A combined transformer

Abstract

This invention relates to the field of prefabricated transformer technology and discloses a combined transformer, including a transformer welded to the top of a distribution cabinet, having a three-phase high-voltage terminal and a four-phase low-voltage output terminal; the three-phase high-voltage terminal serves as a high-voltage side access port for connecting to a high-voltage transmission line; the transformer steps down the high-voltage electricity to low-voltage electricity, which is then led out through the four-phase low-voltage output terminal and electrically interconnected with the feeder switch inside the distribution cabinet via copper busbars, ensuring stable conduction of the low-voltage distribution circuit; this invention adopts an integrated design of the transformer and distribution cabinet, abandoning the traditional independent arrangement mode of prefabricated transformer modules, reducing horizontal space occupation, and overcoming assembly limitations in space-constrained areas; coupled with a horizontally placed heat dissipation component, it solves the problems of poor compatibility between traditional vertical heat sinks and natural wind direction, and obstructed internal ventilation; through horizontal arrangement and efficient adaptation to horizontal wind direction, it ensures smooth airflow through the heat dissipation channel, achieving full heat exchange of all heat sinks.

Description

Technical Field

[0001] This invention relates to the field of transformer substation technology, and in particular to a combined transformer. Background Technology

[0002] A prefabricated substation is a compact set of power distribution equipment that combines high-voltage switchgear, distribution transformers, and low-voltage power distribution devices. It is widely used in urban and rural power supply. Currently, the American and European styles are the most commonly used. In the structural design of American and European prefabricated transformers, the high-voltage equipment, transformers, and low-voltage equipment are mostly arranged in relatively independent modules. A certain amount of space needs to be reserved between each module for operation and heat dissipation, which makes it difficult to compress the overall size. However, due to space limitations in some assembly areas, it is not possible to assemble large-volume American and European-style prefabricated transformers. Meanwhile, existing transformer substation heat sinks are vertically arranged to ensure even contact with the upper and lower cooling oil layers. The air passage between two adjacent heat sinks is also vertical. Without additional fan installation, natural airflow has difficulty entering the air passage, thus affecting the heat dissipation effect. Summary of the Invention

[0003] In view of the problems existing in the current combined transformer, the present invention is proposed.

[0004] The above-mentioned technical problems are solved by the following technical solution: This invention proposes a combined transformer, comprising, The transformer is welded to the top of the distribution cabinet and has three-phase high-voltage terminals and four-phase low-voltage output terminals. The three-phase high-voltage terminal serves as the high-voltage side access port for connecting to the high-voltage transmission line. After the transformer steps down the high-voltage electricity to convert it into low-voltage electricity, it is led out through the four-phase low-voltage output terminal and electrically interconnected with the feeder switch inside the distribution cabinet through the copper busbar to ensure the stable conduction of the low-voltage distribution circuit.

[0005] In a preferred embodiment of the combined transformer of the present invention: the transformer is provided with a heat dissipation component to suppress the temperature rise caused by copper loss and iron loss during transformer operation; The heat dissipation component is mounted horizontally on one side of the transformer to improve the heat exchange efficiency inside the transformer.

[0006] In a preferred embodiment of the combined transformer of the present invention: the heat dissipation assembly includes a plurality of heat sinks and four converter tubes; The heat sink is arranged horizontally, with its length direction extending along the X-axis, and several of the heat sinks are distributed in an equidistant array along the Y-axis. One side of the heat sink extends through the transformer and into its interior, contacting the cooling oil inside the transformer. A transverse heat dissipation channel is formed between two adjacent heat sinks for airflow to carry away the heat on the heat sink. The four converter tubes are arranged symmetrically in pairs and vertically at both ends of the heat sink. Both ends of the four converter tubes penetrate the transformer and are connected to its interior, forming an upper / lower oil circulation loop. The oil exchange is achieved through the natural convection of hot and cold oil, further improving the heat dissipation efficiency.

[0007] In a preferred embodiment of the combined transformer of the present invention: the distribution cabinet has a low-voltage reactive power compensation capacitor bank; The low-voltage reactive power compensation capacitor bank is mounted in the distribution cabinet via a mounting base. The mounting base can be horizontally displaced along the X-axis, moving the low-voltage reactive power compensation capacitor bank out of the distribution cabinet for maintenance.

