Composite self-blasting gas circuit breaker

Abstract

A composite self-blasting gas circuit breaker according to the present invention comprises: a fixed arcing contact; a cylinder having a thermal expansion chamber; a movable arcing contact of which at least a portion is disposed inside the cylinder and into which the fixed arcing contact is partially inserted; and a main nozzle coupled to the cylinder, wherein a portion of the main nozzle is positioned inside the thermal expansion chamber, and a communication hole communicating with the thermal expansion chamber can be provided in the portion of the main nozzle positioned inside the thermal expansion chamber.

Description

Composite gas circuit breaker

[0001] The present invention relates to a composite gas circuit breaker.

[0002] Generally, gas-insulated circuit breakers are installed on transmission lines to perform opening and closing operations for equipment and line inspection when the transmission line is in normal condition, and to safely protect the line and load equipment by blocking fault current when the transmission line is in abnormal condition.

[0003] In particular, in ultra-high voltage power systems, it is a device that safely blocks fault currents in abnormal conditions such as ground faults and short circuits to protect the system. In other words, in abnormal conditions, which are harsh current blocking conditions, an arc-extinguishing gas with excellent insulating properties is compressed to block the fault current and injected through a nozzle at high pressure to extinguish the arc generated when the current is blocked.

[0004] The composite arc-type gas circuit breaker uses the heat generated by the arc when interrupting a fault current as energy to increase the pressure in the thermal expansion chamber. When the current reaches zero, the high-pressure gas from the thermal expansion chamber is injected back into the gap between the electrodes (the arcing section) to maintain insulation between the electrodes, thereby interrupting the gap between the electrodes. This composite arc-type gas circuit breaker generates high-temperature thermal gas due to the arc generated between the electrodes when interrupting.

[0005] In order to improve the interrupting performance of a composite gas circuit breaker, it is necessary to design it so that high pressure, low temperature gas is ejected from the thermal expansion chamber to the area where the arc occurs at the time of the interrupting current zero.

[0006] The purpose of the present invention is to provide a composite arc-type gas circuit breaker capable of improving the blocking performance by providing one or more holes in the main nozzle to facilitate the flow inside the thermal expansion chamber and increase the flow rate of insulating gas discharged to the arc area at the time of current zero.

[0007] A composite arc-type gas circuit breaker according to one embodiment of the present invention comprises: a fixed arc contact; a cylinder having a thermal expansion chamber; a movable arc contact having at least a portion disposed inside the cylinder and arranged such that the fixed arc contact is partially inserted; and a main nozzle coupled to the cylinder, wherein the main nozzle is provided such that a portion thereof is positioned inside the thermal expansion chamber, and a communication hole communicating with the thermal expansion chamber may be provided at a portion of the main nozzle located inside the thermal expansion chamber.

[0008] In one embodiment, the main nozzle includes a first portion positioned outside the cylinder, and a second portion extending from the first portion into the thermal expansion chamber, and the communication hole may be formed in at least a portion of the second portion.

[0009] In one embodiment, the communication hole may be formed on one side of the first portion relative to a center line that bisects the length of the second portion.

[0010] In one embodiment, the main nozzle is coupled to the front end of the cylinder, and the communication hole may be formed such that at least a portion thereof is connected to the inner wall of the front end of the cylinder forming the thermal expansion chamber.

[0011] In one embodiment, a first inner surface adjacent to the first portion among the facing inner surfaces of the communication hole may be connected to the inner wall.

[0012] In one embodiment, the communication hole may be formed such that the first inner surface is positioned on the same line as the inner wall.

[0013] In one embodiment, the communication hole may include a first communication hole and a second communication hole arranged along the longitudinal direction of the main nozzle.

[0014] In one embodiment, the first communication hole and the second communication hole may be formed on one side of the first portion relative to a center line that bisects the length of the second portion.

[0015] In one embodiment, the second communication hole may be formed at a position spaced apart from the center line in the one direction by a predetermined distance, and the first communication hole may be formed at a position spaced apart from the second communication hole in the one direction by a predetermined distance.

[0016] In one embodiment, the composite arc-type gas circuit breaker further includes an auxiliary nozzle disposed inside the main nozzle so as to partially surround the movable arc contact, and a flow path for gas to flow may be formed between the main nozzle and the auxiliary nozzle.

[0017] In one embodiment, the communication hole may connect a portion of the space surrounding the outer surface of the second portion of the thermal expansion chamber and a portion of the flow path in a direction perpendicular to the longitudinal direction of the main nozzle.

[0018] In one embodiment, the communication hole may include two or more long holes spaced apart from each other along the circumferential direction on the outer surface of the main nozzle.

[0019] In one embodiment, the communication hole may be formed in a shape in which the width or cross-sectional area becomes narrower from the outer surface to the inner surface of the main nozzle.

[0020] In one embodiment, the communication hole may be formed in a shape that is inclined in the direction in which the main nozzle protrudes from the cylinder as it moves from the outer surface of the main nozzle to the inner surface.

[0021] A composite arc-type gas circuit breaker according to an embodiment of the present invention can improve the flow of hot gas flowing into the thermal expansion chamber and cold gas existing in the thermal expansion chamber by forming one or more rows of communication holes that extend into the interior of the thermal expansion chamber, thereby increasing the pressure of the thermal expansion chamber, and can increase the pressure and lower the temperature of gas discharged to the arc area at the time of current zero, thereby improving the interruption performance.

[0022] FIG. 1 is a cross-sectional view of a composite gas circuit breaker according to a first embodiment of the present invention.

[0023] Fig. 2 is a perspective view of the main nozzle of a composite small-bore gas circuit breaker according to the first embodiment of the present invention.

[0024] Fig. 3 is a cross-sectional view of the main nozzle of a composite small-bore gas circuit breaker according to the first embodiment of the present invention.

[0025] FIG. 4a and FIG. 4b are drawings illustrating a blocking operation of a composite gas circuit breaker according to a first embodiment of the present invention.

