Small-capacity combined 220kV on-load voltage regulation power transformer

Abstract

The invention provides a small-capacity combined 220kV on-load voltage regulation power transformer, and belongs to the technical field of transformers. The invention provides a small-capacity combined 220kV on-load voltage regulation power transformer which comprises an R single-phase transformer, an S single-phase transformer and a T single-phase transformer, a first elastic tube for connecting the R single-phase transformer and the S single-phase transformer is arranged between the R single-phase transformer and the S single-phase transformer, and a second elastic tube for connecting the S single-phase transformer and the T single-phase transformer is arranged between the S single-phase transformer and the T single-phase transformer. The R single-phase transformer is provided with an R-phase low-voltage bushing and an R-phase high-voltage bushing, the T single-phase transformer is provided with a T-phase low-voltage bushing and a T-phase high-voltage bushing, and the S single-phase transformer is provided with an S-phase low-voltage bushing, an S-phase high-voltage bushing, an on-load tap changer and an oil conservator. The invention provides a small-capacity combined 220kV on-load voltage regulation power transformer. The small-capacity combined 220kV on-load voltage regulation power transformer is formed by independently transporting an R single-phase transformer, an S single-phase transformer and a T single-phase transformer and combining and installing on site.

Description

Technical Field

[0001] The invention belongs to the technical field of transformers, and in particular relates to a small-capacity combined 220kV on-load voltage-regulating power transformer. Background Art

[0002] Transformers are commonly used electrical equipment in power transmission and transformation projects. In order to meet the high voltage requirements of power transmission and transformation projects, the size of transformers has increased. In the process of transporting large transformers to the installation site, there are many difficulties in transportation due to road conditions, bridge weight restrictions, height restrictions, etc. In order to meet transportation conditions, the size of the transformer is limited, sacrificing product reliability. According to actual needs, it is sometimes necessary to build a factory near the transformer installation site for the production and assembly of the transformer, which increases the workload at the installation site. Summary of the invention

[0003] The purpose of the present invention is to provide a small-capacity combined 220kV on-load voltage-regulating power transformer, aiming to solve the problem that large-volume transformers are difficult to transport.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide a small-capacity combined 220kV on-load voltage-changing power transformer, comprising an R single-phase transformer, an S single-phase transformer and a T single-phase transformer arranged in sequence from left to right, a first elastic tube connecting the R single-phase transformer and the S single-phase transformer is arranged between the two, a second elastic tube connecting the two is arranged between the S single-phase transformer and the T single-phase transformer, the R single-phase transformer is provided with an R-phase low-voltage bushing and an R-phase high-voltage bushing, the T single-phase transformer is provided with a T-phase low-voltage bushing and a T-phase high-voltage bushing, the S single-phase transformer is provided with an S-phase low-voltage bushing, an S-phase high-voltage bushing, an on-load voltage-changing switch and an oil storage cabinet.

[0005] In a possible implementation, an R-phase radiator is provided on one side of the R single-phase transformer, and the R single-phase transformer is connected to the R-phase radiator through an R-phase heat dissipation pipeline, an S-phase radiator is provided on one side of the S single-phase transformer, and the S single-phase transformer is connected to the S-phase radiator through an S-phase heat dissipation pipeline, and a T-phase radiator is provided on one side of the T single-phase transformer, and the T single-phase transformer is connected to the T-phase radiator through a T-phase heat dissipation pipeline.

[0006] In a possible implementation, the S-phase heat dissipation pipeline includes a first S-phase heat dissipation pipe and a second S-phase heat dissipation pipe arranged in parallel, the first S-phase heat dissipation pipe is arranged on the left side of the second S-phase heat dissipation pipe, the first end of the first S-phase heat dissipation pipe is arranged on the S-phase radiator, the second end of the first S-phase heat dissipation pipe is arranged on the upper end surface of the S single-phase transformer and is arranged close to the S-phase radiator, the first end of the second S-phase heat dissipation pipe is arranged on the radiator, and the second end of the second S-phase heat dissipation pipe is arranged on the upper end surface of the S single-phase transformer and is arranged away from the S-phase radiator.

[0007] In a possible implementation, a high-voltage neutral point bushing is provided on the R single-phase transformer.