[0008] In a preferred embodiment of the combined transformer of the present invention: a cabinet door is provided on one side of the distribution cabinet at the position corresponding to the mounting base.

[0009] In a preferred embodiment of the combined transformer of the present invention, a protective part is further included, which covers the outside of the combined transformer to prevent direct sunlight from causing the transformer temperature to be too high, resulting in accelerated insulation aging, local overheating, or even burnout.

[0010] In a preferred embodiment of the combined transformer of the present invention: the protective part includes a frame, the four sides of the frame are equipped with protective plates, and the top of the frame is covered with a top cover.

[0011] In a preferred embodiment of the combined transformer of the present invention: both the protective plate and the top cover are made of SMC material, and both the protective plate and the top cover are assembled onto the frame by rivets.

[0012] In a preferred embodiment of the combined transformer of the present invention: heat dissipation holes are symmetrically provided on the protective plate near both ends of the heat sink, and the heat dissipation holes are connected to the heat dissipation channel for airflow. A second heat dissipation hole is provided on the protective plate near the outer side of the heat sink, and the length of the second heat dissipation hole is equal to the length of the heat sink.

[0013] In a preferred embodiment of the combined transformer of the present invention: the protective plate is provided with an outer door at the positions corresponding to the high and low voltage sides of the transformer and the cabinet door of the distribution cabinet.

[0014] The beneficial effects of this invention are as follows: This invention welds the transformer to the top of the distribution cabinet to form an integrated structural design, abandoning the traditional method of independently arranging each module of the box-type transformer, reducing the horizontal space occupation, breaking through the assembly limitations in space-constrained areas, and solving the problems of poor compatibility between traditional vertical heat sinks and natural wind direction and obstructed ventilation of the inner heat sinks. By arranging the heat sinks horizontally, it forms an efficient fit with the natural horizontal wind direction, allowing airflow to pass through all heat dissipation channels without obstruction, ensuring that all heat sinks can fully contact the air for heat exchange, and greatly improving the heat dissipation efficiency on the air side. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein: Figure 1 A three-dimensional structural diagram of a combined transformer is shown; Figure 2 A rear view structural diagram of a combined transformer is shown; Figure 3 A structural diagram of the heat dissipation assembly in a combined transformer is shown; Figure 4 A structural diagram of the protection section in a combined transformer is shown; Figure 5 A disassembled structural diagram of the protection section in a combined transformer is shown. Detailed Implementation

[0016] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0017] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0018] It should be noted that a prefabricated substation is a compact set of power distribution equipment that combines high-voltage switchgear, distribution transformers, and low-voltage power distribution devices. It is widely used in urban and rural power supply. Currently, the American and European styles are the most commonly used. In the structural design of American and European prefabricated transformers, the high-voltage equipment, transformers, and low-voltage equipment are mostly arranged in relatively independent modules. A certain amount of space needs to be reserved between each module for operation and heat dissipation, which makes it difficult to compress the overall size. However, due to space limitations in some assembly areas, it is not possible to assemble large-volume American and European-style prefabricated transformers.

[0019] Reference Figure 1 This embodiment provides a combined transformer, including, Transformer 1 is welded to the top of distribution cabinet 2 to form an integrated structure, which has the advantages of compact structure and small size, and solves the problem of large size and space limitation of traditional European and American transformers. Transformer 1 has a three-phase high-voltage terminal 11 and a four-phase low-voltage output terminal 12; The three-phase high-voltage terminal 11 serves as the high-voltage side access port, used to connect to 10kV and above high-voltage transmission lines. After the transformer 1 completes the voltage reduction conversion from high-voltage to low-voltage power through the principle of electromagnetic induction, the power is led out through the four-phase low-voltage output terminal 12 and electrically interconnected with the feeder switch inside the distribution cabinet 2 through the copper busbar 3, thus constructing a stable low-voltage power distribution circuit, ensuring that low-voltage power is accurately delivered to end users, and combining power transmission efficiency and power distribution safety protection functions.

