the start-up of generators in power plants, the use of a low-voltage synchronous system is actively used instead of a high-voltage synchronous system.
In this low-voltage synchronous system, the main circuit switchgear is arranged on the input side of the main transformer. In this main circuit switchgear, the main circuit breaker and the main circuit disconnector are integrated and housed in a metal container, The above-mentioned metal container is placed on the instrument, and the instrument transformer is installed directly under the circuit breaker of the gantry, and the instrument transformer, surge absorbing capacitor and surge arrester are housed immediately below the disconnector. A device that reduces the cost and reduces the installation area is disclosed (for example, Patent Document 1).

JP 2002-186126 A

  In order to supply stable power, maintenance of instrument transformers, surge absorbing capacitors, and lightning arresters is regularly performed in power plants. This maintenance includes operations such as cleaning of each part, performance check, deterioration diagnosis, and part replacement. Even under recent circumstances, it is required to perform the maintenance more reliably in a shorter period of time. In addition, when an abnormality occurs, there is a need to safely replace parts without stopping the generator.

  However, maintenance of the instrument transformer, surge absorbing capacitor and lightning arrester arranged in the main circuit breaker frame shown in Patent Document 1 must be carried out by workers entering the frame, Since it is a miniaturized device with a small installation area, there are problems such as a narrow working space and difficult access.

  The present invention solves the above-described problems, and makes it possible to safely and easily perform maintenance of high-voltage devices arranged in a gantry even when the main circuit is in a live line state. An object of the present invention is to provide a circuit switching device.

  A main circuit switchgear according to the present invention includes a circuit breaker and a container for accommodating a disconnector, which are installed in series in an axial direction, and a gantry for supporting the container. The first mobile carriage on which one high-voltage device is mounted is provided, and the circuit breaker and the first high-voltage device are connected via a detachable first contact. Inside the lower pedestal is a second mobile carriage for mounting the second high-voltage device, and the disconnector and the second high-voltage device are connected via a detachable second contact. The first and second movable carriages are connected to each other and are installed on a rail, and the circuit breaker and the first carriage are moved on the rail independently or both in the axial direction. The connection through the first contact with the high-voltage device is Alternatively, the connection between the disconnector and the second high-voltage device via the second contact is released individually or both, and the first and second movable carriages can be moved to the outside of the gantry. is there.

  A main circuit switchgear according to the present invention includes a circuit breaker and a container for accommodating a disconnector, which are installed in series in an axial direction, and a gantry for supporting the container. The first mobile carriage on which one high-voltage device is mounted is provided, and the circuit breaker and the first high-voltage device are connected via a detachable first contact. Inside the lower pedestal is a second mobile carriage for mounting the second high-voltage device, and the disconnector and the second high-voltage device are connected via a detachable second contact. The first and second movable carriages are connected to each other and are installed on a rail, and the circuit breaker and the first carriage are moved on the rail independently or both in the axial direction. The connection through the first contact with the high-voltage device is Alternatively, the connection between the disconnector and the second high-voltage device via the second contact is released individually or both, and the first and second movable carriages can be moved to the outside of the gantry. Therefore, the first and second high-voltage devices mounted on the first and second movable carriages can be easily maintained, and the main circuit is attached to the main circuit switching device even when the main circuit is in a live state. Maintenance of the first and second high-voltage devices is possible, and as a result, maintenance can be performed without shutting down the power plant. Furthermore, since maintenance can be performed outside the gantry, there is an excellent effect that the safety of work by workers is improved and more reliable maintenance can be performed.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings.
FIG. 1 is a front view of a power generation main circuit switching device 100 according to the first embodiment. FIG. 2 is a single line connection diagram thereof. 1 and 2, main circuit switching device 100 includes main circuit breaker 1 and main circuit disconnector 2 connected in series in the axial direction of bus 60, and the circuit breaker-side grounding device shown in FIG. 3a, disconnector side grounding device 3b, instrument current transformer (CT) 4, circuit breaker side instrument transformer 5a installed for the purpose of voltage measurement and abnormal voltage protection of the main circuit, and for disconnector side instrument It comprises a transformer 5b, a surge absorbing capacitor 6 for protecting abnormal voltage, a lightning arrester 7, and the like.
In the first embodiment, the instrument transformer (PT) 5a on the circuit breaker 1 side is used as the first high voltage device 50a, and the instrument transformer (PT) 5b on the disconnector 2 side is used for surge absorption. A general term for the capacitor and the lightning arrester 7 is referred to as a second high-voltage device 50b. The first and second high-voltage devices 50a and 50b are not limited to the devices described above, and may include other devices for measurement, protection, and the like.