[0008] In a possible implementation, the first elastic tube and the second elastic tube are suitable for passing the high-voltage leads and low-voltage leads of the R single-phase transformer, the S single-phase transformer and the T single-phase transformer. The high-voltage leads of the R single-phase transformer, the S single-phase transformer and the T single-phase transformer are connected to the on-load tap-changing switch, and the on-load tap-changing switch is connected to the high-voltage neutral point bushing through the switch lead. The low-voltage leads of the R single-phase transformer, the S single-phase transformer and the T single-phase transformer form a D connection.

[0009] In a possible implementation, the side walls of the R single-phase transformer, the S single-phase transformer, and the T single-phase transformer are all provided with operation square holes, and the operation square holes are used for passing the high-voltage lead wire / low-voltage lead wire.

[0010] In a possible implementation, a switch oil filter is provided on the S single-phase transformer, and the switch oil filter is connected to the on-load tap changer.

[0011] In a possible implementation, the S single-phase transformer is provided with a switch electric mechanism, and the switch electric mechanism is connected to control the on-load tap-changing switch.

[0012] In a possible implementation, the S-phase box cover of the S single-phase transformer includes an S-phase horizontal portion and an S-phase inclined portion, the S-phase inclined portion is arranged to be inclined downward relative to the S-phase horizontal portion, the S-phase low-voltage bushing is arranged on the S-phase horizontal portion, and the S-phase high-voltage bushing is arranged on the S-phase inclined portion.

[0013] In a possible implementation manner, the S-phase high-voltage bushing is arranged perpendicular to the S-phase inclined portion.

[0014] The beneficial effects of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention are: Compared with the prior art, an R single-phase transformer, an S single-phase transformer and a T single-phase transformer are provided, and the R single-phase transformer, the S single-phase transformer and the T single-phase transformer are provided in sequence and assembled and installed at the installation site to form a three-phase on-load voltage-regulating power transformer. The R single-phase transformer is connected to the S single-phase transformer through a first elastic tube, and the S single-phase transformer is connected to the T single-phase transformer through a second elastic tube. The first elastic tube and the second elastic tube can be extended or compressed in length and adjusted according to the on-site construction conditions. The R single-phase transformer is provided with an R-phase low-voltage bushing and an R-phase high-voltage bushing, the T single-phase transformer is provided with a T-phase low-voltage bushing and a T-phase high-voltage bushing, the S single-phase transformer is provided with an S-phase low-voltage bushing, an S-phase high-voltage bushing, an on-load voltage-regulating switch and an oil storage cabinet, and the R single-phase transformer, the S single-phase transformer and the T single-phase transformer are three single-phase transformers. The three-phase transformers can be transported separately, which reduces the difficulty of transportation. They can be assembled on site, which reduces the requirements for the installation site and improves the assembly efficiency. The performance is stable and reliable. The three separate single-phase transformers are equipped with their own low-voltage bushings and high-voltage bushings to reduce the DC resistance imbalance that may be caused by the common box riser. The S single-phase transformer is also equipped with an on-load voltage regulator and an oil storage cabinet. The on-load voltage regulator and the oil storage cabinet are used for the entire three-phase on-load voltage regulator power transformer. The components of the three-phase on-load voltage regulator power transformer are disassembled to further reduce the vehicle load, which is convenient for transportation on bridges with poor load-bearing capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 A schematic diagram of the top view of a small-capacity combined 220kV on-load voltage-regulating power transformer provided in an embodiment of the present invention; Figure 2 A schematic diagram of the top view of the on-load voltage regulating switch used in an embodiment of the present invention; Figure 3 A schematic diagram of the structure of a first high-pressure side elastic tube used in an embodiment of the present invention; Figure 4 A schematic diagram of the internal structure of the first high-pressure side elastic tube used in an embodiment of the present invention; Figure 5 It is a partial left-view structural schematic diagram of the S single-phase transformer adopted in the embodiment of the present invention.