[0026] Fig. 5 is a cross-sectional view of a composite gas circuit breaker according to a second embodiment of the present invention.

[0027] Fig. 6 is a perspective view of the main nozzle of a composite small-capacity gas circuit breaker according to the second embodiment of the present invention.

[0028] Fig. 7 is a cross-sectional view of the main nozzle of a composite small-bore gas circuit breaker according to the second embodiment of the present invention.

[0029] FIG. 8a and FIG. 8b are drawings illustrating a blocking operation of a composite gas circuit breaker according to a second embodiment of the present invention.

[0030] FIGS. 9a, 9b, 9c and 9d are drawings showing various modified examples of the communication hole of the composite small-capacity gas circuit breaker according to the second embodiment of the present invention.

[0031] FIG. 10 is a graph showing a thermal expansion chamber pressure that can predict the blocking performance of a composite arc-type gas circuit breaker according to the first embodiment of the present invention and a composite arc-type gas circuit breaker according to the second embodiment.

[0032] The present invention is susceptible to various modifications and embodiments. Specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the present invention to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention.

[0033] While terms such as "first" and "second" may be used to describe various components, these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component." The term "and / or" encompasses any combination of multiple related items described herein or any one of multiple related items described herein.

[0034] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprise" or "have" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0035] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0036] Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in more detail.

[0037]

[0038] Fig. 1 is a cross-sectional view of a composite arc-type gas circuit breaker (100) according to a first embodiment of the present invention. Fig. 2 is a perspective view of a main nozzle (150) of a composite arc-type gas circuit breaker (100) according to a first embodiment of the present invention. Fig. 3 is a cross-sectional view of a main nozzle (150) of a composite arc-type gas circuit breaker (100) according to a first embodiment of the present invention.

[0039] Fig. 1 illustrates a composite arc-type gas circuit breaker (100) according to a first embodiment in a state of normal current of a gas-insulated switchgear. Fig. 2 illustrates a main nozzle (150) of the composite arc-type gas circuit breaker (100) according to the first embodiment illustrated in Fig. 1, and Fig. 3 illustrates a cross-section II' of the main nozzle (150) illustrated in Fig. 2.

[0040] Referring to FIGS. 1 to 3, a composite arc-type gas circuit breaker (100) according to the first embodiment of the present invention may include a fixed arc contact (110) and a movable part (120).

[0041] The fixed arc contact (110) constitutes a part of a fixed part (not shown) of a composite arc-type gas circuit breaker (100), and at least a part of it can be inserted into a movable part (120). Although not shown, the fixed part of the composite arc-type gas circuit breaker (100) may further include a fixed part support having a fixed arc contact (110) provided at the center thereof.

[0042] The fixed arc contact (110) can extend from a part of the fixed part toward the movable part (120). The fixed arc contact (110) can be inserted into and brought into contact with the movable arc contact (130) of the movable part (120). The fixed arc contact (110) can pass through the main nozzle (150) and the auxiliary nozzle (160) and be fitted into the movable arc contact (130). For example, the fixed arc contact (110) can be inserted into and fitted into the movable arc contact (130) while being accommodated inside the main nozzle (150) and the auxiliary nozzle (160). The fixed arc contact (110) can be electrically contacted and connected with the movable arc contact (130) by being fitted into the movable arc contact (130) at least partially.

[0043] The movable part (120) can be connected to a fixed part including a fixed arc contact (110). The movable part (120) can include a movable arc contact (130), a cylinder (140), and a nozzle (150, 160).

[0044] The movable arc contact (130) may be provided inside the cylinder (140). The movable arc contact (130) may be arranged to penetrate at least a portion of the cylinder (140) and may be surrounded by nozzles (150, 160). For example, the movable arc contact (130) may extend to penetrate the compression chamber (142) and the thermal expansion chamber (141) of the cylinder (140). The movable arc contact (130) may be brought into contact with the fixed arc contact (110) through the nozzles (150, 160). For example, at least a portion of the movable arc contact (130) and the fixed arc contact (110) may be surrounded by the main nozzle (150) and the auxiliary nozzle (160).

[0045] The cylinder (140) may be provided with a thermal expansion chamber (141) and a compression chamber (142) therein. For example, the thermal expansion chamber (141) and the compression chamber (142) may be formed inside the cylinder (140). The thermal expansion chamber (141) and the compression chamber (142) may be arranged side by side along the longitudinal direction of the movable arc contact (130). For example, if the direction in which the nozzles (150, 160) protrude in the composite arc-type gas circuit breaker (100) is defined as forward, the thermal expansion chamber (141) may be positioned forward inside the cylinder (140), and the compression chamber (142) may be positioned rearward of the thermal expansion chamber (141).

[0046] The thermal expansion chamber (141) and the compression chamber (142) may surround the movable arc contact (130). For example, the movable arc contact (130) may be partially positioned inside each of the thermal expansion chamber (141) and the compression chamber (142). The thermal expansion chamber (141) and the compression chamber (142) may be in communication with each other. Although not shown, the thermal expansion chamber (141) and the compression chamber (142) may be in communication with each other through a check valve formed in a partition (145) that divides and separates them.

[0047] The thermal expansion chamber (141) and the compression chamber (142) can form a space in which gas can be accommodated. The compression chamber (142) can have a piston (144) therein. The thermal expansion chamber (141) can be formed as a predetermined space surrounded by a partition wall (145) and an inner wall of a cylinder (140). The compression chamber (142) can be formed as a predetermined space formed by the partition wall (145), the inner wall of the cylinder (140), and the piston (144). The piston (144) can reciprocate in a direction toward the thermal expansion chamber (141) (e.g., forward) and in an opposite direction (e.g., rearward) within the compression chamber (142).

[0048] The thermal expansion chamber (141) can accommodate at least a portion of the nozzle (150, 160) therein. The thermal expansion chamber (141) can be communicated with the flow paths of the nozzles (150, 160). For example, the thermal expansion chamber (141) can be communicated with the flow path (P) between the main nozzle (150) and the auxiliary nozzle (160) and the flow path between the auxiliary nozzle (160) and the arc contacts (110, 130). The internal volume of the compression chamber (142) can change according to the reciprocating motion of the piston (144). For example, the internal volume can decrease as the piston (144) moves toward the thermal expansion chamber (141) (i.e., forward), and the internal volume can increase as the piston (144) moves away from the thermal expansion chamber (141) (i.e., rearward).

