Overall railway transportation outgoing line structure of grid-side 750kV converter transformer

Abstract

The invention relates to the technical field of transformers, and particularly discloses an integral railway transportation outgoing line structure of a grid-side 750kV converter transformer. The network side 750kV converter transformer integral railway transportation outgoing line structure comprises an oil tank, a network side coil, an iron core side column, a voltage-sharing ball, a supporting hard paper tube and a voltage-sharing pipe, the voltage-sharing ball is arranged on the long axis side of a transformer and is supported by the supporting hard paper tube, the network side outgoing line structure is connected with the network side coil, and the voltage-sharing pipe is connected with the network side coil. The grid side outgoing line structure comprises an outgoing line terminal connected with a power grid, a switch device and a lead. According to the overall railway transportation outgoing line structure of the network side 750kV converter transformer, a plurality of assemblies and structural optimization are combined, the transportation convenience, operation safety and long-term stable operation effect of the transformer are improved, the insulation distances of the oil tank wall, the iron core side column and the clamp web are arranged in a shape-adaptive mode, the transportation size of the transformer is reduced, and the transportation cost is reduced. The network side lead and the transformer body can be integrally transported, and the transportation efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of transformers, and in particular relates to an integral railway transport outgoing line structure of a grid-side 750kV converter transformer. Background Art

[0002] With the continuous development of DC transmission projects, the demand for converter transformers as the main equipment of converter stations is also increasing, and the voltage level is getting higher and higher. The converter transformer adopts a grid-side voltage level of 750kV. The insulation level is increased by 50% on the 500KV level, which theoretically requires more sufficient insulation space and safer insulation structure. However, this product needs to be transported by rail. Due to this limitation, the increase in the main insulation distance is only 10%. The design calculation must not only reasonably arrange the body structure in a limited space to ensure that the insulation distance and margin at all locations fully meet the requirements, but also ensure the mechanical strength and process operability of the product. As a result, the transportation size of the converter transformer is getting larger and larger, which in turn affects the comprehensive development of my country's DC transmission projects. The grid-side lead is one of the most critical components in the converter transformer. Since the 750kV power grid is generally located in the northwest of my country, due to geographical restrictions, railway transportation is the best transportation solution. Railway transportation will strictly limit the transportation width of the transformer, generally requiring the width not to exceed 3.5m, and the distance between the clamp and the box wall will be further reduced. There is even less space for the equalizing ball to be placed between the clamp and the box wall. Therefore, it is meaningless to make improvements based on the original 500kV grid-side outgoing line device, and a completely new structure is urgently needed to meet the engineering needs. Summary of the invention

[0003] The purpose of the present invention is to provide a grid-side 750kV converter transformer integrated railway transportation outgoing line structure with a simple structure and reasonable design in order to solve the above problems.

[0004] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0005] The invention discloses an integrated railway transport outgoing line structure of a grid-side 750kV converter transformer, comprising an oil tank, a grid-side coil, a core side column, a voltage-equalizing ball, a supporting cardboard tube and a voltage-equalizing tube, wherein the voltage-equalizing ball is arranged on the long axis side of the transformer and is supported by the supporting cardboard tube, and further comprises a grid-side outgoing line structure, wherein the grid-side outgoing line structure is connected to the grid-side coil and comprises an outgoing line terminal connected to a power grid, a switch device and a lead wire.

[0006] Furthermore, it also includes a lead wire clamp, which is used to bundle the leads.

[0007] Furthermore, the pressure equalizing tube is arranged between the inner wall of the oil tank and the side column of the iron core.

[0008] Furthermore, the insulation distance between the inner wall of the oil tank and the pressure equalizing pipe is greater than or equal to 390 mm.

[0009] Furthermore, the insulation distance between the core side column and the voltage-equalizing tube is greater than or equal to 900 mm.

[0010] Furthermore, the insulation distance between the web of the lead clamp and the voltage equalizing tube is greater than or equal to 390 mm.

[0011] Furthermore, the pressure equalizing tube adopts an inner and outer double-layer structure design, the inner layer is made of ceramic insulating material, the outer layer is made of aluminum alloy material, and a sealing ring is arranged between the inner and outer layers.

