High voltage circuit breaker with particle trap

Abstract

The present invention relates to a high-voltage circuit breaker having a particle trap. A high-voltage circuit breaker (1) has a first main contact (2) and a second main contact (3) that extend along a central longitudinal axis (A) and are at least partially surrounded by an insulator (5), the insulator (5) has an inner surface (18) that faces the central longitudinal axis (A) and is positioned at a first distance (d1) from the central longitudinal axis (A), and the high-voltage circuit breaker further includes at least one particle trap (8, 9) for trapping particles generated during the operation of the circuit breaker, the particle trap (8, 9) has an inner surface (19) that faces the central longitudinal axis (A) and is positioned at a second distance (d2) from the central longitudinal axis (A), the second distance (d2) being greater than the first distance (d1).

Description

Technology Field

[0001] The present invention relates to a high-voltage circuit breaker. The circuit breaker may be, for example, part of a gas-insulated switchgear. Background Technology

[0002] Particles can be generated in circuit breakers during mechanical switching and the occurrence of power shots. As an example, these particles may be metal particles generated from the mechanical interaction of movable parts. Additionally, dust may accumulate in the circuit breaker. These particles and dust can accumulate on the surface of the insulator and lead to the deterioration or even bridging of the insulation gap.

[0003] US Publication 2011 / 0180514 A1 discloses a gas-insulated switchgear having an insulating case that accommodates fixed and movable contacts of the switchgear. The insulating case has a flange on its inner circumference, and the flange has a collecting groove formed therein to collect metal particles generated during the contact or separation operation of the contacts.

[0004] The embodiments of the present disclosure relate to an improved high-voltage circuit breaker.

[0005] According to a first embodiment, a high-voltage circuit breaker comprises a first main contact and a second main contact extending along a central longitudinal axis, and comprises an insulator that at least partially surrounds the contacts. The insulator has an inner surface facing the central longitudinal axis, and the inner surface is arranged at a first distance from the central longitudinal axis. The insulator may have, for example, a tubular shape. The circuit breaker comprises at least one particle trap for trapping particles generated during the operation of the circuit breaker, said particle trap having an inner surface facing the central longitudinal axis and arranged at a second distance from the central longitudinal axis, and the second distance is greater than the first distance.

[0006] Therefore, the particle trap is positioned radially outward with respect to the insulator. Due to this external position, particles can be firmly trapped, preventing them from escaping the particle trap during internal movement or vibration of the circuit breaker.

[0007] The circuit breaker may include at least one insulating flange for coupling the insulator to additional parts of the circuit breaker. For example, the insulating flange may establish coupling to the contact supports of the circuit breaker. The contact supports support the first and / or second main contacts of the circuit breaker. A particle trap may be formed by the insulating flange. The insulating flange may be located on the outer surface of the insulator, and the outer surface is oriented away from the central longitudinal axis.

[0008] Therefore, the insulator flange can have a dual function of joining the insulator to the contact supports and collecting particles generated during operation. The insulator flange may include a joining portion for joining to the contact supports. The particle trap can be separated from the joining portion. Therefore, the particle trap itself does not have the dual function of collecting and joining particles.

[0009] A particle trap may include an inlet through which particles can enter, and the inlet is located at the axial end of the insulator. The particle trap may be closed to the outside of a circuit breaker to prevent particles from escaping the trap outward. The particle trap may be accessible only through the inlet.

[0010] The particle trap may contain a pocket, which is located behind the insulator when viewed radially outward from the central longitudinal axis. In this case, particles cannot easily move back from the pocket toward the inner surface of the insulator.

[0011] The pocket can be shielded from the electric field by a metal shield located between the pocket and the insulator. This prevents particles from being drawn out of the particle trap by the electric field. The metal shield can be formed by an insulator flange.

[0012] The particle trap is located at the lowest part of the insulator flange, but can be located at the lowest point in terms of gravity from the installation location of the circuit breaker. As a result, particles can enter the particle trap by gravity, and are prevented from leaving the particle trap by gravity.

[0013] The circuit breaker may include at least two particle traps located at opposing axial ends of the insulator. Each particle trap may be formed by a flange and may have any functional and structural features as described above.

[0014] Additional features, improvements, and workarounds become apparent from the following description of exemplary embodiments associated with the drawings. In the drawings, elements of the same structure and / or function may be referred to by the same reference numerals. It should be understood that the embodiments depicted in the drawings are exemplary representations and are not necessarily drawn to scale. Brief explanation of the drawing

[0015] FIG. 1 is a cross-sectional view of one embodiment of a high-voltage circuit breaker having a particle trap. Figure 2 is a perspective view of one embodiment of a particle trap. Specific details for implementing the invention

[0016] FIG. 1 shows a cross-sectional view of a high-voltage circuit breaker (1). The circuit breaker (1) may be part of a gas-insulated switchgear.

