top cover housing

Abstract

The present invention relates to a top cover housing (12) for a current transformer (10), which is to be mounted on top of an insulating post (16) of the current transformer and to form a chamber for a winding (14) of the current transformer (10), the top cover housing (12) being made of two parts (20) fixed to each other and including two openings (18) through which conductors penetrate the chamber, the openings (18) being symmetrically opposite about the main vertical axis (A) of the top cover housing (12), characterized in that the two parts (20) of the top cover housing (12) include two half-shells (20) comprising the same body (24).

Description

[0001] This application is a divisional application of the PCT patent application "Top Cover Housing" (application number: 201580078677.X, applicant: GE Technologies Inc.) which entered the Chinese national phase on October 9, 2017. Technical Field

[0002] This application relates to a top cover housing for a current transformer, which is designed to reduce the cost of manufacturing it.

[0003] More specifically, this application relates to a top cover housing made of two parts assembled together. Background Technology

[0004] Current transformers are widely used in metering and relay protection in the power industry, where they facilitate the safe measurement of large currents, often in the presence of high voltage. The rapid growth and high demand in power generation, transmission, and distribution systems are driving all manufacturers to design compact, optimal, and cost-effective power equipment, such as current transformers.

[0005] Typically, a top-core current transformer consists of a hollow tubular top cover supported by insulating posts, preferably fixed to a grounded base. The secondary winding is enclosed in a metal core housing, which is connected to ground via a centrally located metal tube passing through the hollow insulator. The metal core housing or primary conductor is insulated for this voltage level.

[0006] The top cover housing typically consists of two parts that are fixed together—a lower part and an upper part.

[0007] Typically, the lower component is larger and includes most of the components used to support the other parts of the current transformer. The smaller upper component is mainly used to hermetically seal the housing.

[0008] The two parts of the top cover shell are usually molded together. Therefore, the manufacture of the top cover shell requires two sets of molds.

[0009] The present invention aims to reduce costs and simplify the production of components for the top cover housing. Summary of the Invention

[0010] This invention relates to a top cover housing for a current transformer, which is to be mounted on top of the insulating pillars of the current transformer and forms a chamber for the windings of the current transformer.

[0011] The top cover housing is made of two components fixed to each other and includes two openings through which a conductor passes through the chamber. These openings are symmetrically opposite each other about the main vertical axis of the top cover housing.

[0012] The feature is that the two components of the top cover housing include two half-shells containing the same body.

[0013] The top cover housing, which includes two identical bodies and two components, reduces the number of different parts needed for assembly and the investment cost for manufacturing the parts.

[0014] Preferably, each component includes a base and a hollow body extending vertically from the base, the body including an end edge for contacting an end edge of the body of another component.

[0015] Preferably, the end edge is symmetrical along a horizontal axis perpendicular to the main vertical axis of the top cover housing.

[0016] Preferably, the end edge is positioned in a plane that is inclined relative to the horizontal plane.

[0017] Preferably, each component includes a flange extending radially from the end edge of the body about the main vertical axis of the top cover housing.

[0018] Preferably, the components are attached to each other at their respective flanges.

[0019] Preferably, each flange includes an annular groove for receiving a complementary gasket.

[0020] Preferably, the top cover housing includes an external connector attached to the flange.

[0021] Preferably, the body includes at least one wall, in which at least a portion of the opening is formed.

[0022] Preferably, the components are formed by molding. Attached Figure Description

[0023] The invention will be better understood and its further advantages and uses will become more apparent when considered in conjunction with the following detailed description of exemplary embodiments taken in conjunction with the accompanying drawings. In the drawings:

[0024] Figure 1 The display shows a current transformer including a top cover housing according to the present invention;

[0025] Figure 2 For those that are in the open state Figure 1 The image shows an enlarged view of the top cover casing. Detailed Implementation

[0026] Figure 1 The current transformer 10 is shown, which includes a top cover housing 12, which is a box enclosing multiple primary and secondary windings 14.

[0027] The top cover housing 12 is supported on top of the pillar 16 and includes two openings 18 through which the conductor 42 penetrates the interior of the top cover housing 12. Preferably, the openings 18 are symmetrically opposite each other about the main vertical axis A of the top cover housing 12. Molded aluminum.

[0028] The top cover housing 12 is made of two parts 20 that are fixed to each other by conventional means such as bolts, and the parts 20 form a chamber for receiving the winding 14.

[0029] Each component 20 includes a horizontal base 22 and a hollow body 24 extending vertically from the base 22 to define half of the chamber.

[0030] Preferably, the bodies 24 of the two components 20 are identical and comprise two half-shells. The components 20 of the top cover housing 12 are arranged symmetrically about a horizontal axis, and each component defines half of a chamber that receives the winding 14.

[0031] The base 22 includes a device that allows the associated component 20 to be fixed to the top of the post 16.