[0049] The nozzle (150, 160) may be coupled to the cylinder (140) and may provide a path for the insulating gas contained within the thermal expansion chamber (141) to move and be sprayed between the movable arc contact (130) and the fixed arc contact (110) (e.g., the area where the arc is generated). For example, the nozzle (150, 160) may be coupled to the cylinder (140) such that at least a portion of the nozzle is disposed in the thermal expansion chamber (141). The nozzle (150, 160) may partially surround the movable arc contact (130) and the fixed arc contact (110).

[0050] The nozzles (150, 160) may include a main nozzle (150) coupled to the front end of the cylinder (140) and an auxiliary nozzle (160) disposed inside the main nozzle (150). For example, the main nozzle (150) may be an external nozzle, and the auxiliary nozzle (160) may be an internal nozzle. The main nozzle (150) may be formed in a cylindrical shape surrounding the periphery of the auxiliary nozzle (160) so as to have a predetermined gap with the auxiliary nozzle (160). The auxiliary nozzle (160) may be formed in a cylindrical shape surrounding the periphery of a portion of the movable arc contact (130).

[0051] The main nozzle (150) and the auxiliary nozzle (160) can form or provide a flow path (P) through which gas can flow through a gap formed between the inner surface of the main nozzle (150) and the outer surface of the auxiliary nozzle (160). The main nozzle (150) and the auxiliary nozzle (160) can be provided so that the flow path (P) communicates with the internal space of the thermal expansion chamber (141) and the space between the nozzles (150, 160) and the fixed arc contact (110). For example, the main nozzle (150) and the auxiliary nozzle (160) can be configured so that the discharge end of the flow path (P) faces the fixed arc contact (110) and the inlet end communicates (or is connected) with the thermal expansion chamber (141).

[0052] The auxiliary nozzle (160) extends into the thermal expansion chamber (141) and at least a portion thereof may protrude from the front end of the cylinder (140). The auxiliary nozzle (160) may be connected to the movable arc contact (130) by surrounding the outer surface of the movable arc contact (130) located inside the thermal expansion chamber (141). Fig. 1 schematically illustrates a cross-section of a gas circuit breaker (100), and the auxiliary nozzle (160) may be connected by contacting the movable arc contact (130) at a position where at least a portion thereof is adjacent to the bulkhead (145). In a state of normal current, the auxiliary nozzle (160) may partially surround the outer surface of the fixed arc contact (110).

[0053] The main nozzle (150) is coupled to the front end of the cylinder (140), and at least a portion thereof may protrude from the front end of the cylinder (140). For example, the main nozzle (150) may be inserted into and coupled to an opening formed in the front end of the cylinder (140). The main nozzle (150) may be formed in a cylindrical shape having a hollow portion therein. The main nozzle (150) may be coupled to the cylinder (140) in such a manner that a portion thereof protrudes from the cylinder (140) and the other portion thereof is positioned within the thermal expansion chamber (141).

[0054] The main nozzle (150) may include a first part (151) (or outer part) positioned outside the cylinder (140) when coupled to the cylinder (140) and a second part (152) (or inner part) extending from the first part (151) to be positioned inside the thermal expansion chamber (141). For example, the first part (151) and the second part (152) of the main nozzle (150) may not mean physically distinct or separate parts, but may be understood to define parts positioned outside and inside the cylinder (140) based on the front end of the cylinder (140), respectively. According to various embodiments, the first part (151) may be referred to as a base part, and the second part (152) may be referred to as a guide part.

[0055] Specifically, the second part (152) of the main nozzle (150) may refer to a part that is located inside the thermal expansion chamber (141) when the main nozzle (150) is coupled to the cylinder (140) and is located rearward based on the inner wall (143) of the front end of the cylinder (140), and the first part (151) of the main nozzle (150) may refer to a part of the entire main nozzle (150) excluding the second part (152), which is located outside the cylinder (140) and is located forward based on the inner wall (143) of the front end of the cylinder (140).

[0056] The main nozzle (150) may have a communication hole (154) formed in at least a portion of the second portion (152). The communication hole (154) may be formed along the outer circumferential surface of the main nozzle (150), and at least two communication holes (154) may be formed. The two or more communication holes (154) may be formed to be spaced apart from each other along the circumferential direction of the second portion (152) of the main nozzle (150). The communication hole (154) may be formed to vertically penetrate the outer surface and the inner surface of the second portion (152) of the main nozzle (150).

[0057] According to the illustrated embodiment, the communication holes (154) may be provided in four numbers and may be formed at equal intervals along the circumference of the second part (152) of the main nozzle (150). However, the illustrated embodiment is exemplary, and the shape, number, and / or arrangement of the communication holes (154) are not limited to those illustrated. The communication holes (154) may be formed in two or more numbers, but may be designed in an appropriate number in consideration of the durability and structural stability of the main nozzle (150).

[0058] The communication hole (154) can be communicated with the thermal expansion chamber (141). In addition, the communication hole (154) can be communicated with the flow path (P) of the nozzle (150, 160). The communication hole (154) can communicate and connect the internal space of the thermal expansion chamber (141) and the flow path (P) of the nozzle (150, 160). For example, the communication hole (154) can communicate a part of the internal space of the thermal expansion chamber (141) adjacent to the second part (152) of the main nozzle (150) and the front end of the cylinder (140) with the flow path (P) between the main nozzle (150) and the auxiliary nozzle (160). The flow of gas can be possible between the thermal expansion chamber (141) and the flow path (P) through the communication hole (154).

