Flange material

Abstract

To provide a flange member that enables fixing an on-load tap changer, which conventionally required lifting, to a tank without the need for lifting.SOLUTION: The flange member that fixes an on-load tap changer to a tank accommodating a transformer body with insulation oil includes: an inner peripheral part to which the on-load tap changer is fixed; and an outer peripheral part fixed to an edge of an opening provided in an upper part of the tank. The on-load tap changer can be inserted into the tank through the opening while the on-load tap changer is fixed to the inner peripheral part, and the outer peripheral part can be fixed to the edge of the opening while the on-load tap changer is inserted into the tank through the opening.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a flange member for fixing an on-load tap changer to a tank that contains a transformer body together with insulating oil. [Background technology]

[0002] For example, as disclosed in Patent Document 1, in oil-filled static induction equipment such as oil-filled transformers for high-voltage power distribution equipment, the transformer body is housed in a tank together with insulating oil. In addition, in this type of oil-filled static induction equipment, the voltage applied to the transformer body when under load, i.e., during operation, is adjusted by appropriately switching connection points called taps using an on-load tap changer. This type of on-load tap changer is called, for example, an LTC (on-load tap changer). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-201100 A Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, an on-load tap changer is formed in a long cylindrical shape as a whole, and is inserted and fixed into the tank by lowering it from above while being suspended by a wire or the like through an opening provided in the top of the tank.

[0005] However, in recent years, new types of on-load tap changers have been provided that have a configuration comprising a main cylindrical portion that forms the main body and a sub-cylindrical portion that is smaller in diameter than the main cylindrical portion. To secure such new types of on-load tap changers in a tank, the head cover of the on-load tap changer is first removed, the on-load tap changer with the head cover removed is then placed in the tank through an opening in the tank, the head cover is then secured to the opening in the tank, and the on-load tap changer is then lifted from the tank through the opening in the tank and secured to the head cover.

[0006] Therefore, when a new on-load tap changer having a main cylindrical section and a sub-cylindrical section is fixed to a tank, the fixing work becomes extremely complicated. Furthermore, since the on-load tap changer is heavy and needs to be lifted, the lifted state tends to become unstable.

[0007] Therefore, the present invention provides a flange member that enables an on-load tap changer, which conventionally required lifting, to be fixed to a tank without the need for lifting. [Means for solving the problem]

[0008] The flange member of this embodiment is a flange member that fixes an on-load tap changer to a tank that accommodates the transformer body together with insulating oil, and has an inner circumferential portion to which the on-load tap changer is fixed, and an outer circumferential portion that is fixed to the end of an opening provided at the top of the tank, and is configured so that when the on-load tap changer is fixed to the inner circumferential portion, the on-load tap changer can be inserted into the tank through the opening, and is configured so that when the on-load tap changer is inserted into the tank through the opening, the outer circumferential portion can be fixed to the end of the opening. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a vertical cross-sectional view schematically illustrating an example of the configuration of a transformer according to an embodiment of the present invention. [Figure 2] 1 is a diagram illustrating an example of the configuration of a flange member according to an embodiment of the present invention; FIG. [Figure 3] FIG. 1 is a diagram illustrating a conventional fixing method for an on-load tap changer according to a comparative example of this embodiment. [Figure 4] FIG. 1 is a diagram illustrating an example of a method for fixing an on-load tap changer according to the present embodiment. [Figure 5] FIG. 10 is a diagram illustrating an example of a state during execution of circulation degassing according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment of a flange member will be described below with reference to the drawings. The oil-filled insulating transformer 1 illustrated in FIG. 1 is an example of an oil-filled stationary induction device. Hereinafter, the oil-filled insulating transformer 1 will be simply referred to as "transformer 1." The transformer 1 includes a metal tank 2 that is shaped like a horizontally long rectangular box overall. The tank 2 is configured by combining a tank main body 2A and a tank cover 2B. The tank main body 2A is formed in the shape of a long rectangular box with an open top. The tank main body 2A also includes an insulating oil inlet 2C. The tank cover 2B is formed in the shape of a long rectangular plate and closes the open top of the tank main body 2A.

[0011] The tank 2 accommodates a transformer body 3, which is an example of an induction device body. The tank 2 is filled with insulating oil M, such as mineral oil, for insulating and cooling purposes. The transformer body 3 is entirely immersed in the insulating oil M within the tank 2. The transformer body 3 has a well-known configuration and includes an iron core 3A and a coil 3B. The coil 3B is attached to the iron core 3A. The transformer body 3 is not located in the center of the tank 2, but rather at one end of the tank 2 in the longitudinal direction, in this case, at a position offset to the left side in FIG. 1.

