Transformer replacement method

Abstract

To provide a transformer replacement method that enables a transformer installed in the premises of a substation or the like to be replaced in a short period of time.SOLUTION: A transformer replacement method for replacing a transformer installed in premises adjacent to a transformer retaining structure includes the steps of installing a new second transformer in an empty space in the premises adjacent to a first transformer to be replaced and adjacent to the transformer retaining structure, where foundation work has been done, performing specified modification work for installing the second transformer on the transformer retaining structure and making a mold for installing a lead wire from the main circuit arranged on the transformer retaining structure, connecting the lead wire to the second transformer according to the mold for the lead wire, and disconnecting the first transformer from the main circuit and removing the first transformer.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a transformer replacement method for replacing a transformer installed on the premises of a substation or the like. [Background technology]

[0002] Transformers installed in primary substations and the like are devices that transform AC power. These transformers are several meters to several tens of meters in size and are usually installed on foundations that have been constructed within the premises of a substation or other facility.

[0003] When a transformer needs to be replaced due to breakdown or aging, a period of time must be secured for the work to be done and the transformer must be shut down for that period. However, if it is difficult to secure such a shutdown period, the current practice is to carry out foundation work in a new space on the premises, install a new transformer, and then remove the old transformer.

[0004] As a technique for replacing equipment and the like in such facilities, a construction method that enables equipment (switchgear) replacement without installing a new foundation is known (see, for example, Patent Document 1). The switchgear replacement method described in Patent Document 1 involves installing a secondary distribution box and an in-house GPT of a new switchgear in the remaining space of the foundation, connecting them to a transformer in parallel with the existing switchgear, removing the distribution line box and the like of the existing switchgear from the foundation, installing the distribution line box and the like of the new switchgear on the foundation and connecting it to the transformer, and removing the secondary distribution box and the in-house GPT box of the existing switchgear from the foundation. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-097482 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when replacing the transformer itself, the switchgear replacement method described in Patent Document 1 cannot be applied, and there has been a demand for a method that enables the transformer to be replaced in a short period of time.

[0007] Therefore, an object of the present invention is to provide a transformer replacement method that enables a transformer to be replaced in a short period of time. [Means for solving the problem]

[0008] In order to solve the above problem, the invention of claim 1 is a transformer replacement method in which a transformer terminal steel structure is installed and a transformer installed within a premises adjacent to the transformer terminal steel structure is replaced, characterized by performing the following steps: installing a new second transformer in an empty space near the first transformer to be replaced within the premises and near the transformer terminal steel structure, where foundation work has been done; performing specified modification work on the transformer terminal steel structure to install the second transformer, and making a mold for installing lead wires from the main circuit installed in the transformer terminal steel structure; connecting the lead wires to the second transformer according to the molded lead wires; and disconnecting the first transformer from the main circuit and removing the first transformer.

[0009] The invention of claim 2 is characterized in that in the step of installing the second transformer in the transformer replacement method described in claim 1, the second transformer is installed at a position adjacent to the transformer retaining steel structure so as to face the first transformer adjacent to the transformer retaining steel structure.

[0010] The invention of claim 3 is characterized in that in the step of performing specified modification work on the transformer retention steel structure in the transformer replacement method described in claim 1, the insulators installed on the transformer retention steel structure are changed to correspond to the second transformer.

[0011] The invention of claim 4 is characterized in that, in the transformer replacement method described in any one of claims 1 to 3, in a process prior to the step of installing the second transformer, a step is carried out in which equipment that has been installed on the secondary side of the first transformer and whose foundation work has been completed is relocated to secure the free space.

[0012] The invention of claim 5 is characterized in that in the step of relocating the equipment in the transformer replacement method described in claim 4, the equipment includes either a shunt reactor or a neutral point reactor or both installed within the premises. [Effects of the Invention]

[0013] According to the invention described in claim 1, a new second transformer is installed in an empty space near the first transformer to be replaced and near the transformer dead-end steel structure, where foundation work has been completed. The required modifications are then made to the transformer dead-end steel structure, a mold is made for installing lead wires from the main circuit, the lead wires are connected to the second transformer, and the first transformer is removed. This allows the existing circuit breakers, disconnecting switches, busbar steel structure, etc., to be reused within the premises. This makes it possible to replace the transformer in a short period of time.

[0014] According to the invention described in claim 2, the second transformer is installed adjacent to the transformer dead-end steel structure so as to face the first transformer adjacent to the transformer dead-end steel structure. This allows replacement work to be carried out near the existing transformer, making it possible to replace the transformer in a short period of time.

