CN112397338A

CN112397338A - Ventilation insulation member for interrupter unit

Info

Publication number: CN112397338A
Application number: CN202010818637.7A
Authority: CN
Inventors: D·阿瓦特; K·巴维卡尔; A·豪尔; J·兰格; P·拉斯特; M·穆勒; N·谢拉尔; S·施利瓦斯塔瓦; B·辛格
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2019-08-16
Filing date: 2020-08-14
Publication date: 2021-02-23
Also published as: EP3780056A1

Abstract

The invention relates to a ventilation insulation member for an interrupter unit. An interrupter unit (200) with a ventilation insulation member (201) is provided. The interrupter unit (200) includes a housing (101) and a ventilation insulating member (201). The housing (101) comprises a non-metallic housing (101A) and a metallic housing (101B), the non-metallic housing (101A) and the metallic housing (101B) being in contact with each other such that one or more contact areas (105A, 105B) are formed therebetween. A ventilation insulating member (201) may be physically disposed on the housing (101) to accommodate at least one of the contact areas (105A, 105B) to prevent flashover caused by solder edges formed in the contact areas (105A, 105B) when brazing the metallic portion (101B) and the non-metallic portion (101A) of the housing (101).

Description

Ventilation insulation member for interrupter unit

Technical Field

The present disclosure relates to a switching device such as a circuit breaker. More particularly, the present disclosure relates to a ventilated insulating member for an interrupter unit of a circuit breaker.

Background

Conventionally, a switching device such as a circuit breaker mainly includes a switch module formed of one or more function guide units including a base module unit, a pole module unit, and a driving module unit. The pole module unit comprises an interrupter unit, for example a vacuum interrupter comprising a stationary member and a movable member. Generally, circuit breakers are switches that are used to protect the electrical circuit connected thereto from damage due to overload by their automatic operation causing interruption of the current flowing therethrough. Vacuum circuit breakers typically have a pair of electrical switch contacts disposed within a vacuum chamber. Vacuum circuit breakers interrupt the current by opening these switch contacts in a vacuum. Vacuum circuit breakers are an essential component, in particular in medium-voltage protective devices. For high voltage applications, the interrupter cell may be filled with a gas, such as SF6, for both insulation and interruption.

Fig. 1A shows a cross-sectional elevation view of a vacuum interrupter 100 according to the prior art. The vacuum interrupter 100 includes a housing 101, the housing 101 including a ceramic housing 101A and a metal housing 101B rigidly attached to each other. The housing 101 accommodates a metal vapor shield 102 therein. The metal vapor shield 102 in turn houses

electrical contacts

103A, 103B, i.e. a fixed contact 103A rigidly connected to a fixed contact stem 107A and a moving contact 103B operatively connected to a moving contact stem 107B via a bellows 104, the bellows 104 allowing the moving contact 103B to move. The moving contact guide 106 guides the movement of the moving contact 103B by means of the bellows 104. The

electrical contacts

103A and 103B are physically separated in a vacuum chamber defined within the ceramic housing 101A. Typically, the metal vapor shield 102 and the ceramic housing 101A are connected to each other in a leak-proof manner in order to maintain the vacuum within the vacuum interrupter 100. Similarly, the metal case 101B and the ceramic case 101A are connected to each other in a leak-proof manner.

During construction of the vacuum interrupter 100, the metal vapor shield 102 and the ceramic housing 101A and the metal housing 101B and the ceramic housing 101A are joined via a brazing process, which results in a solder edge (not shown) being formed in the

contact areas

105A and 105B where the metal vapor shield 102 and the ceramic housing 101A and/or the metal housing 101B and the ceramic housing 101A form a physical joint therebetween at the

contact areas

105A and 105B. These solder edges, although very small in size, typically exhibit sharp edges that result in high electric field strengths. Thus, if the dielectric distance is small, these solder edges may cause undesirable flashovers (flashovers) and risks to equipment and human life when formed on the vacuum interrupter 100.