[0012] The beneficial effects of the present invention are as follows: the present invention combines multiple components and structural optimizations to improve the transportation convenience, operational safety and long-term stable operation of the transformer, and by appropriately arranging the insulation distances of the oil tank wall, the core side columns and the clamp web, the internal space utilization rate is improved, the transportation size of the transformer is greatly reduced, the grid-side lead and the body can be transported as a whole, the transportation efficiency is improved, and the safety hazards of repeated disassembly and assembly of the grid-side lead are effectively reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural diagram of the outlet device of the present invention;

[0014] Figure 2 It is a structural diagram of the voltage-equalizing tube of the outlet device of the present invention.

[0015] In the figure: 1. Oil tank; 2. Grid side coil; 3. Core side column; 4. Equalizing ball; 5. Support cardboard tube; 6. Equalizing tube; 7. Lead clamp. DETAILED DESCRIPTION

[0016] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0017] like Figure 1 , Figure 2 As shown, a grid-side 750kV converter transformer integral railway transport outgoing line structure includes an oil tank 1, a grid-side coil 2, a core side column 3, a voltage-equalizing ball 4, a supporting cardboard tube 5 and a voltage-equalizing tube 6, wherein the voltage-equalizing ball 4 is arranged on the long axis side of the transformer, and the voltage-equalizing ball 4 is supported by the supporting cardboard tube 5, and also includes a grid-side outgoing line structure, which is connected to the grid-side coil 2, and includes an outgoing line terminal connected to the power grid, a switch device and a lead.

[0018] The voltage-equalizing ball 4 is used to alleviate the uneven electric field, balance the voltage distribution, avoid local excessive voltage, and reduce the impact of the electric field on various parts of the transformer. The supporting cardboard 5 provides physical support to ensure the stability of the voltage-equalizing ball 4. This design can effectively reduce the concentration of the electric field, improve the electrical safety and stability of the transformer, and avoid failures or damage caused by uneven voltage.

[0019] In a specific implementation manner, a lead wire clamp 7 is also included, and the lead wire clamp 7 is used to bundle the lead wires.

[0020] The lead clamp 7 can effectively manage the leads in the power system, prevent the leads from loosening or being affected by external forces, and ensure stable current transmission;

[0021] Among them, the voltage-equalizing ball 4 is improved from between the original lead clamp 7 and the box wall to the long axis side of the transformer, and the lead voltage-equalizing tube adopts the radial lead-out of the coil end, which greatly reduces the transportation width, so that the grid-side lead and the device body can be transported as a whole, and can be completely transported by rail, effectively reducing the safety hazard of repeated disassembly and assembly of the grid-side lead.

[0022] In a specific implementation, the pressure equalizing tube 6 is arranged between the inner wall of the oil tank 1 and the core side column 3 to form a pressure equalizing system inside the transformer.

[0023] The function of the pressure equalizing tube 6 is to balance the pressure in the oil tank 1 and prevent oil pressure fluctuations caused by temperature changes during operation; the setting of the pressure equalizing tube 6 can ensure the pressure balance inside and outside the oil tank 1 during the operation of the transformer, extend the service life of the transformer, and improve the working stability of the transformer.

[0024] In a specific implementation, the insulation distance between the inner wall of the oil tank 1 and the equalizing tube 6 is greater than or equal to 390 mm, ensuring that there is sufficient insulation distance between the inner wall of the oil tank 1 and the equalizing tube 6 to prevent short circuits or electrical accidents, reduce the risk of electrical insulation failures, and improve the electrical safety of the transformer.

[0025] In a specific implementation, the lead-in voltage-equalizing tube is led out radially from the coil end. The insulation distance between the core side column 3 and the voltage-equalizing tube 6 is greater than or equal to 900 mm; the electrical isolation is enhanced to ensure that there is no electrical contact between the core side column 3 and the voltage-equalizing tube 6, reduce the risk of electrical accidents, and improve the working safety and reliability of the transformer.

[0026] In a specific implementation manner, the insulation distance between the web of the lead clamp 7 and the voltage-equalizing tube 6 is greater than or equal to 390 mm, thereby ensuring the insulation between electrical components, reducing the risk of current leakage, and enhancing the overall safety of the transformer.