[0015] According to the invention described in claim 3, the insulators installed on the transformer dead-end steel structure are changed to accommodate the second transformer. This allows the work to be carried out in parallel with other process work, making it possible to replace the transformer in a short period of time.

[0016] According to the inventions of claims 4 and 5, the equipment installed on the secondary side of the first transformer with its foundation laid, specifically the shunt reactor or neutral reactor, can be relocated to free up space. This allows the existing circuit breakers, disconnecting switches, busbar steel structures, etc. to be reused within the premises. This makes it possible to replace the transformer in a short period of time. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a plan view of a premises showing an example of a premises 1 in which a transformer 10 is installed, the transformer replacement method being carried out according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a side view showing the premises 1 of FIG. [Figure 3] 3 is a flowchart showing a transformer replacement method according to the first embodiment of the present invention. [Figure 4] 2 is a plan view showing a state in which a shunt reactor 40 and a neutral point reactor 50 have been moved from the state shown in FIG. 1. FIG. [Figure 5] 5 is a plan view showing a state in which a new transformer 60 has been installed, following the state shown in FIG. 4. FIG. [Figure 6] FIG. 5 is a side view showing the premises 1 of FIG. 4. [Figure 7] FIG. 6 is a plan view showing a state in which the transformer 10 has been removed from the state shown in FIG. 5. [Figure 8] FIG. 8 is a side view showing the premises 1 of FIG. 7. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention will be described below based on the illustrated embodiments.

[0019] (overview) The transformer replacement method according to an embodiment of the present invention is a method for replacing a transformer installed in a primary substation, etc. This transformer replacement method is a method that makes it possible to shorten the continuous shutdown period of a transformer when replacing it due to a transformer failure or aging, even when it is difficult to shut down the transformer for a long period of time.

[0020] Fig. 1 is a plan view of an example of a premises 1 in which a transformer 10 is installed, on which a transformer replacement method according to a first embodiment of the present invention is to be carried out. Fig. 2 is a side view of the premises 1 of Fig. 1.

[0021] The premises 1 shown in Figure 1 is a plan view showing an excerpt from the premises of a facility such as a primary substation. The substation, which is an example of premises 1, is a primary substation that converts the voltage of electricity in a power system and controls the flow of power by connecting and opening / closing each power system. Such substations also reduce the voltage of electricity transmitted from power plants and transmit it to large factories and other facilities. Such substations are also facilities that send electricity to secondary substations, where it is further reduced in voltage and transmitted to small and medium-sized factories and other facilities.

[0022] As shown in FIGS. 1 and 2, a premises 1 is equipped with a transformer 10, a transformer dead-end steel structure 20, multiple high-voltage lines (main circuits) (high-voltage lines 31, 32, and 33 are shown in FIG. 1; hereinafter, these may be collectively referred to as "high-voltage lines 30"), a shunt reactor 40, and a neutral reactor 50. The transformer 10 is a facility that transforms (e.g., from 110,000 V to 66,000 V) the voltage transmitted from a power plant, which is an example of the premises 1. The transformer dead-end steel structure 20 is a gate-like facility (shown as a tower in FIG. 2, but actually extends in the depth direction) for supporting the high-voltage line 30, and is typically a steel structure several tens of meters long. The high-voltage line 30 is a transmission line that transmits high-voltage power (e.g., 6,600 V power) output from a substation. The shunt reactor (ShR) 40 is connected to the shunt of the AC circuit and is a device that compensates for the leading reactive power by supplying lagging reactive power of the high-voltage line 30. The neutral point reactor (NGL) 50 is connected to the neutral point of the power system and is a device that prevents an abnormal rise in voltage to ground in the event of a ground fault in the power system and also compensates for the system's capacitance to ground.

[0023] 1 and 2, the transformer 10 is installed adjacent to the transformer dead-end steel structure 20, and a lead wire branching from the high-voltage line 30 is connected to it. The shunt reactor 40 and the neutral point reactor 50 are installed adjacent to the transformer dead-end steel structure 20, facing the transformer 10, on the secondary side of the transformer 10. As shown in FIG. 2, the high-voltage line 30 passes above the transformer 10, the shunt reactor 40, and the neutral point reactor 50, and is installed while being supported by the transformer dead-end steel structure 20.

[0024] Within the premises 1, the transformer 10, transformer dead-end steel structure 20, shunt reactor 40, and neutral reactor 50 are installed on the ground on which foundation work has been performed. Here, foundation work refers to excavating the ground to perform earthing work, installing cable pits, etc., and pouring concrete to prepare the ground for the installation of various devices such as the transformer 10.

