Power transformer for box-type substation

Abstract

The power transformer comprises an oil conservator, an oil tank and finned radiators, the oil conservator is a square capsule type oil conservator, an off-circuit tap switch is arranged on a tank cover of the oil tank and connected with a primary winding of the transformer in the oil tank through a tap lead, and the finned radiators are arranged at the front end and the rear end of the oil tank and communicated with the oil tank. The left side wall and the right side wall of the oil tank are respectively provided with an ascending flanged base which is connected with a high-voltage bushing and a low-voltage bushing, the high-voltage bushing and the low-voltage bushing are vertically arranged, the ascending flanged bases are communicated with the oil tank, a primary side lead is connected with the high-voltage bushing through the ascending flanged bases, a secondary side lead is connected with the low-voltage bushing through the ascending flanged bases, and primary and secondary side secondary outgoing lines are outgoing through bushing sides. High and low voltage outgoing line cabinets are directly butted, so that bus connection with a switch cabinet is facilitated, and space is saved; the oil conservator is of a square capsule type structure, the overall height of the transformer is reduced, and the problems that a box-type substation is large in occupied space, difficult to transport and troublesome in field assembly due to the fact that a transformer of a traditional structure is large in size are solved.

Description

Technical Field

[0001] This utility model relates to the field of transformer equipment, specifically a power transformer for a prefabricated substation. Background Technology

[0002] With increasing global attention to new energy sources, the development of new energy power generation is accelerating. Transformers, as an indispensable part of the power system, are playing an increasingly important role in the development of new energy. As power generation equipment technology advances, in order to improve the efficiency of power transmission, power generation and transmission equipment are constantly developing towards larger capacities. However, wind power and photovoltaic power generation are generally distributed in remote areas, and the traditional box-type substation structure is outdated. Some structural designs are unreasonable, resulting in problems such as excessive product size, transportation difficulties, and troublesome on-site assembly. This places higher demands on the capacity, structural compactness, and operational reliability of power transformers used in box-type substations. Utility Model Content

[0003] To address the aforementioned issues, this utility model provides a box-type power transformer for substations, which features a more rational structural design and advantages such as small size, compact structure, high insulation strength, and strong short-circuit withstand capability.

[0004] To achieve the aforementioned objectives, the technical solution adopted by this utility model is as follows:

[0005] A prefabricated power transformer for a substation includes an oil conservator, an oil tank, and a plate-type radiator. The oil conservator is a square capsule-shaped oil conservator, fixedly installed on the top of the oil tank. The oil tank cover is equipped with a no-excitation tap changer connected to the primary winding of the transformer inside the oil tank via tap leads. Plate-type radiators are installed at the front and rear ends of the oil tank and are connected to the oil tank. Elevation seats are respectively installed on the left and right sides of the oil tank and connected to high-voltage bushings and low-voltage bushings. The high-voltage bushings and low-voltage bushings are arranged vertically and fixedly installed on the outside of the elevation seats. The elevation seats are connected to the oil tank. A manhole and manhole cover are provided on one side of the elevation seats. The primary side lead is connected to the high-voltage bushing through the elevation seats, and the secondary side lead is connected to the low-voltage bushing through the elevation seats.

[0006] The finned radiator is connected to the oil tank in a direct-mounted manner, with the radiator connecting flange to the oil tank being directly mounted on the oil tank via bolts.

[0007] The transformer body inside the oil tank is connected to the oil tank cover by screws and nuts. The bottom of the transformer body is fixed to the positioning pins on the oil tank by pads to prevent the body from shifting during transportation. The overall structure can be lowered into or lifted out of the oil tank without draining the oil, which facilitates the inspection and maintenance of the product.

[0008] Furthermore, the riser seat has a cuboid structure. Circular holes are provided at the connection points between the high-voltage bushing and the low-voltage bushing and the riser seat, and sealing gaskets are installed for sealing. Studs for fixing the bushings are welded to the riser seat. A hand hole is provided on one side of the riser seat, and a hand hole flange is welded on it. After connecting the transformer lead to the conductive rod of the high-voltage bushing through the hand hole, a sealing gasket is installed on the hand hole flange. The hand hole cover plate and the hand hole flange are connected by bolts to achieve the sealing of the oil tank riser seat.

[0009] The primary winding of the transformer is provided with tap turns, which are connected to a no-excitation tap changer via tap leads, so as to facilitate adjustment of the number of tap turns of the primary winding, realize voltage regulation, and meet the power supply quality requirements caused by system voltage fluctuations.