[0020] This design adopts an integrated structure with upper and lower integrated welding, abandoning the traditional method of arranging each module of the box-type transformer independently. It utilizes vertical space superposition to optimize the equipment layout, reduce the horizontal space occupation, and ensures structural stability through welding fixation. It breaks through the assembly limitations in space-constrained areas and provides convenience for power assembly in narrow spaces (such as dense urban transformer areas and old residential area power distribution rooms).

[0021] Distribution cabinet 2 contains a low-voltage reactive power compensation capacitor bank 21. After the low-voltage electrical energy output from transformer 1 enters distribution cabinet 2, when reactive power loss occurs in the distribution circuit, the low-voltage reactive power compensation capacitor bank 21 automatically starts to operate. It compensates for the reactive power in the circuit through the charging and discharging characteristics of the capacitor, thereby reducing power factor loss. When the reactive power in the circuit is within a reasonable range, the capacitor bank automatically stops operating, completing one round of reactive power compensation adjustment and continuously ensuring the power balance of the distribution circuit. The low-voltage reactive power compensation capacitor bank 21 is mounted in the distribution cabinet 2 via the mounting base 22. The mounting base 22 can be horizontally displaced along the X-axis, which can move the low-voltage reactive power compensation capacitor bank 21 out of the distribution cabinet 2 for maintenance.

[0022] Specifically, the mounting base 22 is mounted in the distribution cabinet 2 via a track. The track adopts a symmetrical "concave" structure, and the mounting base 22 is a flat plate structure. The thickness of the flat plate is adapted to the groove of the "concave" structure of the track, so it can slide along the direction of the groove. When the capacitor bank needs to be repaired, the mounting base 22 is pushed to move horizontally along the X-axis, which drives the low-voltage reactive power compensation capacitor bank 21 to move out of the distribution cabinet 2 at the same time. After the maintenance is completed, the mounting base 22 is pushed in the opposite direction to move the low-voltage reactive power compensation capacitor bank 21 back to the working position inside the distribution cabinet 2 and fix it, thus completing the maintenance work. A cabinet door 23 is provided on one side of the distribution cabinet 2 at the position corresponding to the mounting base 22.

[0023] The design facilitates the removal of the low-voltage reactive power compensation capacitor bank 21 from the distribution cabinet 2 via the sliding mounting base 22 and cabinet door 23, making it easier for maintenance personnel to perform maintenance.

[0024] As an optional embodiment: It should be noted that traditional European and American converters use vertically mounted heat sinks. The length of the vertically mounted heat sinks can reach different depths of cooling oil, so that both the upper and lower layers of cooling oil can be cooled by heat exchange. However, when the heat sink is set vertically, several heat sinks can only be arranged in a horizontal direction. Therefore, the channel between two adjacent heat sinks is vertical, while the natural wind direction is mostly horizontal. As a result, the horizontal wind is blocked after hitting the outermost heat sink and cannot enter the vertical channel. Therefore, the inner heat sinks cannot get airflow, resulting in poor heat dissipation.

[0025] Reference Figure 2-3 In one embodiment provided in this application, a heat dissipation component 4 is provided on the transformer 1 to suppress the temperature rise caused by copper loss and iron loss during the operation of the transformer 1; The heat dissipation component 4 is mounted horizontally on one side of the transformer 1 to improve the heat exchange efficiency inside the transformer 1.

[0026] The heat dissipation component 4 includes several heat sinks 41 and four converter pipes 42; The heat sink 41 is arranged horizontally, with its length direction extending along the X-axis, and several heat sinks 41 are distributed in an equidistant array along the Y-axis. One side of the heat sink 41 extends through the transformer 1 into its interior and comes into contact with the cooling oil inside the transformer 1. A transverse heat dissipation channel is formed between two adjacent heat sinks 41 for airflow to carry away the heat on the heat sink 41. Specifically, after the cooling oil inside transformer 1 absorbs the heat generated by copper loss and iron loss, it comes into contact with the heat sink 41 that runs through the interior, and conducts the heat to the heat sink 41. Natural wind can directly enter the transverse heat dissipation channel formed between adjacent heat sinks 41. The airflow flows smoothly in the transverse channel, carrying away the heat on the heat sink 41 and achieving heat dissipation. Four converter tubes 42 are arranged symmetrically in pairs and vertically positioned at both ends of the heat sink 41. Both ends of the four converter tubes 42 penetrate the transformer 1 and connect to its interior, forming an upper / lower oil circulation loop. The oil exchange is achieved through the natural convection of hot and cold oil, further improving the heat dissipation efficiency.