[0017] In the figure: 1, R single-phase transformer; 2, R phase low-voltage bushing; 3, R phase high-voltage bushing; 4, R phase radiator; 5, first R phase heat pipe; 6, second R phase heat pipe; 7, R single-phase front operation square hole; 8, R single-phase front copper bar; 9, S single-phase transformer; 10, S phase low-voltage bushing; 11, S phase high-voltage bushing; 12, on-load voltage regulating switch; 13, switch oil filter; 14, switch electric mechanism; 15, S phase radiator; 16, first S phase heat pipe; 17, second S phase heat pipe; 18, S single-phase front operation Make a square hole; 19, S single-phase front copper bar; 20, S phase horizontal part; 21, S phase inclined part; 22, oil storage cabinet; 23, T single-phase transformer; 24, T phase low-voltage bushing; 25, T phase high-voltage bushing; 26, T phase radiator; 27, first T phase heat dissipation pipe; 28, second T phase heat dissipation pipe; 29, first low-voltage side elastic tube; 30, first high-voltage side elastic tube; 31, second low-voltage side elastic tube; 32, second high-voltage side elastic tube; 33, first high-voltage connecting wire; 34, wire clamp; 35, high-voltage neutral point bushing. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] Please refer to Figure 1 as well as Figure 2 A specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention is now described, comprising an R single-phase transformer 1, an S single-phase transformer 9 and a T single-phase transformer 23 arranged in sequence from left to right, a first elastic tube connecting the R single-phase transformer 1 and the S single-phase transformer 9 is arranged between the two, a second elastic tube connecting the two is arranged between the S single-phase transformer 9 and the T single-phase transformer 23, the R single-phase transformer 1 is provided with an R-phase low-voltage bushing 2 and an R-phase high-voltage bushing 3, the T single-phase transformer 23 is provided with a T-phase low-voltage bushing 24 and a T-phase high-voltage bushing 25, the S single-phase transformer 9 is provided with an S-phase low-voltage bushing 10, an S-phase high-voltage bushing 11, an on-load voltage-regulating switch 12 and an oil storage cabinet 22.

[0020] The present invention provides a small-capacity combined 220kV on-load voltage-regulating power transformer. Compared with the prior art, the present invention is provided with an R single-phase transformer 1, an S single-phase transformer 9 and a T single-phase transformer 23. The R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23 are arranged in sequence and assembled and installed at the installation site to form a three-phase on-load voltage-regulating power transformer. The R single-phase transformer 1 is connected to the S single-phase transformer 9 through a first elastic tube, and the S single-phase transformer 9 is connected to the T single-phase transformer 23 through a second elastic tube. The first elastic tube and the second elastic tube can be extended or compressed in length and adjusted according to the on-site construction conditions. The R single-phase transformer 1 is provided with an R-phase low-voltage bushing 2 and an R-phase high-voltage bushing 3, the T single-phase transformer 23 is provided with a T-phase low-voltage bushing 24 and a T-phase high-voltage bushing 25, the S single-phase transformer 9 is provided with an S-phase low-voltage bushing 10, an S-phase high-voltage bushing 11, an on-load voltage-regulating switch 12 and an oil storage cabinet 22, the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase The transformer 23 is composed of three separate single-phase transformers, which can be transported separately, reducing the difficulty of transportation. They can be assembled on site, reducing the requirements for the installation site, improving the assembly efficiency, and having stable and reliable performance. The three separate single-phase transformers are each provided with their own low-voltage bushing and high-voltage bushing to reduce the DC resistance imbalance that may be caused by the common box riser. The S single-phase transformer 9 is also provided with an on-load voltage regulating switch 12 and an oil conservator 22, which are used by the entire three-phase on-load voltage regulating power transformer. The components of the three-phase on-load voltage regulating power transformer are disassembled to further reduce the vehicle load, making it easier to transport on bridges with poor load-bearing capacity.