[0012] Although detailed description is omitted, the transformer 1 may also include various auxiliary components. Examples of auxiliary components include various parts, devices, and equipment, such as bushings, conservators, radiators, relays, and pressure relief devices. The bushings are well-known components used for electrical connections. The conservators are well-known components that absorb the expansion and contraction of the insulating oil M due to temperature changes and prevent deterioration of the insulating oil M due to contact with the outside air. The radiators are well-known components that cool the transformer 1. The relays are well-known components that operate a circuit breaker (not shown) to stop the flow of current to the transformer body 3 based on the detected amount of decomposition gas generated from the insulating oil M. The pressure relief devices are well-known components that release decomposition gas generated from the insulating oil M and expanded insulating oil M to the outside. The transformer 1 may also include various other components that can be installed in this type of oil-filled static induction machine.

[0013] The transformer 1 also includes an on-load tap changer 11. The on-load tap changer 11 is a component that adjusts the voltage applied to the transformer body 3 when it is under load, i.e., when it is operating, by appropriately switching connection points (not shown), such as taps. Although not shown in detail, the on-load tap changer 11 is configured so that a tap selector, diverter switch, etc. are housed within a sealed body. The interior of the on-load tap changer 11 is also configured so that it is filled with insulating oil M.

[0014] The on-load tap changer 11 is configured by combining a long main cylindrical portion 11A, which forms the main body, with a long sub-cylindrical portion 11B, which has a smaller diameter than the main cylindrical portion 11A. Both the main cylindrical portion 11A and the sub-cylindrical portion 11B extend linearly in the vertical direction. The main cylindrical portion 11A and the sub-cylindrical portion 11B are combined in a parallel relationship. The longitudinal dimensions of the main cylindrical portion 11A and the sub-cylindrical portion 11B are approximately or exactly the same.

[0015] The on-load tap changer 11 is fixed to a tank cover 2B that forms the upper surface of the tank 2. That is, an opening 2D that penetrates the tank cover 2B in the thickness direction is provided in the portion of the tank cover 2B opposite to the transformer body 3. The on-load tap changer 11 is fixed to this opening 2D via a flange member 100. Next, a configuration example of this flange member 100 will be described in detail.

[0016] As illustrated in FIG. 2 , the flange member 100 has a main body formed by a flange main body 101 having a generally elliptical plate shape. The flange member 100 integrally includes an inner peripheral portion 102 and an outer peripheral portion 103. The flange main body 101 forms at least the space between the inner peripheral portion 102 and the outer peripheral portion 103. The inner peripheral portion 102 forms the inner edge of the flange main body 101. The outer peripheral portion 103 forms the outer edge of the flange member 101. The flange main body 101 is shaped so as to cover at least the upper portion of the sub-cylindrical portion 11B of the on-load tap changer 11.

[0017] The inner peripheral portion 102 is formed as a generally circular opening, and is provided at a position offset from the center of the flange main body 101. In this case, the inner peripheral portion 102 is provided at a position offset from the center of the flange main body 101 toward one end of the flange main body 101 in the longitudinal direction, i.e., an eccentric position. The outer peripheral portion 103 is provided along the outer edge of the flange main body 101. Therefore, the outer peripheral portion 103 is a generally elliptical ring-shaped component that follows the outer edge of the flange main body 101.

[0018] The inner periphery 102 has a plurality of threaded holes 102a formed along its circumferential direction. In this case, the plurality of threaded holes 102a are arranged at equal intervals along the circumferential direction of the inner periphery 102. An LTC flange 110, which will be described later, is fixed to the upper part of the inner periphery 102 with a plurality of screws (not shown). The upper end of the on-load tap changer 11 described above is fixed to the lower part of the LTC flange 110 with a plurality of screws (not shown). In this case, the upper end of the main cylindrical portion 11A of the on-load tap changer 11 is fixed to the lower part of the LTC flange 110. The upper end of the main cylindrical portion 11A of the on-load tap changer 11 is indirectly fixed to the inner periphery 102 of the flange member 100 via the LTC flange 110.

[0019] The outer periphery 103 has a plurality of screw holes 103a along its extension direction. In this case, the plurality of screw holes 103a are arranged at equal intervals along the extension direction of the outer periphery 103. This outer periphery 103 is fixed to the end of the opening 2D by a plurality of screws (not shown). In other words, the outer periphery 103 of the flange member 100 is directly fixed to the end of the opening 2D of the tank 2. The opening 2D is a roughly elliptical opening that is slightly smaller than the flange main body 101. However, the shape and size of the opening 2D can be appropriately changed as long as it is at least smaller than the flange main body 101.

[0020] The flange member 100 also has a vent 104 in a part of the flange main body 101. The vent 104 is configured to allow gases present in the tank 2, such as decomposition gases of the insulating oil M and residual gases generated during oil filling, to flow out.