[0027] Specifically, there is cooling oil in transformer 1. The upper layer of cooling oil absorbs the heat from the operation of transformer 1, and its temperature rises. The lower layer of cooling oil does not directly absorb the core heat and its temperature is lower. At this time, there is a significant temperature difference between the upper and lower layers of oil. As the temperature rises, the upper layer of cooling oil undergoes more intense molecular thermal motion, resulting in a lower oil density. The lower layer of cold oil, with its lower temperature and higher density, is naturally driven by the principle of fluid mechanics. According to this principle, fluids with lower density will move upward due to buoyancy, while fluids with higher density will sink due to gravity. Since the converter tube 42 connects the upper and lower layers of cooling oil respectively, forming a clear flow channel, the upper hot oil, due to its low density and buoyancy, will actively flow downwards and flow into the lower area along the converter tube 42. Meanwhile, the lower cold oil, due to its high density and gravity, will settle. At the same time, after the upper hot oil flows away, a slight negative pressure will be formed in the upper layer, pushing the lower cold oil to move upwards along the converter tube 42 to replenish the upper area, thus forming a closed natural circulation loop. During the circulation, after the upper hot oil flows to the lower layer, it will mix with the cold oil and cool down; after the lower cold oil replenishes the upper layer, it will absorb heat from the transformer 1 again and heat up, continuously repeating the cycle of heating up, sinking, cooling down, and rising.

[0028] This design solves the problems of poor compatibility between traditional vertical heat sinks and natural wind direction, and obstructed ventilation of the inner heat sinks. By arranging the heat sinks horizontally, it forms an efficient fit with the natural horizontal wind direction, allowing airflow to pass through all heat dissipation channels without obstruction. This ensures that all heat sinks can fully contact the air for heat exchange, greatly improving the heat dissipation efficiency on the air side. Meanwhile, the natural circulation loop of the upper / lower oil layer constructed by the converter tube 42 enhances the convective heat transfer capacity of the cooling oil inside the transformer 1. Compared with the traditional design, this design does not require additional power equipment such as fans and oil pumps. It can achieve efficient heat dissipation by relying solely on natural wind and natural oil convection. This not only reduces equipment energy consumption and subsequent maintenance costs, but also improves the stability and reliability of the heat dissipation system. It can more stably suppress the temperature rise of the transformer during operation and ensure the long-term safe and efficient operation of the transformer.

[0029] As an optional embodiment: Reference Figure 4-5 In one embodiment provided in this application, a protective part 5 is also included. The protective part 5 covers the outside of the combined transformer to prevent the transformer 1 from overheating due to direct sunlight, which may cause accelerated insulation aging, local overheating, or even burnout. It is used to avoid the transformer overheating and a series of safety hazards caused by direct sunlight, delay insulation aging, and ensure the service life of the equipment.

[0030] The protective part 5 includes a frame 51, with protective plates 52 mounted on all four sides of the frame 51, and a top cover 53 covering the top of the frame 51. Both the protective plates 52 and the top cover 53 are made of SMC material, and both the protective plates 52 and the top cover 53 are mounted on the frame 51 by rivets. SMC material has excellent heat insulation, insulation, anti-aging and flame retardant properties, which can enhance the protective effect and adapt to harsh environments.

[0031] Symmetrical heat dissipation holes 54 are provided on the protective plates 52 near both ends of the heat sink 41. The heat dissipation holes 54 are connected to the heat dissipation channel for airflow. Heat dissipation holes 55 are provided on the protective plates 52 near the outer side of the heat sink 41. The length of the heat dissipation holes 55 is equal to the length of the heat sink 41. Through the connection design between the heat dissipation holes 54 and the heat dissipation channel, and in conjunction with the heat dissipation holes 55, a smooth airflow circulation path is constructed to ensure that the heat dissipation efficiency of the heat dissipation component 4 is not affected.