[0021] For details, please refer to Figure 1 as well as Figure 2, including an R single-phase transformer 1, an S single-phase transformer 9 and a T single-phase transformer 23, the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23 are arranged sequentially from left to right, the R single-phase transformer 1 is connected to the S single-phase transformer 9 through a first elastic tube, the S single-phase transformer 9 is connected to the T single-phase transformer 23 through a second elastic tube, the R phase low-voltage bushing 2 arranged on the R single-phase transformer 1, the S phase low-voltage bushing 10 arranged on the S single-phase transformer 9, and the T phase low-voltage bushing 24 arranged on the T single-phase transformer 23 are all arranged on the rear side of the device, the R phase high voltage bushing arranged on the R single-phase transformer 1 The bushing 3, the S-phase high-voltage bushing 11 arranged on the S single-phase transformer 9, and the T-phase high-voltage bushing 25 arranged on the T single-phase transformer 23 are all arranged on the front side of the device, the on-load voltage regulating switch 12 is arranged inside the S single-phase transformer 9, in the horizontal direction, the on-load voltage regulating switch 12 is arranged in the middle of the S single-phase transformer 9, and is arranged close to the R single-phase transformer 1, the oil conservator 22 is erected above the S single-phase transformer 9, in the horizontal direction, the oil conservator 22 is arranged in the middle of the S single-phase transformer 9, and is arranged close to the T single-phase transformer 23, and the oil conservator 22 supplies oil to the entire combined three-phase on-load voltage regulating power transformer.

[0022] As a specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention, please refer to Figure 1 as well as Figure 2 An R-phase radiator 4 is provided on one side of the R single-phase transformer 1, and the R single-phase transformer 1 is connected to the R-phase radiator 4 through an R-phase heat dissipation pipeline. An S-phase radiator 15 is provided on one side of the S single-phase transformer 9, and the S single-phase transformer 9 is connected to the S-phase radiator 15 through an S-phase heat dissipation pipeline. A T-phase radiator 26 is provided on one side of the T single-phase transformer 23, and the T single-phase transformer 23 is connected to the T-phase radiator 26 through a T-phase heat dissipation pipeline.

[0023] For details, please refer to Figure 1 as well as Figure 2 The rear side of the R single-phase transformer 1 is connected to the R-phase radiator 4 through the R-phase heat dissipation pipeline, the rear side of the S single-phase transformer 9 is connected to the S-phase radiator 15 through the S-phase heat dissipation pipeline, and the rear side of the T single-phase transformer 23 is connected to the T-phase radiator 26 through the T-phase heat dissipation pipeline. The three separate single-phase transformers are connected to their own radiators to enhance the heat dissipation effect.

[0024] As a specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention, please refer to Figure 1 as well as Figure 2The S-phase heat dissipation pipeline includes a first S-phase heat dissipation pipe 16 and a second S-phase heat dissipation pipe 17 which are arranged in parallel. The first S-phase heat dissipation pipe 16 is arranged on the left side of the second S-phase heat dissipation pipe 17. The first end of the first S-phase heat dissipation pipe 16 is arranged on the S-phase radiator 15. The second end of the first S-phase heat dissipation pipe 16 is arranged on the upper end surface of the S single-phase transformer 9 and is arranged close to the S-phase radiator 15. The first end of the second S-phase heat dissipation pipe 17 is arranged on the radiator. The second end of the second S-phase heat dissipation pipe 17 is arranged on the upper end surface of the S single-phase transformer 9 and is arranged away from the S-phase radiator 15.

[0025] For details, please refer to Figure 1 as well as Figure 2 The S-phase heat dissipation pipeline includes a first S-phase heat dissipation pipe 16 and a second S-phase heat dissipation pipe 17. The first S-phase heat dissipation pipe 16 and the second S-phase heat dissipation pipe 17 are arranged in parallel. The first end of the first S-phase heat dissipation pipe 16 is arranged on the radiator, and the second end of the first S-phase heat dissipation pipe 16 is arranged on the left side of the upper end surface of the S single-phase transformer 9, and is arranged close to the S-phase radiator 15. The first end of the second S-phase heat dissipation pipe 17 is arranged on the S-phase radiator 15, and the second end of the second S-phase heat dissipation pipe 17 is arranged on the right side of the upper end surface of the S single-phase transformer 9, and is arranged away from the S-phase radiator 15. The first S-phase heat dissipation pipe 16 and the second S-phase heat dissipation pipe 17 are arranged away from the on-load voltage regulating switch 12 and the oil storage cabinet 22.