[0010] The primary and secondary winding insulation paper tubes of this transformer are made of T4 insulating hard paper tubes, which improves the radial withstand capability of the windings when short-circuited.

[0011] Iron yoke insulation is placed at the upper and lower ends of the primary and secondary windings of the transformer. A pressure plate is set on the outer layer of the iron yoke insulation. The outer side of the pressure plate contacts the inner side of the iron yoke. The setting of the pressure plate, together with the vertical pull screw and clamp on the iron core, compresses the coil and improves the axial short circuit withstand capacity of the winding.

[0012] The beneficial effects of this utility model are as follows:

[0013] This utility model adopts a primary and secondary side lead-out line that directly exits through the riser on the bushing side, directly connecting to the high and low voltage outgoing line cabinet, facilitating connection with the busbar of the switchgear; the oil conservator adopts a square capsule-type structure, effectively reducing the overall height of the transformer; the plate radiator adopts a direct-mounted type, effectively reducing the overall width of the transformer. Compared with the traditional box-type substation, the overall structure is more compact, smaller in size, lower in cost, and lighter in weight, solving the problems of difficult transportation and troublesome on-site assembly. At the same time, it has the characteristics of high insulation strength and strong short-circuit withstand capability. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the main structure of an embodiment of the present utility model;

[0015] Figure 2 for Figure 1 A top-view structural diagram;

[0016] Figure 3 This is a schematic diagram of the transformer body structure;

[0017] Figure 4 This is a schematic diagram of the lifting seat structure.

[0018] 1. Oil conservator; 2. Iron core; 3. Plate radiator; 4. Low-voltage bushing; 5. High-voltage bushing; 6. Screw; 7. No-excitation tap changer; 8. Primary winding; 9. Secondary winding; 10. Yoke insulation; 11. Pressure plate; 12. Insulating paper tube; 13. Elevator seat; 14. Handhole cover; 15. Oil tank; 16. Tank cover; 17. Conductive rod; 18. Stud. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings:

[0020] As attached Figure 1-4 The diagram shows a prefabricated power transformer for a substation, comprising an oil conservator 1, an oil tank 15, a plate radiator 3, and an iron core 2. The oil conservator 1 is a square capsule-shaped oil conservator, fixedly installed on the top of the oil tank 15. The oil tank cover 16 is equipped with a de-energized tap changer 7, which is connected to the primary winding 8 of the transformer inside the oil tank via tap leads. Plate radiators are installed at the front and rear ends of the oil tank and are connected to the oil tank. Elevation seats are respectively installed on the left and right sides of the oil tank and are connected to the high-voltage bushing 5 and the low-voltage bushing 4. The high-voltage bushing 5 and the low-voltage bushing 4 are arranged vertically and fixedly installed on the outside of the elevation seats. The elevation seats are connected to the oil tank. A manhole and a manhole cover are provided on one side of the elevation seats. The primary side lead is connected to the high-voltage bushing 5 through the elevation seats, and the secondary side lead is connected to the low-voltage bushing 4 through the elevation seats.

[0021] The finned radiator 3 is connected to the oil tank in a direct-hanging manner, with the radiator connecting flange of the finned radiator to the oil tank being directly hung on the oil tank by bolts.

[0022] The transformer body inside the oil tank 15 is connected to the oil tank cover by screws 6 and nuts. The bottom of the transformer body is fixed to the positioning pins on the oil tank by pads to prevent the body from shifting during transportation. The overall structure can be lowered into or lifted out of the oil tank without draining the oil, which facilitates the inspection and maintenance of the product.

[0023] Furthermore, the riser seat 13 has a cuboid structure. Circular holes are provided at the connection points between the high-voltage bushing 5 and the low-voltage bushing 4 and the riser seat, and sealing gaskets are installed for sealing. The riser seat is welded with studs 18 for fixing the bushings. A hand hole is provided on one side of the riser seat, and a hand hole flange is welded on it. The riser seat is connected to the oil tank. The transformer lead can be connected to the conductive rod 17 of the high-voltage bushing 5 through the hand hole. A sealing gasket is installed on the hand hole flange, and the hand hole cover plate 14 and the hand hole flange are connected by bolts to achieve the sealing of the oil tank riser seat.

[0024] The primary winding of the transformer is provided with tap turns, which are connected to the no-excitation tap switch through tap leads, so as to facilitate the adjustment of the number of tap turns of the primary winding 8, realize voltage regulation, and meet the power supply quality requirements caused by system voltage fluctuations.

