KR100848124B1 - A load breaker switchgear - Google Patents

Abstract

A load breaker switchgear is provided to improve arc-suppressing capability by increasing an SF6(Sulphur hexaFluoride) gas storage space inside a cylinder and a discharge unit of a piston. A load breaker switchgear(400) includes a barrier(410), buffers(420), fixing contacts(450,460), a shaft(470), and moving arms(480). The barrier includes a plurality of division parts divided at equal intervals. The buffers are mounted on each of the division parts and suppress an arc by instantaneously discharging a stored SF6 gas. The fixed contacts are detachably mounted to both inclined planes of each of the division parts. The shaft is installed through the division parts. The moving arms are connected to the shaft at one ends and connected to the buffers at the other ends to rotate the buffers through rotation of the shaft.

Description

Load switch {A LOAD BREAKER SWITCHGEAR}

The present invention relates to a load switch, and more particularly, to increase the thickness of the fixed contact point and the movable contact point to withstand a fault current of 25 kA, and to improve the SF6 gas storage space and the discharge portion of the piston inside the cylinder, compared to the conventional art. The present invention relates to a load switchgear that exhibits arc extinguishing ability, and is equipped with buffers in each partition in an integrated barrier, and that a compact configuration is possible, and that a buffer can be easily replaced in the event of a buffer failure.

In the power plant, electricity having a voltage of about 200,000 V is boosted to a very high voltage suitable for power transmission, and is transmitted to the primary substation. In the primary substation, the supplied power drops to 22,900 V to be supplied to the secondary substation and each customer. . At this time, the power supplied from the primary substation is supplied to the power receiving equipment of each customer through a distribution system consisting of overhead distribution line and underground distribution line, and is supplied to the low voltage consumer side through the special high-pressure consumer, high-pressure consumer and various outdoor installation transformer.

In general, the load breaker is an important power device that enters the outdoors or indoors in a power distribution system rated voltage 25.8kV underground water distribution line. In charge.

1 schematically shows a side view of a load switch according to the prior art.

Referring to FIG. 1, each buffer 140, 150, 160 of the load switch 100 is located in a separate barrier 110, 120, 130 corresponding to each buffer 140, 150, 160. The barriers 110, 120, 130 are connected to each other by the shaft 170. Such a structure in which the barriers 110, 120, and 130 exist for each of the buffers 140, 150, and 160 has caused a problem that requires a lot of installation space in installing the load switch 100. In addition, each of the barriers 110, 120, 130 connected to each other by the shaft 170 is fixed to the shaft 170 by an adhesive, one end of which is connected to the buffers 140, 150, 160 and the other end of the shaft. Moving arms 180, 182, and 184 connected to the 170 are also fixed to the shaft 170 by an adhesive, so that even if only one of the three buffers 140, 150, 160 fails, the load breaker 100 There was a problem to replace the whole. As a result, there was a disadvantage in that a high cost and a large work time for replacement were required.

2 (a) and 2 (b) schematically show a perspective view and a bottom view of the buffer of the load switch according to the prior art, respectively.

The buffer 140 of the load switch according to the prior art includes a cylinder 142 and a piston 144. A movable contact 146 is formed on the outer circumferential surface of the piston 144. The load switch according to the prior art uses the SF6 gas filled in the cylinder to buffer arcs generated between the fixed contact point and the movable contact point. However, in the case of the buffer 140 according to the related art, the diameter of the fixed contact (not shown) is about 16 to 20 mm, so that the fault current can withstand only about 12.5 kA. As a result, the fixed contact point and the movable contact point are easily fused at the time of energizing a large current exceeding 12.5 kA due to an accident, and thus the buffer 140 is easily broken. In addition, a vacuum breaker having a rated breaking current of 25 kA has a disadvantage in that it cannot be used together due to an excessive design problem due to performance difference.

In addition, referring to the operation of the buffer 140, when the piston 144 is pushed into the cylinder 142, the SF 6 gas stored in the cylinder 142 is released. However, as shown in FIGS. 2A and 2B, the SF6 gas storage space inside the cylinder 142 is small, so that the discharge amount of the SF6 gas is small and formed on the bottom surface of the buffer 140 ( 148), too, because the SF6 gas inside the cylinder was not released a lot, there was a problem that the arc extinguishing capacity is falling.