[0059] The communication hole (154) can communicate and connect the flow path (P) of the nozzle (150, 160) with the internal space of the thermal expansion chamber (141) located on the outer surface of the second part (152) in a direction perpendicular to the central axis (C) of the nozzle (150, 160). For example, the gas inside the thermal expansion chamber (141) can move in a direction perpendicular to the central axis (C) through the communication hole (154) and flow into the flow path (P), and the gas inside the flow path (P) can move in a direction perpendicular to the central axis (C) through the communication hole (154) and flow into the inside of the thermal expansion chamber (141).

[0060] The communication hole (154) may be formed at a position adjacent to the inner wall (143) of the thermal expansion chamber (141). The communication hole (154) may be formed adjacent to the inner wall (143) of the thermal expansion chamber (141) based on the center line (L) of the second part (152). Here, the center line (L) of the second part (152) may be defined as a line that bisects the length of the second part (152) as a vertical bisector of the second part (152). For example, the center line (L) of the second part (152) may pass through the middle of the length direction of the second part (152) by bisecting the second part (152) in a direction perpendicular to the length direction (e.g., the direction of the central axis (C)).

[0061] As illustrated in Fig. 1, the communication hole (154) may be provided to be positioned to the right with respect to the center line (L) of the second portion (152). Here, the right side refers to a direction toward the first portion (151), that is, the communication hole (154) may be formed at a position spaced apart from the center line (L) of the second portion (152) by a predetermined distance in the direction toward the first portion (151). Accordingly, the distance between the communication hole (154) and the inner wall (143) may be shorter than half the length of the second portion (152).

[0062] The communication hole (154) may be provided so that at least a portion thereof is connected to the inner wall (143) of the thermal expansion chamber (141). The communication hole (154) may be partially connected to the inner wall (143) of the front end of the cylinder (140) forming the thermal expansion chamber (141). For example, the communication hole (154) may be formed at a position that can be connected to the inner wall (143) of the second portion (152) of the main nozzle (150).

[0063] The communication hole (154) may have a first inner surface (154a) and a second inner surface (154b) that face each other in the longitudinal direction of the main nozzle (150) (i.e., in the direction parallel to the central axis (C)), and the first inner surface (154a) may be positioned adjacent to the first part (151) and the second inner surface (154b) may be positioned to face the first inner surface (154a). According to the illustrated embodiment, the communication hole (154) may be configured such that the first inner surface (154a) is positioned on the same surface or in the same line as the inner wall (143) of the thermal expansion chamber (141). For example, the first inner surface (154a) of the communication hole (154) may be connected to the inner wall (143) of the front end of the cylinder (140) while forming the same surface. When looking at the longitudinal cross-sectional view of the composite small-capacity gas circuit breaker (100) as shown in Fig. 1, the first inner surface (154a) of the communication hole (154) and the inner wall (143) of the cylinder (140) can be positioned on an imaginary line perpendicular to the central axis (C).

[0064] Meanwhile, the illustrated embodiment is exemplary, and is not limited to being connected while the first inner surface (154a) of the communication hole (154) is positioned on the same surface or the same line as the inner wall (143) of the cylinder (140). According to various embodiments, the first inner surface (154a) of the communication hole (154) may be connected to the inner wall (143) of the cylinder (140) with a step (e.g., see FIGS. 9a and 9b). For example, the communication hole (154) may be formed so that the first inner surface (154a) is spaced apart from the inner wall (143) of the cylinder (140) by a predetermined distance in the direction of the thermal expansion chamber (141). In addition, as another example, the communication hole (154) may be formed so that the inner wall (143) of the cylinder (140) is positioned between the first inner surface (154a) and the second inner surface (154b).

[0065] A composite small-diameter gas circuit breaker (100) according to the first embodiment has a second part (152) in which a main nozzle (150) is positioned inside a thermal expansion chamber (141), and two or more communication holes (154) are formed in the second part (152) along a circumferential direction, so that a smooth flow of gas (hot gas and / or cold gas) can be performed between the flow path (P) of the nozzle (150, 160) and the thermal expansion chamber (141).

[0066]

[0067] FIG. 4a and FIG. 4b are drawings illustrating the blocking operation of a composite gas circuit breaker (100) according to the first embodiment of the present invention.

[0068] FIGS. 4A and 4B illustrate the breaking operation of a composite arc-type gas circuit breaker (100) according to the first embodiment in a state of fault current of a gas-insulated switchgear. For example, the composite arc-type gas circuit breaker (100) according to the first embodiment can perform the breaking operation while sequentially transforming from the state illustrated in FIG. 1 to the states illustrated in FIGS. 4A and 4B. Hereinafter, FIG. 1 will be referred to in describing FIGS. 4A and 4B.

[0069] Referring to FIGS. 4A and 4B, when the movable part (120) moves relative to the fixed arc contact (110) during the blocking operation, the fixed arc contact (110) and the movable arc contact (130) may be separated. For example, the movable part (120) may move rearward relative to the fixed arc contact (110), and accordingly, the movable arc contact (130), nozzles (150, 160), and cylinder (140) may be separated from the fixed arc contact (110). Furthermore, according to various embodiments, the fixed arc contact (110) may move in the opposite direction to the movable part (120).

[0070] When the movable arc contact (130) and the fixed arc contact (110) are separated by the movement of the movable part (120), an arc is generated inside the nozzle (150, 160). The arc may be generated between the movable arc contact (130) and the fixed arc contact (110). For example, the arc is formed to connect the movable arc contact (130) and the fixed arc contact (110).

[0071] When an arc occurs, the gas between the arc contacts is heated by the heat of the arc, generating thermal gas. The thermal gas flows through the path (P) of the nozzle (150, 160) due to the force of the arc generation and flows into the thermal expansion chamber (141). As the thermal gas flows into the thermal expansion chamber (141), the pressure inside the thermal expansion chamber (141) increases, and as the current decreases, the pressure in the arc area decreases, and the gas inside the thermal expansion chamber is discharged to the arc generation area to extinguish the arc.