[0025] The transformer replacement method according to the first embodiment is a method for replacing transformer 10, but if there is no available space near transformer 10 to install a new replacement transformer, it must be installed at a location away from transformer 10. This requires the installation of new circuit breakers, disconnecting switches, busbar steel structures, etc., and also the construction of foundations if they have not been done at the locations where these devices will be installed, so it is necessary to secure a long construction period.

[0026] Furthermore, for example, when replacing a transformer at a distribution substation, it is possible to shut down the transformer to be replaced for an extended period of time by temporarily installing a portable transformer. However, in the case of transformers at primary substations, their capacity is large, so this cannot be achieved by installing a temporary portable transformer.

[0027] Therefore, in this embodiment, the shunt reactor 40 and the neutral point reactor 50 are relocated, and a new transformer is installed in the space thus freed up, thereby making effective use of existing facilities, making it possible to replace the transformer in a short period of time and shortening the period of continuous shutdown of the transformer.

[0028] In this embodiment, the shunt reactor 40 and the neutral point reactor 50 are shown as examples of equipment to be relocated, but the equipment is not limited to these and may be any other equipment that can be relocated within the premises 1.

[0029] (Embodiment 1) <Process flow> 3 to 8 show this embodiment, and Fig. 3 is a flowchart showing the transformer replacement method according to embodiment 1 of the present invention. An example of the flow of the transformer replacement method according to embodiment 1 of the present invention will be described with reference to Figs. 3 to 8.

[0030] In step S101, the shunt reactor 40 and the neutral reactor 50 are relocated from their current positions facing the transformer (first transformer) 10. The shunt reactor 40 and the neutral reactor 50 may be relocated to any position that allows the respective devices to function properly, and it is desirable that the relocation positions are not far from the current positions in view of the wiring and other conditions.

[0031] Fig. 4 is a plan view showing a state in which the shunt reactor 40 and the neutral reactor 50 have been relocated from the state shown in Fig. 1. As shown in Fig. 4, in the process of step S101, the shunt reactor 40 and the neutral reactor 50 are relocated to a position that does not face the transformer 10. This position is close to the original installation positions of the shunt reactor 40 and the neutral reactor 50 and is therefore a desirable position because it facilitates wiring work.

[0032] If foundation work has not been carried out at the new location of the shunt reactor 40 and the neutral point reactor 50, foundation work is also carried out to relocate them to that location. However, even if foundation work has been carried out in advance, improvement work will be required to install the shunt reactor 40 and the neutral point reactor 50. Furthermore, in the process of step S101, wiring work is also carried out, but if existing circuit breakers and disconnecting switches can be used, they may be used.

[0033] In the process of step S102, a new transformer (second transformer) 60 is installed in the premises 1. The transformer 60 is a transformer that replaces the current transformer 10, and is a device that has the same functions as the transformer 10. The location where the transformer 60 is installed is, for example, the location where the shunt reactor 40 and the neutral point reactor 50 were installed, in the vacant space that has been secured by relocating the shunt reactor 40 and the neutral point reactor 50.

[0034] Fig. 5 is a plan view showing a state in which a new transformer 60 has been installed, following the state shown in Fig. 4. As shown in Fig. 5, in the process of step S102, the transformer 60 is moved to a position opposite the transformer 10, where the shunt reactor 40 and the neutral point reactor 50 were originally installed. This position is near the transformer 10 and near the transformer dead-end steel structure 20, specifically, a position adjacent to the transformer dead-end steel structure 20 and opposite the transformer 10, which is a desirable position for connecting lead wires to the high-voltage line 30.

[0035] In this embodiment, the shunt reactor 40 and the neutral point reactor 50 are relocated and the transformer 60 is installed in that position, but if there is vacant space in a similar position, the transformer 60 may be installed without relocating the equipment.

[0036] In the process of step S103, predetermined modifications are made to the transformer dead-end steel structure 20. Specifically, modifications to the transformer dead-end steel structure 20 refer to, for example, work to change the insulators installed in the transformer dead-end steel structure 20 to make them compatible with the transformer 60, but are not limited to such work and refer to general renovation work to make the transformer 60 compatible.

[0037] Fig. 6 is a side view showing the premises 1 of Fig. 4. As shown in Fig. 6, in the process of step S103, the insulators 70 installed on the transformer dead-end steel structure 20 are changed to insulators for 110 kV, for example, to correspond to the transformer 60. The process of step S103 may be performed in parallel with the process of step S102.

[0038] In the process of step S104, a mold is taken for connecting and installing the lead wire from the high-voltage line 30 to the transformer 60. As shown in Fig. 6, in the process of step S104, a mold is taken for installing the lead wire 80 that is drawn in from the high-voltage line 30. The process of step S104 may be performed in parallel with the processes of steps S102 and S103.