[0017] The circuit breaker (1) includes a first main contact (2) and a second main contact (3). The first main contact (2) and the second main contact (3) can be moved from a closed state, where the main contacts (2, 3) are electrically in contact with each other, to an open state, where the electrical connection is disconnected. The first main contact (2) may be, for example, a movable contact, and the second main contact (3) may be, for example, a fixed contact. The circuit breaker (1) further includes a first arc contact (22) and a second arc contact (23) for extinguishing an electric arc that may be formed between the main contacts (2, 3) during the separation of the main contacts (2, 3). An open state of the circuit breaker (1) is illustrated in FIG. 1.

[0018] The main contacts (2, 3) extend along the central longitudinal axis (A). To open or close the main contacts (2, 3), the main contacts (2, 3) move toward each other or move in opposite directions along the central longitudinal axis (A).

[0019] The main contacts (2, 3) are at least partially surrounded by an insulator (5) in both the open and closed states. The insulator (5) has a tubular shape. The insulator (5) may be permanently fixed to the contact supports (6, 7) of the first main contact (2) and the second main contact (3) by flanges (10, 11). The first main contact (2) may be axially movable with respect to the contact supports (6, 7), and the second main contact (3) may be fixed with respect to the contact supports (6, 7). The first contact support (6) is a support for the first main contact (2), and the second contact support (7) is a support for the second main contact (3). The contact supports (6, 7) may be current-carrying components.

[0020] The insulator (5) has an inner surface (18) oriented toward the central longitudinal axis (A) and arranged at a first distance (d1) from the central longitudinal axis (A).

[0021] Conductive particles may be generated, for example, due to friction at the main contacts (2, 3) during mechanical switching and power shots. Particles and also dust may accumulate within the gas-filled insulation gap (4) and on surfaces inside the circuit breaker (1). The particles or dust may vary in size, conductivity, and material, for example. Depending on the amount, size, and location of the particles, they may cause flash-over. For example, particles may accumulate on the surface of the insulator (5) and cause a degradation of the insulation function.

[0022] To avoid the accumulation of particles at locations leading to flash-over, particle traps (8, 9) are provided in the insulator (5). The particle traps (8, 9) are configured to collect and capture particles so that the insulator (5) and the entire circuit breaker (1) are kept clean from particles, particularly near the insulation gap (4).

[0023] Particle traps (8, 9) are incorporated into insulator flanges (10, 11) located at opposite ends of the insulator (5). The insulator flanges (10, 11) are configured to secure the insulator (5) to the contact support (6, 7). The insulator flanges (10, 11) surround the insulator (5) at both axial ends of the insulator (5). The insulator flanges (10, 11) are directly adjacent to the outer surface of the insulator (5), and the outer surface is oriented away from the central longitudinal axis (A). The insulator flanges (10, 11) are also adjacent to the axial end faces of the insulator (5).

[0024] In the following, the structure of the insulating flanges (10, 11) and particle traps (8, 9) is described in more detail with reference to one insulating flange (10) and one particle trap (8). However, the structure may be the same for other insulating flanges (11) and particle traps (9).

[0025] The particle trap (8) has an inner surface (19) facing the central longitudinal axis (A), and the inner surface (19) is arranged at a second distance (d2) from the central longitudinal axis (A). The second distance (d2) is greater than the first distance (d1).

[0026] The particle trap (8) is accessible to particles coming from the insulation gap (4) through the inlet (13). The inlet (13) is located beyond the axial end of the insulator (5). The inlet (13) is radially outwardly defined by the outer wall (14) of the flange (10). In the axial direction away from the insulator (5), the inlet (13) is defined by the contact support (6), and in the axial direction toward the insulator (5), the inlet (13) is defined by the insulator (5).

[0027] The particle trap (8) further includes a pocket (15) formed by an undercut in the flange (11). The pocket (15) is located beyond the insulator (5) when viewed from the central longitudinal axis (A).

[0028] The insulator (5) may be formed from an insulating material such as insulating paper. The insulator flange (10, 11) may be formed from metal. As an example, the insulator flange (10, 11) may include or be composed of aluminum. Thus, a metal shield (19) that electrically shields the particle trap (8) is provided. It is also possible for the metal shield (19) to be formed by a separate part. In particular, the particle trap (8) is shielded at least partially from the electric field inside the circuit breaker (1), thereby preventing particles from being drawn out of the particle trap (8) by the electric field.

[0029] FIG. 2 illustrates details of an insulator flange (10) and an insulator (5) having an integrated particle trap (8). An inlet (13) is formed by a recess within the inner wall (16) of the insulator flange (10). Thus, the inner wall (16) is recessed axially with respect to the outer wall (14).