[0072] When an arc occurs, at least a portion of the hot gas can flow into the thermal expansion chamber (141) through the communication hole (154) of the main nozzle (150). In addition, at least a portion of the hot gas can flow into the thermal expansion chamber (141) while being guided by the second portion (152) of the main nozzle (150) while flowing in the flow path (P).

[0073] At least a portion of the hot gas may be introduced (e.g., flow indicated by a dotted line in FIGS. 4A and 4B) into the rear space of the thermal expansion chamber (141), i.e., a space close to the bulkhead (e.g., bulkhead (145) in FIG. 1), as guided by the second portion (152). As the hot gas is introduced rearward, the cold gas that was inside the thermal expansion chamber (141) is pushed and moved into the front space of the thermal expansion chamber (141), i.e., the upper space of the second portion (152) of the main nozzle (150) or the space close to the inner wall (143) at the front end of the cylinder (140). Accordingly, the cold gas located on the upper side of the second portion (152) can be smoothly discharged along the communication hole (154) connected to the inner wall (143).

[0074] At least a portion of the hot gas may flow into the inner wall (143) of the front end of the cylinder (140) through the communication hole (154). In this case, when the cold gas is discharged, the hot gas that entered the communication hole (154) is discharged first, and then the cold gas on the upper side of the second portion (152) is discharged. Accordingly, as the cold gas is discharged after the hot gas is discharged, the point in time at which the cold gas is discharged can be adjusted to correspond to the current zero point.

[0075]

[0076] Fig. 5 is a cross-sectional view of a composite arc-type gas circuit breaker (200) according to a second embodiment of the present invention. Fig. 6 is a perspective view of a main nozzle (250) of a composite arc-type gas circuit breaker (200) according to a second embodiment of the present invention. Fig. 7 is a cross-sectional view of a main nozzle (250) of a composite arc-type gas circuit breaker (200) according to a second embodiment of the present invention.

[0077] Fig. 5 illustrates a composite arc-type gas circuit breaker (200) according to a second embodiment in a state of normal current of a gas-insulated switchgear. Fig. 6 illustrates a main nozzle (250) of a composite arc-type gas circuit breaker (200) according to the second embodiment illustrated in Fig. 5, and Fig. 7 illustrates a cross-section II-II' of the main nozzle (250) illustrated in Fig. 6.

[0078] Referring to FIGS. 5 to 7, a composite arc-type gas circuit breaker (200) according to a second embodiment of the present invention may include a fixed arc contact (210) and a movable part (220). The movable part (220) may include a movable arc contact (230), a cylinder (240), and a nozzle (250, 260). The nozzle (250, 260) may include a main nozzle (250) and an auxiliary nozzle (260). The main nozzle (250) may include a first part (251) and a second part (252).

[0079] The composite arc-type gas circuit breaker (200) and main nozzle (250) according to the second embodiment illustrated in FIGS. 5 to 7 are modified or changed from the composite arc-type gas circuit breaker (100) and main nozzle (150) according to the first embodiment described with reference to FIGS. 1 to 3, and thus the description of the first embodiment can be applied in the same manner. Hereinafter, in describing FIGS. 5 to 7, the modified portions will be described, and the same description will be omitted and replaced with the previous description.

[0080] The composite small-circuit type gas circuit breaker (200) according to the second embodiment may be modified so that, compared to the composite small-circuit type gas circuit breaker (100) according to the first embodiment, the communication holes (254) provided in the main nozzle (250) are formed in multiple rows instead of one row.

[0081] The communication hole (254) may include a first communication hole (255) and a second communication hole (256) formed parallel to the first communication hole (255). The first communication hole (255) and the second communication hole (256) may be formed in the second part (252) of the main nozzle (250). The first communication hole (255) and the second communication hole (256) may be arranged at a specified interval along the longitudinal direction of the main nozzle (250).

[0082] The first communication hole (255) may be formed at a position adjacent to the boundary between the first part (251) and the second part (252) of the main nozzle (250), and the second communication hole (256) may be formed at a position spaced apart from the first communication hole (255) by a specified distance in the direction toward the end of the second part (252). The second communication hole (256) may be formed at a position further away from the first communication hole (255) than the first communication hole (255).

[0083] Each of the first communication hole (255) and the second communication hole (256) may be formed along the outer circumferential surface of the main nozzle (250), and at least two or more may be formed. For example, two or more first communication holes (255) may be formed to be spaced apart from each other along the circumferential direction in the second part (252) of the main nozzle (250). In addition, two or more second communication holes (256) may be formed to be spaced apart from each other along the circumferential direction in the second part (252) of the main nozzle (250).

[0084] The first communication hole (255) and the second communication hole (256) may be formed at positions corresponding to each other in the longitudinal direction of the main nozzle (250). The first communication hole (255) and the second communication hole (256) may be formed such that the holes constituting each overlap each other in the longitudinal direction of the main nozzle (250) (e.g., in the direction parallel to the central axis (C)).

[0085] According to the illustrated embodiment, each of the first communication hole (255) and the second communication hole (256) may include four holes (or long holes) having an arc shape, and the four holes constituting the first communication hole (255) and the four holes constituting the second communication hole (256) may be arranged to overlap in the longitudinal direction of the main nozzle (250). However, the illustrated embodiment is exemplary, and the shape, number, and / or arrangement of the first communication hole (255) and the second communication hole (256) are not limited to those illustrated. The first communication hole (255) and the second communication hole (256) may be formed in two or more, but may be designed in an appropriate number in consideration of the durability and structural stability of the main nozzle (250), and the holes constituting each may be formed to be arranged to be misaligned in the longitudinal direction of the main nozzle (250).

[0086] The first communication hole (255) and the second communication hole (256) can communicate and connect the flow path (P) of the thermal expansion chamber (241) and the nozzle (250, 260). For example, the first communication hole (255) and the second communication hole (256) can communicate and connect the flow path (P) of the nozzle (250, 260) and the internal space of the thermal expansion chamber (241) located on the outer surface of the second part (252) in a direction perpendicular to the central axis (C).