[0032] Since the bodies 24 of the two components 20 are identical, only the bases 22 of the components 20 may be identical or different, depending on the components to which they are fixed.

[0033] For example, here, the base 22 of the lower component 20 is fixed to the column 16, and the base 22 of the upper component 20 is connected to the expansion chamber (not shown). Therefore, the two bases 22 may be different.

[0034] According to one embodiment, the base 22 includes a hole 38 through which the post 16 passes or through the internal space of the top cover housing 12 and is connected to the expansion chamber.

[0035] The vertical end of the body 24 forms an edge 26, which is designed to contact the end edge 26 of the body 24 of another component.

[0036] Edge 26 is designed to provide an airtight seal when the two components 20 are fixed together. As explained earlier, the two components 20 are arranged symmetrically about a horizontal axis.

[0037] Therefore, each edge 26 is symmetrical about the same horizontal axis, such that two edges 26 can be matched and overlapped.

[0038] Here, each edge 26 is included in a plane including the horizontal axis, the plane being inclined relative to the horizontal plane.

[0039] It should be understood that the top cover housing is not limited to the edges 26 described above, as they can have any shape, as long as the shape of the edges 26 is symmetrical about the horizontal axis.

[0040] Furthermore, the general plane of edge 26 can be horizontal or inclined relative to the horizontal plane.

[0041] The two components 20 are fixed together by flanges 28 on each component 20, the flanges 28 extending radially outward from the edge 26 of the body about the main vertical axis A of the component 20.

[0042] The flanges 28 of the two components 20 face each other vertically and are in contact. They are fixed together, for example, by bolts. An annular gasket 30 is disposed between the two flanges to ensure the airtight seal of the chamber.

[0043] Preferably, each flange 28 includes a groove 40 for receiving the gasket 30.

[0044] When the two components 20 are made of metal (such as aluminum), they are electrically connected by an external U-shaped connector 32 that overlaps with the two flanges 28.

[0045] According to the embodiment shown in the accompanying drawings, and as previously mentioned, the generally flat plane of edge 26 is inclined relative to the horizontal plane. Based on this feature, the first wall 34 of the body 24 is long enough that the opening 18 can be arranged within this wall.

[0046] When the two components 20 are fixed together, the first wall 34, including the opening 18, is relative to the vertical main axis A of the top cover housing.

[0047] As explained above, the top cover housing 12, which includes two identical parts 20, requires only one set of molds to produce both parts 20.

[0048] This allows for a streamlined production process by reducing the number of casting components and logistics. It also reduces production costs.

[0049] Because there is no risk of inverting one component 20 to another, the assembly process is also simplified.

Claims

1. A top cover housing (12) for a current transformer (10), which is to be mounted on top of an insulating post (16) of the current transformer and forms a chamber for a winding (14) of the current transformer (10), wherein the winding (14) is enclosed in the housing, the housing being arranged in the chamber and connected to ground via a tube passing through the insulating post (16). The top cover housing (12) is made of two parts (20) fixed to each other and includes two openings (18), through which a conductor (42) penetrates the chamber. The openings (18) are symmetrically opposite each other about the main vertical axis (A) of the top cover housing (12), wherein the two openings are located on the side portion of one of the two parts. Its features are, The two components (20) of the top cover housing (12) are two half-shells containing the same body (24). Each component (20) includes an identical base (22) and a hollow body (24) extending vertically from the base (22), the body (24) including an end edge (26) that contacts the end edge (26) of the body (24) of another component (20). Each component (20) includes a flange (28) extending radially from the end edge (26) of the body (24) relative to the main vertical axis (A) of the top cover housing (12). The top cover housing (12) includes an external U-shaped connector (32) attached to the flange (28) and the external U-shaped connector covers the flange (28), wherein the two components (20) are made of metal and are electrically connected via the external U-shaped connector (32), and, The component includes two holes, a first hole located at the base of one component and a second hole located at the base of another component. In this configuration, one of the two components is formed as an upper component and the other as a lower component, wherein the base of the lower component is fixed to the insulating post, and wherein the insulating post passes through a hole in the base of the lower component.

2. The top cover shell (12) according to claim 1, characterized in that, The end edge (26) is symmetrical along the horizontal axis perpendicular to the main vertical axis (A) of the top cover shell (12).

3. The top cover shell (12) according to claim 1, characterized in that, The end edge (26) is positioned in a plane that is inclined relative to the horizontal plane.

4. The top cover shell (12) according to claim 1, characterized in that, The components (20) are attached to each other at their respective flanges (28).

5. The top cover housing (12) according to claim 1, characterized in that, Each flange (28) includes an annular groove (40) for receiving a complementary pad (30).

6. The top cover housing (12) according to claim 1, characterized in that, The body (24) includes at least one wall (34, 36) in which at least a portion of the opening (18) is formed.

7. The top cover housing (12) according to any one of the preceding claims, characterized in that, Each component (20) is formed by molding.

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