[0021] 1, an LTC flange 110 is fixed to the upper part of the inner peripheral portion 102 of the flange member 100 by a plurality of screws (not shown). The LTC flange 110 includes a cylindrical LTC flange main body 110A and a plurality of pipe portions 110B. In this case, the LTC flange 110 includes three pipe portions 110B. Each of the plurality of pipe portions 110B is smoothly bent.

[0022] Next, an example of a method for fixing the on-load tap changer 11 to the tank 2 will be described in detail. That is, Fig. 3 illustrates a conventional method for fixing the on-load tap changer 11 to the tank 2. According to the conventional fixing method, first, in step A1, the head cover H attached to the upper end of the on-load tap changer 11 is removed, and then the on-load tap changer 11 from which the head cover H has been removed is placed in the tank 2 through the opening 2D of the tank 2. Note that a through hole Ha that penetrates the head cover H is provided in the center of the head cover H.

[0023] Then, in step A2, the head cover H is fixed to the upper part of the opening 2D of the tank 2. Then, in step A3, the on-load tap changer 11 inside the tank 2 is lifted up by a wire W through the opening 2D of the tank 2 and the through-hole Ha of the head cover H. Then, in step A4, the upper end of the on-load tap changer 11 lifted up by the wire W is fixed to the lower part of the head cover H with a plurality of screws (not shown).

[0024] As described above, conventionally, the on-load tap changer 11 has been mounted in the tank 2 using such a fixing method. However, this conventional fixing method makes the fixing work extremely complicated. Furthermore, since the on-load tap changer 11, which is a heavy object, needs to be lifted by the wire W, the lifted state tends to become unstable.

[0025] Therefore, in this embodiment, a fixing method utilizing the flange member 100 described above is adopted. That is, FIG. 4 shows an example of a fixing method for the on-load tap changer 11 according to this embodiment. According to the fixing method according to this embodiment, first, in step B1, the upper end of the on-load tap changer 11 is fixed to the lower part of the LTC flange 110 with a plurality of screws (not shown), thereby indirectly fixing the upper end of the on-load tap changer 11 to the inner peripheral portion 102 of the flange member 100 via the LTC flange 110. Then, in step B2, with the on-load tap changer 11 indirectly fixed to the inner peripheral portion 102 of the flange member 100 via the LTC flange 110, the on-load tap changer 11 is suspended by a wire W and inserted into the tank 2 through an opening 2D of the tank 2. Then, in step B3, with the on-load tap changer 11 inserted into the tank 2 through the opening 2D of the tank 2, the lower part of the outer periphery 103 of the flange member 100 is directly fixed to the upper part of the end of the opening 2D of the tank 2 using a plurality of screws not shown.

[0026] As described above, according to the fixing method of this embodiment, by utilizing the flange member 100 having the above-described configuration, the on-load tap changer 11 can be installed inside the tank 2 without the need to lift the on-load tap changer 11.

[0027] The flange member 100 according to the present embodiment exemplified above is configured so that, with the on-load tap changer 11 fixed to the inner circumferential portion 102, the on-load tap changer 11 can be inserted into the tank 2 through the opening 2D of the tank 2. Furthermore, with the on-load tap changer 11 inserted into the tank 2 through the opening 2D of the tank 2, the lower part of the outer circumferential portion 103 of the flange member 100 can be fixed to the upper part of the end of the opening 2D of the tank 2.

[0028] By utilizing the flange member 100 configured in this manner, the on-load tap changer 11, which conventionally required lifting, can be fixed inside the tank 2 without the need for lifting. Note that the on-load tap changer 11 may also be configured to be directly fixed to the inner periphery 102 of the flange member 100.

[0029] The on-load tap changer 11 is a new type of on-load tap changer that includes a main cylindrical portion 11A that forms the main body of the on-load tap changer, and a sub-cylindrical portion 11B that has a smaller diameter than the main cylindrical portion 11A. The flange main body 101, which is formed between the inner peripheral portion 102 and the outer peripheral portion 103 of the flange member 100, is shaped to cover the upper portion of the sub-cylindrical portion 11B, which is a portion of this new type of on-load tap changer 11 that is significantly different from conventional on-load tap changers. In other words, the flange member 100 according to this embodiment has a configuration that is fully compatible with the new type of on-load tap changer 11 that includes the main cylindrical portion 11A and the sub-cylindrical portion 11B, and in this case, has an eccentric configuration that is generally elliptical.