  Referring to FIG. 1, main circuit breaker 1 and main circuit disconnector 2 are connected in series in the axial direction of bus bar 60 and are housed in metal container 9. It is installed. Inside the gantry 10 below the main circuit breaker 1, a circuit breaker-side instrument transformer 5a corresponding to the first high-voltage device 50a is connected to the first movable carriage 12a via a breaker-side bushing 11a. It is installed. In the lower part of the main circuit disconnector 2, a disconnector-side instrument transformer 5b, a surge absorbing capacitor 6, and a lightning arrester 7 corresponding to the second high-voltage device 50b are connected via a disconnector-side bushing 11b. It is mounted on the second movable carriage 12b. The first and second movable carriages 12a and 12b are configured to be movable on the rail 13 in the axial direction, that is, in the left-right direction in FIG. The breaker-side bushing 11a and the first high-voltage device 50a connected to the breaker 1 or the disconnector-side bushing 11b and the second high-voltage device 50b connected to the disconnector 2 are respectively the first and second movable carriages 12a, 12b are connected via detachable first and second contacts 14a and 14b that enable the movement of each of them individually or both. In FIG. 1, the first and second contacts 14a and 14b are the bushings 11a and 11b in the female side, the first and second high-voltage devices 50a and 50b are in the male side, and the male side is supported by the support body 17. Although the example to do is shown, arrangement | positioning with the said male and female reverse may be sufficient.

  A first positioning device 15a for positioning both the rail 13 and the first movable carriage 12a at a predetermined position so that the male and female of the first and second contacts 14a and 14b are in close contact with each other. A second positioning device 15b is provided on the second movable carriage 12b side. The first and second positioning devices 15a and 15b may be mechanical stoppers that can stop the first and second movable carriages 12a and 12b on the rails 13 at predetermined axial positions, respectively. A non-contact type position detection device that measures the distance between the movable carriages 12a and 12b and the gantry 10 electrically or optically may be used. In this case, if a guide mechanism is provided in the vicinity of the stopper so as to place each of the first and second movable carriages 12a and 12b at a predetermined position in the direction perpendicular to the axis, more accurate positioning can be achieved. The first and second movable carriages 12a and 12b in the gantry 10 move in the axial direction (left-right direction) in FIG. A protective cover 16 is provided around the frame 10, and doors 16 a are provided at both ends in the axial direction of FIG. 1 as shown in FIG. 3.

FIG. 3 is a plan view of the gantry 10 including the first and second high-voltage devices 50a and 50b in the main circuit switchgear 100 as viewed from above, and shows a three-phase busbar. The first and second movable carriages 12a and 12b move in opposite directions in the bus axis direction (corresponding to the vertical direction in FIG. 3), and the first and second high-voltage devices 50a and 50b are located outside the gantry 10. The state moved to is shown.
When the first and second movable carriages 12a and 12b in the state of FIG. 1 described above open the doors 16a at both ends in the axial direction of the gantry 10, the opposite directions, that is, the gantry 10 are linked to the opening of the door 16a. 3 to the state shown in FIG. The door 16a is provided with a lever 16b and a link 16c. One end of the link 16c is fixed to the first and second movable carriages 12a and 12b, and the first and second movable carriages 12a and 12b are pulled out. Making it easy.