Fig. 1B shows a perspective view of a vacuum interrupter 100 according to the prior art. The vacuum interrupter 100 has

contact areas

105A and 105B along its body, and solder edges (not shown) are formed on the

contact areas

105A and 105B due to the physical connection made during the above-described construction of the vacuum interrupter 100. These solder edges are generally formed in the area 105A toward the

distal ends

108A and 108B of the vacuum interrupter 100. However, they may also be formed along the surface 105B where the metal case 101B and the ceramic case 101A are physically connected to each other at the surface 105B.

Known techniques in the art to address the above-mentioned problems arising from the formation of a weld edge (not shown) include constructing a vacuum tube that is recast with a special material (e.g., an elastomer), shrinking a tube onto the vacuum tube or onto the weld edge itself, applying a self-adhesive tape under mechanical stress onto the weld edge, using a field control element (i.e., an electrode) through which the weld edge can be placed in a field shadow, and the like. However, these techniques are rather time consuming, design and cost intensive.

Disclosure of Invention

It is therefore an object of the present invention to provide an interrupter unit suitable for air and gas insulated applications that solves the problems caused by solder edge formation in a time efficient, design efficient and cost efficient way.

The interrupter unit disclosed herein achieves the aforementioned objects by a venting insulation member that may be physically disposed on a housing that houses at least one contact area and thus a solder rim, thereby preventing the aforementioned problems due to the formation of the solder rim.

Disclosed herein is an interrupter unit. As used herein, "interrupter unit" refers to a switch unit having electrical contacts that make or break an electrical circuit to allow or interrupt electrical current therebetween. According to one aspect, the interrupter unit is a vacuum interrupter unit that separates its electrical contacts in a vacuum having a maximum dielectric strength. The interrupter unit includes a housing. The housing comprises a non-metallic housing (e.g. a ceramic or glass housing) and a metallic housing, which are in contact with each other, forming one or more contact areas between them. As used herein, "contact area" refers to a physical point of contact between two different material parts of an interrupter unit. The contact area is, for example, a contact point between the ceramic housing and the metal housing, or a contact point between the ceramic housing and a metal vapor shield, which shields the electrical contacts of the interrupter unit, arranged inside the housing.

The interrupter unit includes a ventilation insulating member that may be physically disposed on a housing that houses at least one contact region. As used herein, a "venting insulation member" refers to a layer having an insulating material therein, and which is configured to cover one or more of the contact areas while at least partially providing venting thereto. Advantageously, the insulating ventilation member is configured as a self-collapsible cap having a circumference smaller than the circumference of the housing of the interrupter unit, such that it self-collapses over the contact area when the insulating ventilation member is stretched and aligned over the housing to cover one or more of the contact areas and released.

According to one aspect, the ventilation insulation member comprises protrusions and/or indentations along an inner surface of the ventilation insulation member. According to another aspect, the vent insulation member includes an aperture along an inner surface of the vent insulation member. These protrusions, depressions and/or apertures are provided along the inner surface of the ventilation insulating member, for example in the form of ribs, grooves, holes, corrugations and/or combinations thereof, so as to form a gap between the housing and the insulating ventilation member which allows air to escape therefrom. Advantageously, the protrusions, recesses and/or apertures are configured in one of a number of aspects, including but not limited to: a vertical alignment with respect to the housing, a horizontal alignment with respect to the housing, a tilt alignment with respect to the housing, and/or combinations thereof. Advantageously, the number of protrusions, recesses and/or apertures and their physical alignment are determined based on the amount of clamping to be applied to the housing, the configuration of the interrupter unit and ensuring effective removal of air by the ventilation insulating member.

These protrusions and depressions enable the ventilation insulation member to provide ventilation for the contact area(s). Advantageously, the venting characteristics of the insulating venting member allow it to be used in gas insulating applications. In gas-insulated applications, the vacuum interrupter unit is immersed and held under pressure in a container filled with an insulating gas. To fill the container with the insulating gas, the container is evacuated and air is evacuated from the container to create a vacuum, and finally the container is filled with the insulating gas. The venting characteristics of the insulating vent member prevent air from being trapped under the vent insulating member when air is drawn from the container. Moreover, the venting feature also allows the insulating vent member to maintain its position on the housing even when the air pressure changes during evacuation. Furthermore, the venting feature ensures that the air in the container is completely removed. Therefore, the ventilation insulation member is suitable for gas insulation applications with vacuum tubes used in gas containers of gas insulated switchgear.