[0032] The protective plate 52 is equipped with an outer door at the high and low voltage sides of transformer 1 and the cabinet door 23 of distribution cabinet 2, which facilitates the maintenance of relevant parts by staff.

[0033] This design effectively avoids the problem of excessive temperature of transformer 1 caused by direct sunlight, thereby solving the safety hazards of accelerated insulation aging, local overheating or even burnout, delaying equipment aging, and ensuring the service life of transformer 1.

[0034] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A combined transformer, characterized in that: include, The transformer (1) is welded above the distribution cabinet (2) and has a three-phase high-voltage terminal (11) and a four-phase low-voltage terminal (12). The three-phase high-voltage terminal (11) serves as the high-voltage side access port for connecting to the high-voltage transmission line. After the transformer (1) reduces the high-voltage electricity to low-voltage electricity, it is led out through the four-phase low-voltage output terminal (12) and electrically interconnected with the feeder switch inside the distribution cabinet (2) through the copper busbar (3) to ensure the stable conduction of the low-voltage distribution circuit.

2. The combined transformer according to claim 1, characterized in that: The transformer (1) is equipped with a heat dissipation component (4) to suppress the temperature rise caused by copper loss and iron loss during the operation of the transformer (1); The heat dissipation component (4) is mounted horizontally on one side of the transformer (1) to improve the heat exchange efficiency inside the transformer (1).

3. The combined transformer according to claim 2, characterized in that: The heat dissipation assembly (4) includes several heat sinks (41) and four converter tubes (42). The heat sink (41) is arranged horizontally, with its length direction extending along the X-axis, and several of the heat sinks (41) are distributed in an equidistant array along the Y-axis; One side of the heat sink (41) extends through the transformer (1) into its interior and contacts the cooling oil inside the transformer (1). A transverse heat dissipation channel is formed between two adjacent heat sinks (41) for airflow to carry away the heat on the heat sink (41). The four converter tubes (42) are arranged symmetrically in pairs and vertically set at both ends of the heat sink (41). Both ends of the four converter tubes (42) pass through the transformer (1) and are connected to its interior to form an upper / lower oil circulation loop. The oil exchange is achieved through the natural convection of hot and cold oil, which further improves the heat dissipation efficiency.

4. The combined transformer according to claim 3, characterized in that: The distribution cabinet (2) contains a low-voltage reactive power compensation capacitor bank (21). The low-voltage reactive power compensation capacitor bank (21) is mounted in the distribution cabinet (2) via a mounting base (22). The mounting base (22) can be horizontally displaced along the X-axis to move the low-voltage reactive power compensation capacitor bank (21) out of the distribution cabinet (2) for maintenance.

5. The combined transformer according to claim 4, characterized in that: The distribution cabinet (2) has a cabinet door (23) on one side corresponding to the mounting base (22).

6. The combined transformer according to claim 5, characterized in that: It also includes a protective part (5), which covers the outside of the combined transformer to prevent the transformer (1) from overheating due to direct sunlight, which could lead to accelerated insulation aging, local overheating, or even burnout.

7. The combined transformer according to claim 6, characterized in that: The protective part (5) includes a frame (51), which is equipped with protective plates (52) on all four sides and a top cover (53) on the top of the frame (51).

8. The combined transformer according to claim 7, characterized in that: Both the protective plate (52) and the top cover (53) are made of SMC material, and both the protective plate (52) and the top cover (53) are assembled onto the frame (51) by rivets.

9. The combined transformer according to claim 8, characterized in that: The protective plate (52) near both ends of the heat sink (41) is provided with symmetrical heat dissipation holes (54), which are connected to the heat dissipation channel for airflow. A second heat dissipation hole (55) is provided on the protective plate (52) near the outside of the heat sink (41), and the length of the second heat dissipation hole (55) is equal to the length of the heat sink (41).

10. The combined transformer according to claim 9, characterized in that: The protective plate (52) is provided with an outer door (56) at the high and low voltage sides of the transformer (1) and the cabinet door (23) of the distribution cabinet (2).

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