Thus, the first and second high-voltage devices 50a and 50b mounted on the movable carriages 12a and 12b are moved by the movement of the first and second movable carriages 12a and 12b. Since the male and female of 14b are detached and separated from the main circuit (bus), the first and second high voltage devices 50a and 50b are configured to be movable and arranged outside the gantry 10. The maintenance work such as cleaning, performance confirmation, deterioration diagnosis, parts replacement, etc., becomes easy.
Furthermore, since the first and second high-voltage devices 50a and 50b move to the outside of the gantry 10, the workability of maintenance workers can be improved and safety can be ensured even when the main circuit is in a live state. At the same time, maintenance time can be further shortened.

  After the maintenance is completed, by closing the door 16a, the first and second movable carriages 12a and 12b are moved into the frame 10 on the rail 13, and the first and second positioning devices 15a and 15b The position, that is, the position where the male and female of the first and second contacts 14a and 14b are in close contact with each other stops and returns to the state shown in FIG.

  In the first embodiment, the first and second movable carriages 12a and 12b move independently or both in conjunction with the opening and closing of the door 16a, but not in conjunction with the opening and closing of the door. The configuration may be such that after the door is simply opened, the movable carriage is moved either manually or synchronously by other driving sources.

Embodiment 2. FIG.
FIG. 4 shows a main circuit switching device 100 according to the second embodiment.
In the second embodiment, a partition plate 19 of a metal plate or an insulating plate is provided on the first and second movable carriages 12a and 12b, and the first and second contacts are provided on the partition plate 19 via an insulator 18. 14a and 14b are provided. The partition plate 19 is installed so as to hide the breaker-side bushing 11a and the disconnector-side bushing 11b, which are high-voltage application portions of the main circuit, when viewed from the outside of the gantry 10 in the axial direction. By providing the partition plate 19 in this way, when the main circuit is in the live line state, even if the first or second high voltage device 50a, 50b needs to be inspected for some reason, the inspection worker Can be inspected without contacting the bushing 11a or the bushing 11b.

  Embodiments 1 and 2 of the present invention can be used for a generator main circuit switching device of a low-voltage synchronous system of a power plant.

It is a front view of the main circuit switching device by Embodiment 1 of this invention. It is a single wire connection diagram of the main circuit switchgear according to Embodiment 1 of the present invention. It is the top view seen from the mount upper part of the main circuit switchgear by Embodiment 1 of this invention. It is a front view of the main circuit switchgear by Embodiment 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Circuit breaker, 2 disconnector, 9 container, 10 mounts, 12a 1st moving trolley,
12b Second moving carriage, 13 rail, 14a First contact,
14b second contact, 15a first positioning device,
15b second positioning device, 16a door, 50a first high voltage device,
50b Second high voltage device, 100 main circuit switchgear.

Claims (4)

A main circuit switching device, comprising: a breaker installed in series in the axial direction; a container for housing the disconnector; and a gantry for supporting the container; A first mobile carriage equipped with one high-voltage device is provided, and the circuit breaker and the first high-voltage device are connected via a detachable first contact, A second mobile carriage carrying a second high-voltage device is provided in the gantry below the disconnector, and the disconnector and the second high-voltage device are detachable. The first and second movable carriages are installed on a rail and moved on the rail independently in the axial direction or by moving both of them apart from each other. The circuit breaker and the first high voltage device; The connection through the first contact or the connection between the disconnector and the second high-voltage device through the second contact is released individually or both, and the first and second A main circuit switchgear characterized in that a movable carriage is movable to the outside of the gantry. 2. The main circuit switching device according to claim 1, wherein the first and second movable carriages move to the outside of the gantry in synchronization with opening of a door provided on the gantry. Positioning devices are provided at predetermined positions of the first and second movable carriages and the rails, and the first and second movable carriages are positioned by the positioning device, so that the first and second movable carriages are positioned. 3. The main circuit switching device according to claim 2, wherein the connection through the second contact can be performed densely. The main circuit switching device according to claim 3, wherein the positioning device is an electrical or optical position reading device that is provided between the movable carriage and a pedestal and transmits and receives a distance signal.

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