A ventilation insulating member is flexibly disposed on the housing to accommodate one or more of the contact areas. Advantageously, the insulating ventilation member is configured as an annular member covering only the contact area(s). According to one aspect, the insulating ventilation member extends to cover more than one contact area. Advantageously, this aspect allows covering more than one contact area, and thus covering the solder edges that may form along the various contact areas of the ceramic and metal housings. Advantageously, the ventilation insulating member is made of an elastomeric material, such as silicone. According to one aspect, the insulating ventilation member is made of an elastomer only. According to another aspect, the insulating ventilation member is made of a composite material with an elastomer. According to yet another aspect, the insulating ventilation member is made of a graded material with an elastomer to cover one or more of the contact areas.

Further, a switching device is disclosed herein. The switching device is for example a circuit breaker arrangement. The circuit breaker arrangement comprises a pole module unit and a drive module unit operatively connected to the pole module unit. The pole module unit comprises the interrupter unit described above. The circuit breaker arrangement is a vacuum circuit breaker.

Furthermore, a switchgear arrangement is disclosed herein, comprising a cable compartment, a bus bar compartment and a switch compartment having the aforementioned circuit breaker arrangement comprising an interrupter unit. The switchgear arrangement is an air-insulated switchgear, a vacuum-insulated switchgear or a gas-insulated switchgear.

Drawings

The above and other features of the present invention will now be explained with reference to the drawings attached hereto. The illustrated embodiments are intended to illustrate, but not to limit the invention.

The invention will be further described with reference to exemplary embodiments shown in the drawings, in which:

fig. 1A shows a cross-sectional elevation view of a vacuum interrupter according to the prior art.

Fig. 1B shows a perspective view of a vacuum interrupter according to the prior art.

Fig. 2A illustrates a perspective view of a vacuum interrupter with vented insulation caps each covering a contact region in accordance with embodiments of the insulating vent member disclosed herein.

Figure 2B illustrates a perspective view of a vacuum interrupter having a vented insulation cap covering more than one contact area according to an embodiment of the insulating vent member disclosed herein.

Figure 3 illustrates a vent insulation cap according to embodiments of the insulating vent member disclosed herein.

Fig. 4 shows a circuit breaker arrangement with the vacuum interrupter shown in fig. 2A or 2B.

Fig. 5 shows a switchgear arrangement with the circuit breaker arrangement shown in fig. 4 comprising a vacuum interrupter.

Detailed Description

Various embodiments are described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident that such embodiment(s) may be practiced without these specific details.

Fig. 2A shows a perspective view of a vacuum interrupter 200 having vented insulation caps 201, the vented insulation caps 201 covering the contact area 105A shown in fig. 1B according to embodiments of the insulating vent member disclosed herein. The vented insulation cap 201 is flexibly positioned, i.e. spread and/or stretched over the ceramic housing 101A and positioned so as to cover the contact areas 105A, thereby preventing any influence of the solder edges (not shown) formed in these contact areas 105A.

Fig. 2B illustrates a perspective view of a vacuum interrupter 200 having a vented insulation cap 201, the vented insulation cap 201 covering more than one

contact area

105A and 105B shown in fig. 1B according to an embodiment of the insulating vent member disclosed herein. As shown in fig. 2B, the ventilation insulating cap 201 is configured to flexibly expand on the ceramic case 101A so as to cover the contact area 105A, and extends all the way along the ceramic case 101A up to the metal case 101B so as to cover the contact area 105B. This arrangement of the vented insulative caps provides additional coverage of the solder edges (not shown) formed in the

respective contact areas

105A and 105B.