[0030] As can be seen in FIG. 2, the insulator flange (10) includes a coupling portion (12) for coupling the insulator (5) to the contact support portion (6). The coupling portion (12) may include, for example, a receiving hole for a bolt connection.

[0031] The particle trap (8) may be located only in a limited radial section of the circumferential flange (10) as shown in FIG. 2, or may be arranged circumferentially along the entire flange (10). Additionally, each flange (10, 11) may include multiple particle traps (8) located at different angular positions with respect to the longitudinal axis (A). The particle trap (8, 9) may be located at least at the lowest part of the flange (10, 11), that is, at the lowest part in terms of gravity at the installation location of the circuit breaker (1).

[0032] Particles generated from the main contacts (2, 3), etc., inside the circuit breaker (1) may fall onto the insulator (5). Due to mechanical motion, vibration, or gas flow, the particles are pushed out from the sides of the insulator (5) and enter the pocket (15) through the inlet (13) by gravity. Due to mechanical motion and vibration, the particles enter at least partially into the pocket (15) where they can be safely accumulated. Additionally, the pocket (15) may have a concave shape with respect to adjacent parts of the flange (10), which can further prevent the particles from leaving the pocket (15).

[0033] Overall, the particle trap (8) reliably captures particles so that the insulation is not degraded and the performance of the circuit breaker (1) is improved. Explanation of the symbols

[0034] 1 High-voltage circuit breaker 2. 1st main contact 3 Second main contact 4 insulation gap 5 Insulators 6 contact support 7 contact support 8 particle traps 9 Particle Trap 10 insulator flanges 11 Insulator flange 12 connecting parts 13 Entrance 14 exterior wall 15 pockets 16 inner wall 18 Inner surface of the insulator 19 Inner surface of the particle trap 20 External surface of the insulator 21 Metal Shield 22 1st arc contact 23 Second arc contact d1 Distance of the inner surface of the insulator to the center longitudinal axis d2 Distance of the inner surface of the particle trap to the center longitudinal axis

Claims

Claim 1 As a high-voltage circuit breaker (1), the circuit breaker has a first main contact (2) and a second main contact (3) that extend along a central longitudinal axis (A) and are at least partially surrounded by an insulator (5); the insulator (5) has an inner surface (18) that faces the central longitudinal axis (A) and is positioned at a first distance (d1) from the central longitudinal axis (A); the circuit breaker includes at least one particle trap (8, 9) for trapping particles generated during the operation of the circuit breaker; the particle trap (8, 9) has an inner surface (19) that faces the central longitudinal axis (A) and is positioned at a second distance (d2) from the central longitudinal axis (A), the second distance (d2) being greater than the first distance (d1); and the high-voltage circuit breaker (1) has the insulator (5) the circuit A high-voltage circuit breaker (1) comprising at least one insulating flange (10, 11) for coupling to additional parts of the circuit breaker (1), wherein the particle trap (8, 9) is formed by the insulating flange (10, 11). Claim 2 delete Claim 3 In claim 1, the insulator flange (10, 11) is located on the outer surface (20) of the insulator (5), and the outer surface (20) is oriented away from the central longitudinal axis (A), high voltage circuit breaker (1). Claim 4 A high-voltage circuit breaker (1), wherein, in claim 1 or 3, the particle trap (8, 9) comprises a pocket (15), and the pocket (15) is located behind the insulator (5) when viewed radially outward from the central longitudinal axis (A). Claim 5 In claim 4, the pocket (15) is shielded from an electric field by a metal shield (21) located on the outer surface (20) of the insulator (5), in a high-voltage circuit breaker (1). Claim 6 In claim 5, the metal shield (21) is formed by an insulating flange (10, 11), a high-voltage circuit breaker (1). Claim 7 In claim 1 or 3, the particle trap (8, 9) includes an inlet (13) capable of introducing particles into the particle trap (8, 9), and the inlet is located at the axial end of the insulator (5), a high-voltage circuit breaker (1). Claim 8 In claim 1 or 3, the particle trap (8, 9) is radially limited by the inner wall (16) and outer wall (14) of the insulator flange (10), and the inner wall (16) is recessed along the central longitudinal axis (A) with respect to the outer wall (14), high voltage circuit breaker (1). Claim 9 delete Claim 10 A high-voltage circuit breaker (1) comprising at least two particle traps (8, 9) located at opposite axial ends of the insulator (5) according to claim 1 or 3. Claim 11 In claim 1 or 3, the particle trap (8, 9) is located at the lowest part of the insulator flange (10), and the lowest part is at the lowest part in terms of gravity from the installation location of the circuit breaker (1), high voltage circuit breaker (1).

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