[0025] The primary winding 8 and secondary winding 9 of this transformer use T4 insulating paper tubes, which improves the radial withstand capability of the windings during short circuits.

[0026] Iron yoke insulation 10 is placed at the upper and lower ends of the primary winding 8 and the secondary winding 9 of the transformer. A pressure plate 11 is provided on the outer layer of the iron yoke insulation 10. The outer side of the pressure plate contacts the inner side of the iron yoke. The setting of the pressure plate, together with the vertical pull screw and clamp on the iron core, compresses the coil and improves the axial short circuit bearing capacity of the winding.

[0027] The installation process in this embodiment is as follows: Remove the upper yoke of the iron core, place the iron yoke insulation 10, put the primary winding 8 with the insulating paper tube on the secondary winding 9 with the insulating paper tube, and then put the whole assembly on the iron core column, and place the iron yoke insulation 10 and pressure plate; after stacking the upper yoke of the iron core, connect the tap lead to the non-excitation tap changer, configure the primary and secondary side leads, after vacuum drying the body, connect the body to the tank cover through screws, nuts, and flat washers, place it in the oil tank, connect the primary and secondary side leads to the bushings through the manhole of the riser seat, seal the manhole cover, hang the plate radiator, install the oil conservator, and finally inject insulating oil to complete the product assembly.

[0028] Compared to traditional prefabricated substation structures, this embodiment uses primary and secondary side leads that directly exit through the riser on the bushing side, directly connecting to the high and low voltage outgoing line cabinets, facilitating busbar connection with the switchgear. The oil conservator adopts a square capsule-type structure, effectively reducing the overall height of the transformer. The plate radiator adopts a direct-mounted type, effectively reducing the overall width of the transformer. Compared to traditional prefabricated substations, the overall structure is more compact, smaller in size, lower in cost, and lighter in weight, solving the problems of difficult transportation and troublesome on-site assembly. It also features high insulation strength and strong short-circuit withstand capability.

[0029] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements can be made without departing from the principle of the present utility model. These improvements should also be considered within the scope of protection of the present utility model without creative effort.

Claims

1. A power transformer for a box-type substation, comprising an oil conservator, an oil tank, and a finned radiator, characterized in that: The oil storage tank is a square capsule type oil storage tank, which is fixedly arranged on the top of the oil tank, the tank cover is provided with a no-field tap switch connected with the primary winding of the transformer in the oil tank through a tap lead, the front and rear ends of the oil tank are provided with a sheet type radiator in communication with the oil tank, the left and right sides of the oil tank are respectively provided with a lifting seat connected with a high voltage sleeve and a low voltage sleeve, the high voltage sleeve and the low voltage sleeve are vertically arranged and fixedly arranged outside the lifting seat, the lifting seat is in communication with the oil tank, one side of the lifting seat is provided with a hand hole and a hand hole cover plate, the primary side lead is connected with the high voltage sleeve through the lifting seat, and the secondary side lead is connected with the low voltage sleeve through the lifting seat.

2. The power transformer for a box-type substation according to claim 1, characterized by: The connection mode of the sheet type radiator and the oil tank is a straight hanging type connection.

3. The power transformer for a box-type substation according to claim 1, characterized by: The transformer body in the oil tank is connected with the tank cover through a screw rod and a nut.

4. The power transformer for use in a box-type substation according to claim 1, characterized by: The lifting seat is a square structure, circular holes are arranged at the positions where the high voltage sleeve and the low voltage sleeve are connected with the lifting seat, and sealing washers are arranged for sealing, the lifting seat is welded with a screw column for fixing the sleeve, a hand hole is arranged on one side of the lifting seat, and a hand hole flange is welded.

5. The power transformer for use in a box-type substation according to claim 1, characterized by: The primary side winding of the transformer is provided with a tap number, which is connected with the no-field tap switch through a tap lead.

6. The power transformer for use in a box-type substation according to claim 1, characterized by: The primary winding insulation paper tube and the secondary winding insulation paper tube of the transformer adopt T4 insulation hard paper tubes.

7. The power transformer for use in a box-type substation according to claim 1, characterized by: Iron yoke insulations are arranged on the upper and lower ends of the primary winding and the secondary winding of the transformer, and a pressing plate is arranged on the outer layer of the iron yoke insulation, and the outer side of the pressing plate is in contact with the inner side of the iron yoke.

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