The present invention has been made to solve the above problems, the object of the present invention, the thickness of the fixed contact and the movable contact to withstand a fault current of 25kA by 25 to 30 mm, compared with the conventional The SF6 gas storage space and the discharge part of the piston are enlarged to show an improved arc extinguishing ability. The buffers are installed in each compartment of the integrated barrier, allowing for a compact configuration and easy attachment and detachment of the buffer. It is to provide a load breaker that can.

The load switch according to the present invention for achieving the above object, the barrier having a plurality of partitions are partitioned at equal intervals; A buffer mounted in each of the plurality of compartments, for instantaneously releasing the stored SF6 gas to extinguish the arc; A fixed contact detachably mounted to both inclined surfaces of each of the plurality of partitions; A shaft installed to penetrate the plurality of partitions; And a moving arm having one end connected to the shaft and the other end connected to the buffer to rotate the buffer by a rotation operation of the shaft.

The buffer includes a cylinder detachably mounted to each of the plurality of partitions; A movable contact, the portion of which is located inside the cylinder in the longitudinal direction of the cylinder; And a piston reciprocating on the inner circumferential surface of the cylinder during opening and closing of the load switch.

Preferably, the cylinder is connected to each of the plurality of compartments by bolts and nuts.

The width of the movable contact located inside the cylinder is preferably 25 to 30 mm. As the width of the movable contact becomes smaller than 25 mm, it is able to withstand the fault current of less than 25 kA, and when the width of the movable contact becomes larger than 30 mm, the load switch becomes larger.

The piston may include a first tulip contact in contact with the movable contact; A second tulip contact in contact with the stationary contact; And a current-carrying contact whose both ends are fitted into the inner circumferential surface of each of the first and second tulip contacts.

The piston may further include a pressure spring provided on the outer circumferential surface of each of the first and second tulip contacts.

The fixed contact may include a contact portion which contacts the buffer when the load switch is closed; And a connection part protruding to the outside of the barrier for connection with other parts.

In this case, it is preferable that the width of the contact portion is larger than the width of the connection portion, and the width of the contact portion is 25 to 30 mm. As the width of the contact becomes smaller than 25 mm, it is able to withstand the fault current of less than 25 kA, and as the width becomes larger than 30 mm, the load switch is large.

The moving arm is preferably connected to the shaft by bolts and nuts.

As described above, the load switch according to the present invention has the effect of withstanding the fault current from 12.5kA to 25kA by setting the width of the fixed contact and the movable contact to 25 to 30 mm, respectively.

In addition, the SF6 gas storage space in the cylinder is increased to store a large amount of SF6 gas, and the discharge portion of the piston is also formed large, so that a large amount of SF6 gas stored in the cylinder is released at once, showing excellent arc extinguishing ability.

In addition, the cylinder of the buffer is detachably attached to each compartment of the barrier, and the moving arm connected to the piston of the buffer is detachably attached to the shaft, so that the buffer can be replaced for each buffer in case of failure or inspection of the buffer. . Therefore, the cost can be reduced and the working time can be reduced.

In addition, since the buffer is mounted on each partition of the barrier formed integrally, a compact configuration is possible.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the following examples.

Figure 3 schematically shows a side view according to an embodiment of the load switch according to the invention. Figure 4 (a) schematically shows a first front cross-sectional view according to an embodiment of the load switch according to the present invention.

As shown in FIGS. 3 and 4A, the load switch 400 includes a barrier 410 and a barrier 410 having a plurality of partitions 412, 414, and 416 partitioned at equal intervals. Of the buffers 420, 430, 440 and arcuate buffers 420, 430, and 440, which are mounted in each of the compartments 412, 414, and 416, to instantaneously discharge the stored SF6 gas. Fixed contacts 450 and 460 mounted on both inclined surfaces, shafts 470 passing through the partitions 412, 414 and 416, and moving arms for rotating the buffer 420 by the rotation of the shaft 470. 480.

In the case of the load switch according to the prior art, as described above, a separate barrier exists for each buffer and each barrier is connected through a shaft, whereas the load switch according to the present invention has a buffer 420, 430, 440. Barriers 410 having respective partitions 412, 414, 416 partitioned at equal intervals to be mounted are integrally formed, and each partition of the barrier 410 integrally formed with a shaft 470 ( 412, 414, and 416 are installed to penetrate, allowing a compact configuration compared to the load switch according to the prior art.

In this embodiment, a three-phase load switch with three buffers was used, but in an alternative embodiment, a four-phase load switch with four buffers may be used.