[0087] The first communication hole (255) and the second communication hole (256) may be formed at a position adjacent to the inner wall (243) of the thermal expansion chamber (241). The first communication hole (255) and the second communication hole (256) may be formed adjacent to the inner wall (243) of the thermal expansion chamber (241) based on the center line (L) of the second part (252). Here, the center line (L) of the second part (252) may be defined as a line that bisects the length of the second part (252) as a vertical bisector of the second part (252).

[0088] As illustrated in FIG. 5, the first communication hole (255) and the second communication hole (256) may be positioned to the right with respect to the center line (L) of the second portion (252). Here, the right side refers to the direction toward the first portion (251), that is, the second communication hole (256) may be formed at a position spaced apart from the center line (L) of the second portion (252) by a predetermined distance in the direction toward the first portion (251), and the first communication hole (255) may be formed at a position spaced apart from the second communication hole (256) by a predetermined distance in the direction toward the first portion (251). Accordingly, the distance between the second communication hole (256) and the inner wall (243) may be shorter than half the length of the second portion (252).

[0089] The first communication hole (255) may be provided so that at least a portion thereof is connected to the inner wall (243) of the thermal expansion chamber (241). The first communication hole (255) may be partially connected to the inner wall (243) of the front end of the cylinder (240) forming the thermal expansion chamber (241). For example, the first communication hole (255) may be formed at a position that can be connected to the inner wall (243) of the second portion (252) of the main nozzle (250).

[0090] The first communication hole (255) may have a first inner surface (255a) and a second inner surface (255b) facing each other in the longitudinal direction of the main nozzle (250). The first communication hole (255) may be configured such that the first inner surface (255a) is positioned on the same surface or on the same line as the inner wall (243) of the thermal expansion chamber (241). For example, the first inner surface (255a) of the first communication hole (255) may be connected to the inner wall (243) of the front end of the cylinder (240) while forming the same surface.

[0091] A gas circuit breaker (200) according to the second embodiment is provided with a first communication hole (255) in the main nozzle (250) corresponding to the communication hole (154) provided in the main nozzle (150) of the gas circuit breaker (100) according to the first embodiment, and may additionally be provided with a second communication hole (256) located further inside the thermal expansion chamber (241) than the first communication hole (255).

[0092] According to the illustrated embodiment, the communication hole (254) is composed of a first communication hole (255) and a second communication hole (256) that are formed in two rows along the longitudinal direction of the main nozzle (250). However, if the communication hole (254) is formed in multiple rows, it is not necessarily limited to two rows.

[0093]

[0094] FIG. 8a and FIG. 8b are drawings illustrating the blocking operation of a composite gas circuit breaker (200) according to the second embodiment of the present invention.

[0095] FIGS. 8A and 8B illustrate the breaking operation of a composite arc-type gas circuit breaker (200) according to the second embodiment in a state of fault current of a gas-insulated switchgear. For example, the composite arc-type gas circuit breaker (200) according to the second embodiment can perform the breaking operation while sequentially transforming from the state illustrated in FIG. 5 to the states illustrated in FIGS. 8A and 8B. Hereinafter, FIG. 5 will be referred to in describing FIGS. 8A and 8B.

[0096] In addition, the blocking operation of the composite small-circuit gas circuit breaker (200) according to the second embodiment may be substantially the same as or similar to the blocking operation of the composite small-circuit gas circuit breaker (100) according to the first embodiment. Hereinafter, redundant descriptions are omitted.

[0097] Referring to FIGS. 8A and 8B, when the movable part (220) moves with respect to the fixed arc contact (210) during the blocking operation, the fixed arc contact (210) and the movable arc contact (230) may be separated. When the movable arc contact (230) and the fixed arc contact (210) are separated, an arc may occur between the movable arc contact (230) and the fixed arc contact (210). When an arc occurs, thermal gas is generated by the heat of the arc, and the thermal gas flows through the flow path (P) of the nozzle (250, 260) due to the force of the arc generation and flows into the thermal expansion chamber (241). As the thermal gas flows into the thermal expansion chamber (241) and the current decreases, the gas inside the thermal expansion chamber (241) is discharged to the arc generation area to extinguish the arc.

[0098] When an arc occurs, at least a portion of the hot gas can flow into the thermal expansion chamber (241) through the communication hole (254) of the main nozzle (250). In addition, at least a portion of the hot gas can flow into the thermal expansion chamber (241) while being guided by the second portion (252) of the main nozzle (250) while flowing in the flow path (P).

[0099] At least a portion of the hot gas may flow into the inner wall (243) of the front end of the cylinder (240) through the first communication hole (255) and the second communication hole (256). In the case of the second embodiment (200) having two rows of the first communication holes (255) and the second communication holes (256), the amount of hot gas flowing into the communication holes (254) may be greater than that of the first embodiment (100) having one row of communication holes (254). In particular, the amount of hot gas flowing into the first communication hole (255) connected to the inner wall (243) may be greater than the amount of hot gas flowing into the communication hole (254) connected to the inner wall (243) in the first embodiment (100).

[0100] As in the second embodiment (200), the main nozzle (250) includes a second part (252) that extends into the inside of the thermal expansion chamber (241), and the second part (252) is provided with two rows of communication holes (254), so that hot gas flows into the rear of the thermal expansion chamber (241) and cold gas inside the thermal expansion chamber (241) moves to the front space of the thermal expansion chamber (241), so that the discharge of cold gas can be smooth.

[0101] As the communication holes (254) are arranged in two rows as in the second embodiment (200), the flow rate of hot gas flowing into the thermal expansion chamber (241) increases compared to the case where the communication holes (254) are arranged in one row, thereby increasing the pressure of the thermal expansion chamber, and increasing the flow rate of cold gas discharged to the arc area at the time of current zero, thereby lowering the temperature. Through this, the interruption performance of the gas circuit breaker can be improved.

[0102]

[0103] FIG. 9a, FIG. 9b, FIG. 9c and FIG. 9d are drawings showing various modified examples of the communication hole (254) of the composite small-capacity gas circuit breaker (200) according to the second embodiment of the present invention.