[0026] For details, please refer to Figure 1 as well as Figure 2 The R-phase heat dissipation pipeline includes a first R-phase heat dissipation pipe 5 and a second R-phase heat dissipation pipe 6. The first R-phase heat dissipation pipe 5 and the second R-phase heat dissipation pipe 6 are arranged in parallel. The first R-phase heat dissipation pipe 5 is arranged on the left side of the second R-phase heat dissipation pipe 6. The first end of the first R-phase heat dissipation pipe 5 is arranged on the R-phase radiator 4. The second end of the first R-phase heat dissipation pipe 5 is arranged in the middle of the upper end surface of the R single-phase transformer 1. The first end of the second R-phase heat dissipation pipe 6 is arranged on the radiator. The second end of the second R-phase heat dissipation pipe 6 is arranged in the middle of the upper end surface of the R single-phase transformer 1; T-phase heat dissipation pipeline It includes a first T-phase heat dissipation pipe 27 and a second T-phase heat dissipation pipe 28. The first T-phase heat dissipation pipe 27 and the second T-phase heat dissipation pipe 28 are arranged in parallel. The first T-phase heat dissipation pipe 27 is arranged on the left side of the second T-phase heat dissipation pipe 28. The first end of the first T-phase heat dissipation pipe 27 is arranged on the T-phase radiator 26, and the second end of the first T-phase heat dissipation pipe 27 is arranged in the middle of the upper end surface of the T single-phase transformer 23. The first end of the second T-phase heat dissipation pipe 28 is arranged on the radiator, and the second end of the second T-phase heat dissipation pipe 28 is arranged in the middle of the upper end surface of the T single-phase transformer 23.

[0027] As a specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention, please refer to Figure 1 as well as Figure 2 A high voltage neutral point bushing 35 is provided on the R single-phase transformer 1.

[0028] For details, please refer to Figure 1 as well as Figure 2 The high-voltage neutral point bushing 35 is arranged at the left end of the upper end surface of the R single-phase transformer 1 and is arranged close to the R phase radiator 4.

[0029] As a specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention, please refer to Figures 1 to 4 The first elastic tube and the second elastic tube are suitable for passing the high-voltage leads and low-voltage leads of the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23. The high-voltage leads of the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23 are connected to the on-load tap-changing switch 12, and the on-load tap-changing switch 12 is connected to the high-voltage neutral point bushing 35 through the switch lead. The low-voltage leads of the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23 form a D connection.

[0030] For details, please refer to Figures 1 to 4 The first elastic tube and the second elastic tube establish a channel for the high-voltage lead and the low-voltage lead. The first elastic tube includes a first low-voltage side elastic tube 29 and a first high-voltage side elastic tube 30. The first low-voltage side elastic tube 29 is arranged at the rear side of the first high-voltage side elastic tube 30. The second elastic tube includes a second low-voltage side elastic tube 31 and a second high-voltage side elastic tube 32. The second low-voltage side elastic tube 31 is arranged at the rear side of the second high-voltage side elastic tube 32. The high-voltage lead of the R single-phase transformer 1 enters the S single-phase transformer 9 through the first high-voltage side elastic tube 30 and is connected to the on-load tap changer 12. The high-voltage lead of the T single-phase transformer 23 enters the S single-phase transformer 9 through the second high-voltage side elastic tube 30 and is connected to the on-load tap changer 12. The side elastic tube 32 enters the T single-phase transformer 23 and is connected to the on-load tap-changing switch 12. The high-voltage lead of the S single-phase transformer 9 is connected to the on-load tap-changing switch 12. The switch lead of the on-load tap-changing switch 12 passes through the first low-voltage side elastic tube 29 to connect to the high-voltage neutral point bushing 35. The low-voltage lead of the R single-phase transformer 1 enters the S single-phase transformer 9 through the first low-voltage side elastic tube 29. The low-voltage lead of the T single-phase transformer 23 enters the S single-phase transformer 9 through the second low-voltage side elastic tube 31. The low-voltage leads of the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23 form a D connection in the S single-phase transformer 9.

[0031] As a specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention, please refer to Figures 1 to 4 The side walls of the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23 are all provided with operation square holes, which are used for passing the high-voltage lead wire / low-voltage lead wire.