The fixed contacts 450 and 460 are contact parts 452 and 462 which contact the buffer 420 when the load breaker is closed, and a connection part 454 protruding out of the barrier 410 for connection with other components. , 464). Connections 454 and 464 of the fixed contacts 450 and 460 are filled with nuts 456 and 466 for fixing. The contact portions 452 and 462 and the connection portions 454 and 464 of the fixed contacts 450 and 460 have a cylindrical shape. The width of the contact portions 452 and 462 of the fixed contacts 450 and 460 is larger than the width of the connection portions 454 and 464, and the width of the contact portions 452 and 462 in this embodiment is 25 mm. The contact portions 452 and 462 of the fixed contact according to the present invention and the movable contact to be described later have an advantage that can withstand a fault current up to 25 kA because the width thereof is larger than that of the conventional fixed contact and the movable contact.

One end of the moving arm 480 is connected to the buffer 420, and the other end is connected to the shaft 470. The connection of the moving arm 480 to the shaft 470 has a fastening structure of a bolt and a nut and is easily removable.

Figure 4 (b) schematically shows a second front cross-sectional view according to an embodiment of the load switch according to the present invention. 5 (a) and 5 (b) schematically show a perspective view of a state in which the cylinder and the piston of the load switch according to the invention is coupled.

4 (b), 5 (a) and 5 (b), the buffer 420 mounted in each compartment of the barrier 410 includes a cylinder 422, a piston 424 and a movable contact 426. ). A circular portion 428 having a diameter equal to the width of the movable contact 426 is drilled at the upper end of the cylinder 422, and the movable contact 426 is fitted into the circular portion 428 to form the cylinder 422. It is located inside the cylinder 422 in the longitudinal direction. The movable contact 426 has a cylindrical shape similar to the fixed contacts 450 and 460, and the width of the movable contact 426 is 25 mm in this embodiment. The contact portions 452 and 462 and the movable contact 426 of the fixed contact according to the present invention has the advantage that can withstand the fault current up to 25kA because the width is larger than the width of the conventional fixed contact and the movable contact.

The movable contact 426 and the cylinder 422 are fastened to the coupling hole 490 in a bolt and nut structure at the upper end of the partition, so that the movable contact 426 and the cylinder 422 are easily detachable. In addition, as described above, the moving arm 480 is also fastened to the shaft 470 by a bolt and nut structure, so that it is easy to attach and detach. Due to the fastening structure of the bolt and nut, it is possible to replace only the buffer 420 without having to replace the entire load switch 400 when the buffer 420 is broken, thereby reducing costs and reducing work time.

The piston 424 reciprocates in the inner circumferential surface of the cylinder 422 during opening and closing of the load switch 400. Both ends of the piston 424 are provided with first and second tulip contacts 491 and 492 inward. The energizing contact 493 is a hollow cylindrical shape whose width at both ends is smaller than the width at the center portion, and both ends are fitted to the inner circumferential surfaces of the first and second tulip contacts 491 and 492, respectively.

Each of the first and second tulip contacts 491 and 492 is in contact with the contact portion 462 of the movable contact 426 and the fixed contact 460, and the energizing contact 493 is connected to the first and second tulip contacts 491, 492) in contact with each other, current flows through the movable contact 426, the first tulip contact 491, the electricity contact 493, the second tulip contact 492, and the fixed contact 460.

6 and 7 schematically show a plan view and a bottom view, respectively, according to an embodiment of the piston of the load switch according to the present invention.

6 and 7, a first tulip contact 491 is mounted on an upper side of the piston 424, and a first press spring 494 and a second pressurization are provided on an outer circumferential surface of the first tulip contact 491. A spring (No. 495 in Fig. 4B) is provided. In addition, a second tulip contact 492 is mounted below the piston 424, and third and fourth pressure springs (No. 496, 497 in FIG. 4 (b) are provided on the outer circumferential surface of the second tulip contact 492). ) Is installed. In this embodiment, two pressure springs are provided on the outer circumferential surface of each of the first and second tulip contacts, but in alternative embodiments, one or three pressure springs may be provided on the outer circumferential surface of each of the first and second tulip contacts. have.

The piston 424 has a discharge portion 498 formed by the first and second tulip contacts 492, which are larger in width than the discharge portion of the buffer of the load switch according to the prior art. Because of this, a large amount of SF6 gas can be released in an instant, showing excellent arc extinguishing capability.