[0104] Hereinafter, various modifications of the communication hole (254) of the composite small-circuit type gas circuit breaker (200) according to the second embodiment will be described with reference to FIGS. 9a, 9b, 9c and 9d, and FIGS. 5 to 7 will be referred to together when describing FIGS. 9a, 9b, 9c and 9d.

[0105] Meanwhile, FIGS. 9a, 9b, 9c and 9d illustrate the modified form of the communication hole based on the composite arc-type gas circuit breaker (200) according to the second embodiment, but the following description can be equally applied to the communication hole (154) of the composite arc-type gas circuit breaker (100) according to the first embodiment.

[0106] Referring to FIGS. 9a and 9b, the position of the first communication hole (255) located adjacent to the inner wall (243) of the cylinder (240) can be varied. The first communication hole (255) can be spaced apart from the inner wall (243) or can overlap with the inner wall (243). For example, the first inner surface (255a) of the first communication hole (255) can be connected to the inner wall (243) at a step.

[0107] As illustrated in Fig. 9a, the first communication hole (255) may be formed so that the first inner surface (255a) is spaced apart from the inner wall (243) by a predetermined distance in the direction toward the second communication hole (256). In addition, as illustrated in Fig. 9b, the first communication hole (255) may be formed so that the inner wall (243) is positioned between the first inner surface (255a) and the second inner surface (255b).

[0108] Referring to FIGS. 9c and 9d, the shape of the communication hole (255, 256) can be changed in various ways.

[0109] As illustrated in Fig. 9c, the first communication hole (255') may be formed in a tapered shape that becomes narrower as it goes toward the inside of the main nozzle (250). For example, the first communication hole (255') may have a shape in which the width gradually becomes narrower as it goes toward the central axis (C) and may penetrate the outer and inner surfaces of the main nozzle (250). Accordingly, as the radius of the main nozzle (250) increases, the cross-sectional area of ​​the first communication hole (255') becomes wider in proportion to the radius and width.

[0110] Meanwhile, Fig. 9c illustrates an embodiment in which the shape of the first communication hole (255') is deformed, but the tapered shape of the first communication hole (255') illustrated in Fig. 9c can also be applied to the second communication hole (256). In addition, the first communication hole (255) may not be deformed and maintain the shape illustrated in Fig. 5, and the second communication hole (256) may be deformed into a tapered shape.

[0111] As illustrated in FIG. 9d, the first communication hole (255'') may be formed in a shape that slopes toward the arc region as it goes toward the inside of the main nozzle (250). For example, the first communication hole (255'') may be formed in a shape that slopes at a predetermined slope toward the first part (251) of the main nozzle (250) or toward the outside of the cylinder (240) as it goes toward the central axis (C), and may penetrate the outer and inner surfaces of the main nozzle (250).

[0112] Meanwhile, Fig. 9d illustrates an embodiment in which the shape of the first communication hole (255'') is deformed, but the inclined shape of the first communication hole (255'') illustrated in Fig. 9c can also be applied to the second communication hole (256). In addition, the first communication hole (255) may not be deformed and maintain the shape illustrated in Fig. 5, and only the second communication hole (256) may be deformed into an inclined shape.

[0113] According to various embodiments, the main nozzle (250) may be provided in a form in which the modified example of FIG. 9c and the modified example of FIG. 9d are combined. For example, one of the first communication hole (255) and the second communication hole (256) may be formed in a tapered shape (e.g., shape of 255') as in FIG. 9c, and the other of the first communication hole (255) and the second communication hole (256) may be formed in an inclined shape (e.g., shape of 255'') as in FIG. 9d.

[0114]

[0115] FIG. 10 is a graph showing the thermal expansion chamber pressure that can predict the blocking performance of a composite arc-type gas circuit breaker (100) according to the first embodiment of the present invention and a composite arc-type gas circuit breaker (200) according to the second embodiment of the present invention.

[0116] The graph in Fig. 10 is a graph showing the thermal expansion chamber pressure over time obtained by CFD arc analysis, and the point where the four lines (P1 to P4) in the graph end corresponds to the current zero point.

[0117] The line indicated as P1 in the graph represents the thermal expansion chamber pressure of the gas circuit breaker according to the first comparative example in which no communication hole is formed in the main nozzle, the line indicated as P2 represents the thermal expansion chamber pressure of the gas circuit breaker (100) according to the first embodiment, the line indicated as P3 represents the thermal expansion chamber pressure of the gas circuit breaker according to the second comparative example in which there are two communication holes (255, 256), but one of the two communication holes (e.g., the second communication hole (256)) is formed inside the thermal expansion chamber with respect to the center line of the main nozzle, and the line indicated as P4 represents the thermal expansion chamber pressure of the gas circuit breaker (200) according to the second embodiment.

[0118] For example, the gas circuit breaker according to the first comparative example may have a structure in which the communication hole (154) is omitted from the main nozzle (150) in the gas circuit breaker (100) according to the first embodiment illustrated in FIG. 1. In addition, the gas circuit breaker according to the second comparative example may have a structure in which the position of the first communication hole (255) is the same as that of the gas circuit breaker (200) according to the second embodiment illustrated in FIG. 5, but the second communication hole (256) is located to the left with respect to the center line (L) of the second part (252).

[0119] The graph in Fig. 10 shows an interpretation for a case where the arcing time is approximately 23 ms. Since the higher the pressure in the thermal expansion chamber (141; 241), the more insulating gas is discharged, it can be interpreted that the higher the maximum pressure in the thermal expansion chamber (141; 241) or the higher the pressure in the thermal expansion chamber (141; 241) at the current zero point, the better the blocking performance.

[0120] According to the graph of Fig. 10, the maximum pressure of the thermal expansion chamber and the pressure of the thermal expansion chamber at the current zero point in the gas circuit breaker for each of the first comparative example, the second comparative example, the first embodiment, and the second embodiment can be expressed as shown in Table 1 below.