[0032] For details, please refer to Figures 1 to 4, operation square holes are provided on the front and rear side walls of the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23, a first high-voltage connecting line 33 is provided in the first high-voltage side elastic tube 30, an R single-phase front operation square hole 7 is provided on the front side wall of the R single-phase transformer 1, and is arranged close to the first high-voltage side elastic tube 30, an R single-phase front copper busbar 8 is provided in the R single-phase transformer 1, an S single-phase front operation square hole 18 is provided on the front side wall of the S single-phase transformer 9, and is arranged close to the first high-voltage side elastic tube 30, an S single-phase front copper busbar 19 is provided in the S single-phase transformer 9, and a high-voltage lead of the R single-phase transformer 1 The R single-phase front copper bar 8 is connected, the R single-phase front copper bar 8 is connected to the S single-phase front copper bar 19 through the first high-voltage connecting line 33, the S single-phase front copper bar 19 is connected to the on-load tap changer 12 through the connecting cable, the R single-phase front operation square hole 7 is arranged on the front side of the R single-phase front copper bar 8, and the S single-phase front operation square hole 18 is arranged on the front side of the S single-phase front copper bar 19, the R single-phase front operation square hole 7 and the S single-phase front operation square hole 18 are convenient for operation on the R single-phase front copper bar 8 and the S single-phase front copper bar 19, and the corresponding other operation square holes of the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23 have the same function.

[0033] For further information, please refer to Figures 1 to 4 A wire clamp 34 is provided inside the first high-pressure side elastic tube 30. Two groups of wire clamps 34 are respectively provided at both ends of the first high-pressure side elastic tube 30 to comb the various connecting wires inside the first high-pressure side elastic tube 30. Correspondingly, a wire clamp 34 is provided inside the first low-pressure side elastic tube 29, the second high-pressure side elastic tube 32, and the second low-pressure side elastic tube 31.

[0034] As a specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention, please refer to Figure 1 as well as Figure 2 The S single-phase transformer 9 is provided with a switch oil filter 13, and the switch oil filter 13 is connected to the on-load voltage regulator 12.

[0035] For details, please refer to Figure 1 as well as Figure 2 The switch oil filter 13 is arranged on the rear side wall of the S single-phase transformer 9 , and the switch oil filter 13 is connected to the on-load voltage regulating switch 12 .

[0036] As a specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention, please refer to Figure 1 as well as Figure 2 The S single-phase transformer 9 is provided with a switch electric mechanism 14, and the switch electric mechanism 14 is connected to control the on-load voltage regulating switch 12.

[0037] For details, please refer to Figure 1 as well as Figure 2The switch electric mechanism 14 is arranged on the front side wall of the S single-phase transformer 9 , and the switch electric mechanism 14 is electrically connected to the on-load tap-changing switch 12 .

[0038] As a specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention, please refer to Figure 1 as well as Figure 5 The S-phase box cover of the S single-phase transformer 9 includes an S-phase horizontal portion 20 and an S-phase inclined portion 21. The S-phase inclined portion 21 is arranged to be inclined downward relative to the S-phase horizontal portion 20. The S-phase low-voltage bushing 10 is arranged on the S-phase horizontal portion 20, and the S-phase high-voltage bushing 11 is arranged on the S-phase inclined portion 21.

[0039] For details, please refer to Figure 1 as well as Figure 5 The box cover structures of the R single-phase transformer 1, the S single-phase transformer 9 and the T single-phase transformer 23 are similar. The S-phase box cover of the S single-phase transformer 9 includes an S-phase horizontal portion 20 and an S-phase inclined portion 21. The S-phase inclined portion 21 is arranged at the front side of the S-phase horizontal portion 20, and the S-phase inclined portion 21 is inclined downward. Reinforcing irons of matching shapes are arranged on the left and right sides of the S-phase box cover. The S-phase low-voltage bushing 10 is arranged on the S-phase horizontal portion 20, and the S-phase high-voltage bushing 11 is arranged on the S-phase inclined portion 21, which helps to increase the internal space of the S single-phase transformer 9 and avoid overheating.

[0040] As a specific implementation of a small-capacity combined 220kV on-load voltage-regulating power transformer provided by the present invention, please refer to Figure 1 as well as Figure 5 The S-phase high-voltage bushing 11 is arranged perpendicular to the S-phase inclined portion 21 .

[0041] For details, please refer to Figure 1 as well as Figure 5 , the S-phase high-voltage bushing 11 is perpendicular to the S-phase inclined portion 21 .

