Bar-shaped off-circuit tap switch with shielding cover

Abstract

The utility model provides a bar-shaped off-circuit tap-changer with a shielding case, which comprises an operating mechanism, a moving contact group, a support plate, a support seat, a transmission mechanism, a static contact group and an insulating plate, the operating mechanism is fixed at the top of a transformer box cover, the bottom of the operating mechanism penetrates through the transformer box cover to be connected with one end of a coupler, and the other end of the coupler is connected with the transmission mechanism. The transmission mechanism is arranged on the supporting seat and is in configuration connection with the supporting plate, the moving contact groups are arranged on the supporting plate at intervals, the static contact groups are arranged on the insulating plate at intervals, the insulating plate is fixedly arranged on the transformer box cover through the fixing plate, the insulating plate is connected with the supporting seat, and the shielding covers symmetrically cover the outer sides of working areas where the static contact groups are in contact with the moving contact groups. According to the utility model, the electrodes of various shapes of the moving contact group are isolated in the shielding cover, so that the insulation performance of the tap switch on a transformer coil and a box body is enhanced, and meanwhile, the volume of a transformer is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of transformer tap changers, and in particular to a strip-shaped de-excitation tap changer with a shielding cover. Background Art

[0002] Off-circuit tap changers are used to adjust the output voltage of power transformers. There are many types of off-circuit tap changers available on the market, including strip, drum, cage and cylinder. Among them, strip off-circuit tap changers are widely used due to their relatively small size.

[0003] For example, the Chinese Patent Office announced that Chinese patent CN 105938764 A involves a strip-type off-excitation tap-changer, whose conductor consists of a moving contact assembly and a stationary contact, and the moving contact assembly is provided with a sheet-shaped clip-type moving contact and a spring and a contact bracket, and the stationary contact is cylindrical or flat cylindrical. Since these parts are sheet-shaped or small in size, there are many sharp and small-rounded electrodes (small rounded corners are also equivalent to sharp corners under high voltage), which will cause the switch electrode to discharge at the tip between the external transformer coil and the box under high voltage. Therefore, the strip-type off-excitation tap-changer is mainly used in 10kV distribution transformers with low voltage levels. For transformers with higher voltage levels such as 35kV and above, other forms of off-excitation tap-changers with better electrode shapes are generally selected, such as drum switches, but drum switches are larger in size and have high manufacturing costs. Summary of the invention

[0004] The technical problem to be solved by the utility model is to provide a strip-shaped de-excitation tap changer with a shielding cover for the above-mentioned problems, which can effectively shield the transformer coil and the box body, and at the same time is conducive to the miniaturization of the transformer, with significant material saving benefits.

[0005] The embodiment of the present application is implemented as follows:

[0006] An embodiment of the present application provides a strip-shaped de-excitation tap changer with a shielding cover, comprising an operating mechanism, a moving contact group, a support plate, a support seat, a transmission mechanism, a stationary contact group and an insulating plate, wherein the operating mechanism is fixed to the top of a transformer box cover, and the bottom passes through the transformer box cover and is connected to one end of a coupling, and the other end of the coupling is connected to the transmission mechanism, the transmission mechanism is arranged on the support seat and is connected to the support plate, the moving contact groups are arranged on the support plate at intervals, the stationary contact groups are arranged on the insulating plate at intervals, the insulating plate is fixed to the transformer box cover through a fixing plate, and the insulating plate is connected to the support seat, and is characterized in that the outer side of the working area where the stationary contact group contacts the moving contact group is symmetrically covered with a shielding cover.

[0007] In some optional implementation schemes, the shielding cover is symmetrically arranged outside the moving contact group, moves with the moving contact group, and the shielding cover completely covers the moving contact group.

[0008] In some optional implementation schemes, the shielding cover is symmetrically arranged on both sides of the insulating plate, does not move with the moving contact group, and completely covers the moving contact group and partially or completely covers the stationary contact group.

[0009] In some optional implementation schemes, the shielding cover is provided with a connecting hole, which is connected to the moving contact or the insulating plate via connecting screws, and the moving contact and the insulating plate are provided with corresponding connecting screw holes.

[0010] In some optional embodiments, an axial through hole is provided on the insulating plate inwardly along the connecting screw hole, an equipotential connector is provided in the through hole, and two end ends of the equipotential connector are respectively in contact with the connecting screw and the static contact.