[0121] Arcing time 23ms Example 1 Comparative example 2 Comparative example 1 Example 2 Example Maximum pressure in thermal expansion chamber [bar] 69.467.869.770.4 Pressure in thermal expansion chamber at zero current point [bar] 52.354.155.956.3

[0122] Referring to the graph of FIG. 10 and Table 1 above, it can be confirmed that in the first embodiment and the second embodiment, the maximum pressure of the thermal expansion chamber (141; 241) and the pressure of the thermal expansion chamber (141; 241) at the current zero point are higher than in the first comparative example and the second comparative example. That is, it can be seen that when one or more communication holes (154; 254) are formed on the first part (151; 251) side from the center line (L) of the second part (152; 252) of the main nozzle (150; 250) (e.g., on the right side of the center line (L) of the second part (152; 252) in FIGS. 1 and 5), the flow inside the thermal expansion chamber becomes smooth and the gas flow rate increases, thereby improving the blocking performance. Comparing the first embodiment and the first comparative example, it can be seen that the blocking performance is improved as the communication holes (154) are formed on the right side of the center line (L).

[0123] Comparing the first embodiment and the second comparative example, it can be confirmed that the blocking performance is superior when one row of communication holes (154) is formed on the right side of the center line (L) than when another communication hole is additionally formed on the left side of the center line (L) to form two rows of communication holes.

[0124] Comparing the second embodiment and the second comparative example, it can be confirmed that the blocking performance is superior when two communication holes (255, 256) are formed, but both communication holes (255, 256) are formed on the right side of the center line (L) rather than when the two communication holes (255, 256) are formed on both sides of the center line (L). That is, in addition to the first communication hole (255), the blocking performance is improved when the second communication hole (256) is formed on the right side of the center line (L) rather than when it is formed on the left side of the center line (L).

[0125] In addition, when comparing the first embodiment and the second embodiment, it can be confirmed that the blocking performance is superior because the maximum pressure of the thermal expansion chamber and the pressure of the thermal expansion chamber at the current zero point are higher in the case where the communication holes are formed in two rows than in the case where the communication holes are formed in one row within the range where the communication holes are formed on the right side of the center line (L).

[0126] Meanwhile, the graph of FIG. 10 and Table 1 compare the thermal expansion chamber pressures for the first comparative example, the second comparative example, the first embodiment, and the second embodiment under predetermined conditions, and the embodiments of the present invention are not limited by the graph of FIG. 10 and the interpretation results of Table 1.

[0127] The present invention is not limited to the embodiments described above, and may include a combination of the above embodiments or a combination of at least one of the above embodiments and a known technology as another embodiment.

[0128] Although the above has been described with reference to embodiments, it will be understood by those skilled in the art that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

[0129] The present invention is useful for safely protecting a system by safely blocking an accident current in a high-voltage power system.

Claims

1. Fixed arc contact; A cylinder having a thermal expansion chamber; a movable arc contact, at least a portion of which is disposed within said cylinder and arranged such that said fixed arc contact is partially inserted therein; and Main nozzle coupled to the above cylinder Including, A composite arc-type gas circuit breaker, wherein the main nozzle is provided such that a portion thereof is positioned inside the thermal expansion chamber, and a communication hole communicating with the thermal expansion chamber is provided in a portion of the main nozzle located inside the thermal expansion chamber.

2. In paragraph 1, The above main nozzle comprises a first part located outside the cylinder, and a second part extending from the first part into the thermal expansion chamber, A composite gas circuit breaker, wherein the above-mentioned communication hole is formed in at least a part of the second part.

3. In paragraph 2, A composite arc-type gas circuit breaker, wherein the above-mentioned communication hole is formed on one side where the first part is located based on a center line that bisects the length of the second part.

4. In paragraph 2, The above main nozzle is coupled to the front end of the cylinder, A composite arc-type gas circuit breaker, wherein the above-mentioned communication hole is formed so as to be connected to the inner wall of the front end of the cylinder forming the above-mentioned thermal expansion room at least in part.

5. In paragraph 4, A composite gas circuit breaker, wherein the first inner surface adjacent to the first portion among the inner surfaces facing each other of the above-mentioned chimneys is connected to the inner wall.

6. In paragraph 5, A composite gas circuit breaker in which the above-mentioned communication hole is formed so that the first inner surface is positioned on the same line as the inner wall.

7. In paragraph 2, A composite small-bore gas circuit breaker, wherein the above-mentioned communication hole includes a first communication hole and a second communication hole arranged along the longitudinal direction of the main nozzle.

8. In paragraph 7, A composite arc-type gas circuit breaker, wherein the first communication hole and the second communication hole are formed on one side where the first part is located based on a center line that bisects the length of the second part.

9. In paragraph 8, The above second communication hole is formed at a position spaced apart from the center line by a predetermined distance in the one direction, A composite gas circuit breaker, wherein the first communication hole is formed at a position spaced apart from the second communication hole in the one direction by a predetermined distance.

10. In paragraph 2, Further comprising an auxiliary nozzle arranged inside the main nozzle so as to partially surround the above movable arc contact, A composite arc-type gas circuit breaker, in which a path for gas to flow is formed between the main nozzle and the auxiliary nozzle.

11. In paragraph 10, A composite arc-type gas circuit breaker in which the above-mentioned communication hole connects a part of the space surrounding the outer surface of the second part of the above-mentioned thermal expansion room and a part of the space of the above-mentioned path in a direction perpendicular to the longitudinal direction of the above-mentioned main nozzle.

12. In paragraph 1, The above-mentioned communication hole is a composite arc-type gas circuit breaker including two or more long holes spaced apart along the circumferential direction on the outer surface of the main nozzle.

13. In paragraph 1, A composite arc-type gas circuit breaker in which the above-mentioned communication hole is formed in a shape in which the width or cross-sectional area becomes narrower from the outer surface of the main nozzle to the inner surface.

14. In paragraph 1, A composite arc-type gas circuit breaker, wherein the above-mentioned communication hole is formed in a shape that is inclined in the direction in which the main nozzle protrudes from the cylinder as it goes from the outer surface of the main nozzle to the inner surface.

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