[0030] The flange member 100 also includes a vent 104 on the flange main body 101. The flange main body 101 of the flange member 100 is fixed so that its outer peripheral portion 103 overlaps the upper end of the opening 2D of the tank 2. As a result, a step is formed by the underside of the flange main body 101 and the inner peripheral surface of the opening 2D of the tank 2, and gases such as decomposition gases of the insulating oil M generated in the tank 2 and residual gases generated during oil filling and the like tend to accumulate in this step. The flange member 100 according to this embodiment allows such gases within the tank 2 to smoothly flow out through the vent 104. This makes it possible to prevent excessive accumulation of gases within the tank 2, such as decomposition gases of the insulating oil M and residual gases generated during oil filling and the like.

[0031] The above-described vent section 104 can also be used during circulatory degassing, in which insulating oil M in the tank 2 is degassed while being circulated. That is, as illustrated in FIG. 5 , circulatory degassing is performed by connecting a well-known circulatory degassing device 200 to the transformer 1. The circulatory degassing device 200 is connected to the vent section 104 of the flange member 100 and the insulating oil inlet 2C of the tank 2 via a circulation hose 201. When the circulatory degassing device 200 starts the circulatory degassing operation, it sucks the insulating oil M in the tank 2 through the vent section 104 and removes bubbles, impurities, and the like contained in the insulating oil M using a well-known remover. The circulatory degassing device 200 then returns the insulating oil M, from which bubbles and impurities have been removed, into the tank 2 through the insulating oil inlet 2C.

[0032] As described above, the circulation degassing device 200 degasses the insulating oil M while circulating the insulating oil M in the tank 2, and removes impurities contained in the insulating oil M. When the circulation degassing device 200 performs circulation degassing, the vent section 104 provided in the flange member 100 functions as a valve for causing the insulating oil M to flow out from the tank 2. Therefore, the transformer 1 can perform circulation degassing of the insulating oil M by utilizing the vent section 104 of the flange member 100, even if it does not have a valve for causing the insulating oil M to flow out from the tank 2, i.e., an insulating oil outlet.

[0033] This embodiment is not limited to the above-described embodiment, and various modifications and extensions can be made without departing from the spirit of the present invention. For example, the on-load tap changer is not limited to the on-load tap changer 11 having the main cylindrical portion 11A and the sub-cylindrical portion 11B described above, and on-load tap changers of various configurations can be applied. Furthermore, the shape and size of the flange main body 101 can be appropriately modified depending on the configuration and size of the on-load tap changer to be applied.

[0034] The position, shape, size, etc. of the inner peripheral portion 102 of the flange main body 101 can be appropriately changed depending on, for example, the configuration and size of the on-load tap changer to be applied, the shape and size of the flange member 100, etc. The position, shape, size, etc. of the vent portion 104 of the flange main body 101 can be appropriately changed depending on, for example, the shape and size of the flange member 100.

[0035] Furthermore, when painting the surface of the flange member 100, it is preferable not to paint the inner periphery 102 and the outer periphery 103, but to paint the parts of the flange main body 101 other than the inner periphery 102 and the outer periphery 103.

[0036] Although the embodiments of the present invention have been described above, these embodiments are presented merely as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, modifications, etc. can be made without departing from the spirit of the invention. The present embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions described in the claims and their equivalents. [Explanation of symbols]

[0037] In the drawing, 2 indicates the tank, 2D indicates the opening of the tank, 3 indicates the transformer body, 11 indicates the on-load tap changer, 11A indicates the main cylindrical portion, 11B indicates the sub-cylindrical portion, 100 indicates the flange member, 101 indicates the flange body portion, 102 indicates the inner peripheral portion, 103 indicates the outer peripheral portion, and 104 indicates the vent portion.

Claims

1. A flange member for fixing an on-load tap changer to a tank that accommodates a transformer body together with insulating oil, The on-load tap changer is fixed using a head cover that is fixed to an opening provided at the top of the tank and that requires lifting, an inner periphery to which the on-load tap changer is fixed; a peripheral portion fixed to an end of the opening; Equipped with the outer periphery includes a plurality of screw holes; a flange member configured so that the on-load tap changer can be inserted into the tank through the opening with the on-load tap changer fixed to the inner peripheral portion, and so that the outer peripheral portion can be fixed to the end of the opening with a plurality of screws with the on-load tap changer inserted into the tank through the opening.

2. The on-load tap changer includes a main cylindrical portion constituting a main body thereof, and a sub-cylindrical portion having a diameter smaller than that of the main cylindrical portion, 2. The flange member according to claim 1, wherein the flange body portion formed between the inner peripheral portion and the outer peripheral portion is shaped to cover an upper portion of the sub-cylindrical portion of the on-load tap changer.

3. 3. The flange member according to claim 2, wherein the flange body portion is provided with a vent portion for allowing gas within the tank to flow out.

4. 4. The flange member according to claim 3, wherein the vent portion functions as a valve for discharging insulating oil from the tank during circulation degassing, in which insulating oil is circulated in the tank while being degassed.

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