[0042] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A small capacity combined 220kV on-load voltage regulating power transformer, characterized in that: It includes an R single-phase transformer, an S single-phase transformer and a T single-phase transformer arranged in sequence from left to right, a first elastic tube connecting the R single-phase transformer and the S single-phase transformer is arranged between the two, a second elastic tube connecting the S single-phase transformer and the T single-phase transformer is arranged between the two, the R single-phase transformer is provided with an R-phase low-voltage bushing and an R-phase high-voltage bushing, the T single-phase transformer is provided with a T-phase low-voltage bushing and a T-phase high-voltage bushing, the S single-phase transformer is provided with an S-phase low-voltage bushing, an S-phase high-voltage bushing, an on-load voltage regulating switch and an oil storage cabinet.

2. A small-capacity combined 220kV on-load voltage-changing power transformer as claimed in claim 1, characterized in that: An R-phase radiator is provided on one side of the R single-phase transformer, and the R single-phase transformer is connected to the R-phase radiator through an R-phase heat dissipation pipeline. An S-phase radiator is provided on one side of the S single-phase transformer, and the S single-phase transformer is connected to the S-phase radiator through an S-phase heat dissipation pipeline. A T-phase radiator is provided on one side of the T single-phase transformer, and the T single-phase transformer is connected to the T-phase radiator through a T-phase heat dissipation pipeline.

3. A small-capacity combined 220kV on-load voltage-changing power transformer as claimed in claim 2, characterized in that: The S-phase heat dissipation pipeline includes a first S-phase heat dissipation pipe and a second S-phase heat dissipation pipe arranged in parallel, the first S-phase heat dissipation pipe is arranged on the left side of the second S-phase heat dissipation pipe, the first end of the first S-phase heat dissipation pipe is arranged on the S-phase radiator, the second end of the first S-phase heat dissipation pipe is arranged on the upper end surface of the S single-phase transformer and is arranged close to the S-phase radiator, the first end of the second S-phase heat dissipation pipe is arranged on the radiator, and the second end of the second S-phase heat dissipation pipe is arranged on the upper end surface of the S single-phase transformer and is arranged away from the S-phase radiator.

4. A small-capacity combined 220kV on-load voltage-changing power transformer as claimed in claim 1, characterized in that: The R single-phase transformer is provided with a high-voltage neutral point bushing.

5. A small-capacity combined 220kV on-load voltage-changing power transformer as claimed in claim 4, characterized in that: The first elastic tube and the second elastic tube are suitable for the passage of the high-voltage leads and low-voltage leads of the R single-phase transformer, the S single-phase transformer and the T single-phase transformer. The high-voltage leads of the R single-phase transformer, the S single-phase transformer and the T single-phase transformer are connected to the on-load tap-changing switch, and the on-load tap-changing switch is connected to the high-voltage neutral point bushing through the switch leads. The low-voltage leads of the R single-phase transformer, the S single-phase transformer and the T single-phase transformer form a D connection.

6. A small-capacity combined 220kV on-load voltage-changing power transformer as claimed in claim 5, characterized in that: The side walls of the R single-phase transformer, the S single-phase transformer and the T single-phase transformer are all provided with operation square holes, and the operation square holes are used for passing the high-voltage lead wire / low-voltage lead wire.

7. A small-capacity combined 220kV on-load voltage-changing power transformer as claimed in claim 1, characterized in that: The S single-phase transformer is provided with a switch oil filter, and the switch oil filter is connected to the on-load voltage regulating switch.

8. A small-capacity combined 220kV on-load voltage-changing power transformer as claimed in claim 1, characterized in that: The S single-phase transformer is provided with an electric switch mechanism, and the electric switch mechanism is connected to control the on-load voltage regulating switch.

9. A small-capacity combined 220kV on-load voltage-changing power transformer as claimed in claim 1, characterized in that: The S-phase box cover of the S single-phase transformer includes an S-phase horizontal portion and an S-phase inclined portion, wherein the S-phase inclined portion is arranged to be inclined downward relative to the S-phase horizontal portion, the S-phase low-voltage bushing is arranged on the S-phase horizontal portion, and the S-phase high-voltage bushing is arranged on the S-phase inclined portion.

10. A small-capacity combined 220kV on-load voltage-changing power transformer as claimed in claim 9, characterized in that: The S-phase high-voltage bushing is arranged perpendicular to the S-phase inclined portion.

Images