The first and second pressure springs 494 and 495 press the first tulip contact 491 to strengthen the contact between the first tulip contact 491 and the movable contact 426, and the third and fourth pressure springs. 496 and 497 press the second tulip contact 492 to strengthen the contact 462 of the second tulip contact 492 and the fixed contact 460.

Referring to the opening and closing operation of the load switch according to the invention as follows.

Figure 8 schematically shows a state diagram relating to the opening and closing operation of the load switch according to the present invention.

The load switch is normally in a closed state as shown at the leftmost side of FIG. 8, and is opened as shown at the rightmost side of FIG. 8 when an overcurrent flows. Referring to FIG. 8, when overcurrent flows, the shaft 470 of the load switch 400 rotates by an external force, and the moving arm 480 moves the buffer 420 of the barrier 410 by the rotation force of the shaft 470. Move it to the center. During the movement of the buffer 420, the piston 424 is moved to the inner side of the cylinder 422 by the moving arm 480, the SF6 gas stored in the cylinder 422 at the pressure generated when moving to the inner side Arc arc while being released momentarily in a direction opposite to the direction of travel of piston 424. The SF6 gas storage space inside the cylinder 422 is made larger than the SF6 gas storage space inside the cylinder according to the prior art, and the discharge portion 498 at the piston is larger than the discharge portion of the piston according to the prior art, thereby storing it in the cylinder. The arc extinguishing is superior to the conventional load breaker because the large amount of SF6 gas that is used is instantly and strongly released. After arc extinguishing, the shaft 470 rotates by an external force and the moving arm 480 moves the buffer 420 in one of the outward directions from the center of the barrier 410 by the rotational force of the shaft 470. .

While specific embodiments of the present invention have been described above, the present invention is not limited to the above-described specific embodiments, and the technical field to which the present invention pertains without departing from the spirit of the present invention as claimed in the claims. Anyone of ordinary skill in the art can make various modifications, as well as such modifications are within the scope of the claims.

1 schematically shows a side view of a load switch according to the prior art.

2 (a) and 2 (b) schematically show a perspective view and a bottom view of a buffer of a load switch according to the prior art, respectively.

Figure 3 schematically shows a side view according to an embodiment of the load breaker of the present invention.

4 (a) and 4 (b) schematically show a first front cross-sectional view and a second front cross-sectional view, respectively, according to an embodiment of the load switch according to the present invention.

5 (a) and 5 (b) schematically show a perspective view of a state in which the cylinder and the piston of the load switch according to the present invention is coupled.

Figure 6 schematically shows a plan view according to an embodiment of the piston of the load switch according to the invention.

Figure 7 schematically shows a bottom view according to an embodiment of the piston of the load switch according to the invention.

Figure 8 schematically shows a state diagram relating to the opening and closing operation of the load switch according to the present invention.

Claims (9)

A barrier having a plurality of partitions partitioned at equal intervals; A buffer mounted to each of the plurality of compartments, for instantaneously releasing the stored SF6 gas to extinguish the arc; A fixed contact detachably mounted to both inclined surfaces of the plurality of partitions; A shaft installed to penetrate the plurality of partitions; And And a moving arm having one end connected to the shaft and the other end connected to the buffer to rotate the buffer by a rotation operation of the shaft. The method of claim 1, wherein the buffer, A cylinder detachably mounted to each of the plurality of compartments; A movable contact, a portion of which is located inside the cylinder in the longitudinal direction of the cylinder; And And a piston reciprocating on the inner circumferential surface of the cylinder when opening and closing the load switch. The load switch of claim 2, wherein the cylinder is connected to each of the plurality of partitions by a bolt and a nut. 3. The load switch as claimed in claim 2, wherein a width of the movable contact positioned inside the cylinder is 25 to 30 mm. The method of claim 2, wherein the piston, A first tulip contact in contact with said movable contact; A second tulip contact in contact with said stationary contact; And And a current-carrying contact whose both ends are fitted into the inner circumferential surface of each of the first and second tulip contacts. The method of claim 5, wherein the piston, And a pressure spring provided on an outer circumferential surface of each of the first and second tulip contacts. The method of claim 1, wherein the fixed contact, A contact portion which contacts the buffer when the load switch is closed; And And a connecting portion protruding to the outside of the barrier for connection with other components. The load switch of claim 7, wherein the width of the contact portion is greater than the width of the connection portion, and the width of the contact portion is 25 to 30 mm. The load switch of claim 1, wherein the moving arm is connected to the shaft by a bolt and a nut.

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