Fig. 3 illustrates a venting insulator cap 201 in accordance with embodiments of the insulating venting member disclosed herein. The vented insulation cap 201 is a circular cap and/or sleeve configured to fit the vacuum interrupter 200 shown in fig. 2A and 2B. The vent insulator cap 201 is flexibly positioned on the ceramic housing 101A such that a bottom surface 201B of the vent insulator cap 201 is in direct physical contact with the

distal end

108A or 108B of the vacuum interrupter 200 shown in fig. 2A, and an inner surface 201C of the vent insulator cap 201 is disposed entirely against the contact region 105A and/or 105B and at least partially against the ceramic housing 101A. The vent insulator cap 201 includes a protrusion, i.e., rib 201A, that extends along the inner surface 201C up to the bottom surface 201B to allow a gap to be maintained throughout the height H of the vent insulator cap 201 to allow air to efficiently escape therefrom.

Fig. 4 shows a circuit breaker arrangement 400 with the vacuum interrupter 200 shown in fig. 2A or 2B. The circuit breaker arrangement 400 comprises a pole module unit 401 and a drive module unit 402, the drive module unit 402 being operatively connected to the pole module unit 401 via a pole insulator 403 and an insulating coupler 404. The pole module unit 401 includes the vacuum interrupter 200 described above. The circuit breaker arrangement 400 is a vacuum circuit breaker.

Fig. 5 shows a switchgear arrangement 500 having the circuit breaker arrangement 400 shown in fig. 4 including the vacuum interrupter 200. The switchgear arrangement 500 comprises a cable compartment 501, a switchgear compartment 502 and a bus bar compartment 503, all coupled to each other, the switchgear compartment 502 having the aforementioned circuit breaker arrangement 400 comprising the interrupter unit 200 shown in fig. 4.

While the invention has been described in detail with reference to certain embodiments, it should be understood that the invention is not limited to those embodiments. In view of the present disclosure, many modifications and variations may be apparent to those skilled in the art without departing from the scope of the various embodiments of the invention as described herein. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes, modifications and variations that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

1. Interrupter unit (200) comprising:

a housing (101), the housing (101) comprising a non-metallic housing (101A) and a metallic housing (101B), the non-metallic housing (101A) and the metallic housing (101B) being in contact with each other so as to form one or more contact areas (105A, 105B) therebetween;

the method is characterized in that:

a ventilation insulating member (201), the ventilation insulating member (201) being physically disposable on the housing (101) so as to accommodate at least one of the contact areas (105A, 105B).

2. Interrupter unit (200) according to claim 1, wherein the ventilation insulating member (201) comprises at least an elastomer.

3. Interrupter unit (200) according to any of claims 1 and 2, wherein the ventilation insulating member (201) is flexibly arranged on the housing (101) in order to accommodate one or more of the contact areas (105A, 105B).

4. The interrupter unit (200) of any of the preceding claims wherein the ventilation insulating member (201) comprises one or more of a protrusion (201A) and a recess (201A) along an inner surface (201C) of the ventilation insulating member (201).

5. Interrupter unit (200) according to any of the previous claims 1, 2 and 3, wherein the ventilation insulating member (201) comprises one or more apertures along an inner surface (201C) of the ventilation insulating member (201).

6. Interrupter unit (200) according to any of the preceding claims, being one of a vacuum interrupter unit and a gas interrupter unit.

7. A switching device (400) comprising at least:

a pole module unit (401), the pole module unit (401) comprising an interrupter unit (200) according to claims 1-6, and

a drive module unit (402), the drive module unit (402) being operatively connected to the pole module unit (401).

8. The switching device (400) of claim 7, being one of a vacuum circuit breaker and a gas circuit breaker.

9. A switchgear arrangement (500) comprising at least:

a cable chamber (501);

a switching chamber (502), the switching chamber (502) comprising a circuit breaker (400) according to claims 7-8, wherein the switching device (400) comprises an interrupter unit (201) according to claims 1-6; and

a bus bar compartment (503).

10. The switchgear arrangement (500) according to claim 9, being one of an air insulated switchgear, a vacuum insulated switchgear and a gas insulated switchgear.