[0027] In a specific embodiment, the equalizing tube 6 adopts an inner and outer double-layer structure design, the inner layer is made of aluminum alloy material, the outer layer is made of wet paper material, and the outermost layer is provided with a multi-layer insulating paper tube.

[0028] It should be noted that the inner layer of aluminum alloy material provides excellent mechanical strength and good thermal conductivity, while the outer layer of wet paper blanks and multi-layer insulating paper tubes provide good insulation performance. Through the multi-layer insulating paper tube design, the electrical insulation and mechanical strength of the equalizing tube 6 can be enhanced, the pressure resistance and shock resistance of the transformer can be improved, and the reliability of the equipment during long-term operation can be ensured.

[0029] The present invention adopts reasonable component layout, enhanced insulation distance, double-layer equalizing tube, etc., and the lead equalizing tube adopts radial lead-out of the coil end, which not only optimizes the convenience of transportation, installation and maintenance process, but also improves the safety, stability and working efficiency of the transformer. These characteristics make the transformer have significant technical advantages in the application of high-voltage commutation field.

[0030] As the capacity of the transformer increases, the diameter of the iron core will increase. The diameter of the voltage-equalizing ball 4 will also increase, and the insulation distance itself will be very tight. Therefore, there is no space for the voltage-equalizing ball 4 to be placed between the lead clamp 7 and the box wall. The outlet structure at the end of the grid-side coil 2 greatly reduces the axial height of the grid-side lead. The voltage-equalizing tube is arranged according to Figure 2 As shown, the insulation distances of the oil tank 1 wall, the iron core side column 3, and the web of the lead clamp 7 are appropriately arranged. The voltage-equalizing ball 4 is improved from the original location between the lead clamp 7 and the tank wall to the long axis side of the transformer. The insulation distance of the grid-side lead voltage-equalizing tube 6 to the oil tank wall is ≥390mm, the insulation distance to the iron core side column 3 is ≥900mm, and the insulation distance to the web of the lead clamp 7 is ≥390mm. The electrical environment is very complex, and all data are the optimal results obtained through repeated modeling and calculation. A large insulation distance will affect the production cost, and a small distance will cause discharge.

[0031] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A grid-side 750kV converter transformer integrated railway transport outgoing line structure, characterized in that: The utility model comprises an oil tank (1), a grid-side coil (2), an iron core side column (3), a voltage-equalizing ball (4), a supporting cardboard tube (5) and a voltage-equalizing tube (6), wherein the voltage-equalizing ball (4) is arranged on the long axis side of the transformer, and the voltage-equalizing ball (4) is supported by the supporting cardboard tube (5), and further comprises a grid-side outgoing line structure, wherein the grid-side outgoing line structure is connected to the grid-side coil (2), and the grid-side outgoing line structure comprises an outgoing line terminal connected to the power grid, a switch device and a lead wire.

2. The integrated railway transport outgoing line structure of a grid-side 750kV converter transformer according to claim 1 is characterized in that: It also comprises a lead wire clamp (7), and the lead wire clamp (7) is used for bundling the lead wires.

3. The integrated railway transport outgoing line structure of a grid-side 750kV converter transformer according to claim 2 is characterized in that: The pressure equalizing tube (6) is arranged between the inner wall of the oil tank (1) and the iron core side column (3).

4. The integrated railway transport outgoing line structure of a grid-side 750kV converter transformer according to claim 3 is characterized in that: The insulation distance between the inner wall of the oil tank (1) and the pressure equalizing pipe (6) is greater than or equal to 390 mm.

5. The integrated railway transport outgoing line structure of a grid-side 750kV converter transformer according to claim 4 is characterized in that: The insulation distance between the core side column (3) and the voltage-equalizing tube (6) is greater than or equal to 900 mm.

6. The integrated railway transport outgoing line structure of a grid-side 750kV converter transformer according to claim 5 is characterized in that: The insulation distance between the web of the lead clamp (7) and the voltage equalizing tube (6) is greater than or equal to 390 mm.

7. The integrated railway transport outgoing line structure of a grid-side 750kV converter transformer according to claim 1 is characterized in that: The pressure equalizing tube (6) adopts an inner and outer double-layer structure design, the inner layer is made of ceramic insulating material, the outer layer is made of aluminum alloy material, and a sealing ring is arranged between the inner and outer layers.

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