[0039] In step S105, lead wires 80 from the high-voltage line 30 are connected to the transformer 60. In step S105, the lead wires 80 drawn from the high-voltage line 30 are connected to the transformer 60 in accordance with the pattern formed in step S104. Step S105 may be performed in parallel with steps S102 and S103.

[0040] In step S106, the transformer 10 to be replaced is removed. At this time, work is performed to disconnect the transformer 10 from the lead wire 80. Note that step S106 is performed simultaneously with step S105, but is separated into separate steps for the sake of explanation.

[0041] Fig. 7 is a plan view showing a state in which transformer 10 has been removed from the state shown in Fig. 5. Fig. 8 is a side view showing the premises 1 of Fig. 7. As shown in Figs. 7 and 8, in the process of step S106, transformer 10 shown in Figs. 5 and 6 is removed.

[0042] <Effects> According to the transformer replacement method of the first embodiment, a new transformer (second transformer) 60 is installed in an empty space near the transformer (first transformer) 10 to be replaced and near the transformer dead-end steel structure 20, where the foundation work has been completed (the position where the shunt reactor 40 and the neutral point reactor 50 were located before being relocated). The transformer dead-end steel structure 20 is modified as required, a mold is made for installing lead wires from the high-voltage line (main circuit) 30, the lead wires are connected to the transformer 60, and the transformer 10 is removed. This allows the use of circuit breakers, disconnecting switches, busbar steel structures, and the like already installed in the premises 1. This makes it possible to replace the transformer 10 with the transformer 60 in a short period of time.

[0043] In addition, the transformer 60 is installed adjacent to the transformer dead-end steel structure 20 so as to face the transformer 10 adjacent to the transformer dead-end steel structure 20. This allows replacement work to be carried out near the existing transformer 10, making it possible to replace the transformer in a short period of time.

[0044] Additionally, the insulators 70 installed on the transformer dead-end steel structure 20 are changed to accommodate the transformer 60. This allows the work to be carried out in parallel with other process work, for example, the installation process of the transformer 60, making it possible to replace the transformer in a short period of time.

[0045] Furthermore, the shunt reactor 40 and neutral reactor 50 (either one or both) that are installed on the secondary side of the transformer 10 after foundation work has been completed are relocated to secure free space. This allows the existing circuit breakers, disconnecting switches, busbar steel structures, etc., to be reused within the premises 1. This makes it possible to replace the transformer in a short period of time.

[0046] Although the embodiments of the present invention have been described in detail above, the specific configuration is not limited to these embodiments, and even if there are design changes within the scope of the present invention that do not deviate from the gist of the present invention, they are still included in the present invention. [Explanation of symbols]

[0047] 1: Inside the premises 10: Transformer 20: Transformer dead-end steel structure 30: High voltage line 31: High voltage line 32: High voltage line 33: High voltage line 40: Shunt reactor 50: Neutral reactor 60: Transformer 70: Insulator 80: Lead wire

Claims

1. A transformer replacement method in which a transformer dead-end steel structure is installed and a transformer installed in a premises adjacent to the transformer dead-end steel structure is replaced, installing a new second transformer in an empty space in the vicinity of the first transformer to be replaced and in the vicinity of the transformer dead-end steel structure within the premises, where foundation work has been completed; performing predetermined modification work on the transformer dead-end ironwork to install the second transformer, and taking a mold for installing lead wires from a main circuit arranged on the transformer dead-end ironwork; connecting the leads to the second transformer along the lead pattern; disconnecting the first transformer from the main circuit and removing the first transformer; A transformer replacement method comprising the steps of:

2. In the step of installing the second transformer, the second transformer is installed at a position adjacent to the transformer dead-end ironwork so as to face the first transformer adjacent to the transformer dead-end ironwork.

2. The transformer replacement method according to claim 1 .

3. In the step of carrying out predetermined modification work on the transformer dead-end steel structure, insulators installed on the transformer dead-end steel structure are changed to correspond to the second transformer.

2. The transformer replacement method according to claim 1 .

4. In a process prior to the step of installing the second transformer, a step of relocating a device that has been installed on the secondary side of the first transformer after foundation work has been completed, and securing the free space; 4. The transformer replacement method according to claim 1, wherein the transformer is replaced by a transformer having a plurality of wires.

5. In the step of relocating the device, the device includes one or both of a shunt reactor and a neutral point reactor installed on the premises.

5. The transformer replacement method according to claim 4.

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