[0011] In some optional embodiments, the shielding cover is a circular disk structure or a square disk structure, and is a block structure with an arc-shaped convex ring along the edge to form a concave end surface, and the connecting hole is provided on the concave end surface.

[0012] In some optional embodiments, the shielding cover is a circular disk structure or a square disk structure, an inner groove is provided at the connection, and the connection hole is provided in the inner groove.

[0013] In some optional embodiments, the shielding cover is connected to a static contact in the corresponding static contact group at the same potential through the equipotential connector.

[0014] In some optional embodiments, the shielding cover is made of a conductive material.

[0015] In some optional embodiments, a gasket is provided at the connection between the shielding cover and the moving contact or the insulating plate.

[0016] The beneficial effects of the present application are as follows: a strip-shaped non-excitation tap changer with a shielding cover provided by the present application has a shielding cover symmetrically covered on the upper and lower working areas where the static contact group and the moving contact group are in contact, and electrodes of various shapes of the moving contact group can be isolated in the shielding cover. At this time, the static contact group or the moving contact group of the tap changer is an integral large electrode to the outside, so that it can effectively shield the transformer coil and the box body, greatly reduce the electric field strength, reduce the local discharge, and enhance the insulation performance of the tap changer to the transformer coil and the box body. It can be suitable for power transformers with higher voltage levels, such as switches for new energy 35kV, 66kV wind power and photovoltaic transformers; at the same time, the insulation distance between the tap changer and the transformer coil and the box body can be shortened, which is conducive to the miniaturization of the transformer and has significant material saving benefits. At the same time, the miniaturization of the transformer volume is of great significance to wind power towers and cabin transformers. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is a front view of an embodiment of the present application;

[0019] Figure 2 for Figure 1 AA view;

[0020] Figure 3 for Figure 2 BB direction view;

[0021] Figure 4 for Figure 2 CC view;

[0022] Figure 5 A front view of another embodiment of the present application;

[0023] Figure 6 for Figure 5 AA view;

[0024] Figure 7 for Figure 6 BB direction view;

[0025] Figure 8 for Figure 6 CC view;

[0026] Fig. 9 A front view of a shielding cover according to an embodiment of the present application;

[0027] Fig.10 This is a front view of a shielding cover according to another embodiment of the present application. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0030] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0031] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0032] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0033] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0034] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0035] The features and performance of the present application are further described in detail below in conjunction with the embodiments.

[0036] like Figure 1 As shown, the utility model provides a strip-shaped de-excitation tap changer with a shielding cover, comprising an operating mechanism 1, a moving contact group 2, a support plate 3, a support seat 4, a transmission mechanism, a static contact group 5 and an insulating plate 6. The operating mechanism is fixed to the top of a transformer box cover 7, and the bottom passes through the transformer box cover and is connected to one end of a coupling 8, and the other end of the coupling is connected to the transmission mechanism. The transmission mechanism is arranged on the support seat, and the support seat is configured and connected to the support plate. The moving contact groups are arranged on the support plate at intervals, and the static contact groups are arranged on the insulating plate at intervals. The insulating plate is fixed on the transformer box cover through a fixing plate 9, and the insulating plate is connected to the support seat. The working area where the static contact group and the moving contact group contact and shift is symmetrically covered with a shielding cover 10 above and below.

[0037] Setting up a shielding cover can isolate electrodes of various shapes of the moving contact group inside the shielding cover. At this time, the static contact group or the moving contact group of the tap changer is an integral large electrode to the outside, which can effectively shield the transformer coil and the box, greatly reduce the electric field strength, reduce the amount of local discharge, and enhance the insulation performance of the tap changer to the transformer coil and the box. At the same time, the insulation distance between the tap changer and the transformer coil and the box can be shortened, which is conducive to the miniaturization of the transformer and has significant material saving benefits.

[0038] Example 1

[0039] like Figure 2-Figure 4 As shown, in this embodiment, the shielding cover is symmetrically arranged on the outside of the moving contact group. When the tap switch is shifted, the shielding cover moves with the moving contact group.

[0040] At this time, the shielding cover is fixed on the moving contact group, completely covering the entire moving contact group, and shielding the entire moving contact group.

[0041] Example 2

[0042] like Figure 5-Figure 8As shown, in this embodiment, the shielding cover is symmetrically arranged on both sides of the insulating plate. When the tap switch is shifted, the shielding cover does not move with the moving contact group.

[0043] In this embodiment, the shielding cover not only covers the moving contact group, but also covers part or all of the stationary contact group, thereby shielding the moving contact group and the stationary contact group.

[0044] In the above two embodiments, the shielding cover is provided with connecting holes, which are connected to the moving contact or the insulating plate through connecting screws 11, and the moving contact and the insulating plate are provided with connecting screw holes correspondingly.

[0045] When the shielding cover is connected to the insulating plate, an axial through hole is provided inwardly along the connecting screw hole on the insulating plate, and an equipotential connector 12 is provided in the through hole. The two ends of the equipotential connector are respectively in contact with the connecting screw and the static contact to avoid floating potential, so that the shielding cover and the static contact have the same potential.

[0046] In some optional embodiments, the connection of the shielding cover is provided with an inner groove 13, and the connection hole is provided in the inner groove (see Fig. 9 The shielding cover can be a circular disk structure or a square disk structure. In some optional embodiments, an arc-shaped convex ring 14 is provided along the edge of the disk body to form a block structure with a concave end surface, and the connection hole is provided on the concave end surface (see Fig.10 ). The heads of the connecting screws will not exceed the highest point of the shielding cover and will not form protruding ends on the surface.

[0047] In some optional embodiments, the shielding cover is connected to one of the static contacts in the corresponding static contact group at the same potential through an equipotential connector.

[0048] The shield is made of conductive material.

[0049] In some optional embodiments, a spacer 15 may be provided at the connection between the shielding cover and the moving contact or the insulating plate.

[0050] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

Claims

1. A strip-shaped off-excitation tap changer with a shield, comprising an operating mechanism, a moving contact group, a support plate, a support seat, a transmission mechanism, a static contact group and an insulating plate, wherein the operating mechanism is fixed to the top of the transformer box cover, the bottom passes through the transformer box cover and is connected to one end of the coupling, the other end of the coupling is connected to the transmission mechanism, the transmission mechanism is arranged on the support seat, and is connected to the support plate, the moving contact group is arranged on the support plate at intervals, the static contact group is arranged on the insulating plate at intervals, the insulating plate is fixed to the transformer box cover through a fixing plate, and the insulating plate is connected to the support seat, characterized in that: The outer side of the working area where the static contact group contacts the moving contact group is symmetrically covered with a shielding cover.

2. A strip-shaped off-circuit tap changer with a shielding cover according to claim 1, characterized in that: The shielding cover is symmetrically arranged outside the moving contact group and moves with the moving contact group. The shielding cover completely covers the moving contact group.

3. The strip-shaped off-circuit tap changer with a shielding cover according to claim 1, characterized in that: The shielding cover is symmetrically arranged on both sides of the insulating plate and does not move with the moving contact group. The shielding cover completely covers the moving contact group and partially or completely covers the stationary contact group.

4. A strip-shaped off-circuit tap changer with a shielding cover according to claim 2 or 3, characterized in that: The shielding cover is provided with a connecting hole, which is connected to the moving contact or the insulating plate through connecting screws, and the moving contact and the insulating plate are correspondingly provided with connecting screw holes.

5. A strip-shaped off-circuit tap changer with a shielding cover according to claim 4, characterized in that: An axial through hole is provided on the insulating plate inwardly along the connecting screw hole, and an equipotential connector is provided in the through hole. Two ends of the equipotential connector are respectively in contact with the connecting screw and the static contact.

6. A strip-shaped off-circuit tap changer with a shielding cover according to claim 5, characterized in that: The shielding cover is a circular disk structure or a square disk structure, and is provided with an arc-shaped convex ring along the edge to form a block structure with a concave end surface, and the connecting hole is provided on the concave end surface.

7. The strip-shaped off-circuit tap changer with a shielding cover according to claim 5, characterized in that: The shielding cover is a circular disk structure or a square disk structure, an inner groove is provided at the connection, and the connection hole is provided in the inner groove.

8. A strip-shaped off-circuit tap changer with a shielding cover according to claim 6 or 7, characterized in that: The shielding cover is connected to a static contact in the corresponding static contact group at the same potential through the equipotential connector.

9. The strip-shaped off-circuit tap changer with a shielding cover according to claim 8, characterized in that: The shielding cover is made of conductive material.

10. The strip-shaped off-circuit tap changer with a shielding cover according to claim 9, characterized in that: A cushion block is provided at the connection between the shielding cover and the moving contact or the insulating plate.

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