Transformer core structure

Abstract

This invention relates to the field of transformer technology, specifically a transformer core structure, including a frame. Inside the frame, two side posts, one core post, an upper yoke, and a lower yoke are installed. The frame is equipped with an oil guiding mechanism that directly guides oil into the side posts, core post, upper yoke, and lower yoke. This invention uses an oil supply assembly to actively pump cooling oil into a rectangular oil guiding groove inside the core, allowing the cooling oil to directly contact and exchange heat with the inside of the core. Furthermore, through the oil delivery pipe, the oil first contacts the center of the inner side of the core, and then flows towards both ends along the pipeline assembly under oil pressure, achieving efficient heat dissipation from the inside to the outside of the core and ensuring the stable operation of the transformer.

Description

Technical Field

[0001] This invention relates to the field of transformer technology, specifically a transformer core structure. Background Technology

[0002] As the core equipment for energy conversion and transmission in the power system, the transformer's core is a key component. The core is usually composed of two parts: the core column and the yoke. The windings are mounted on the core column, and the yoke connects the core columns to form a closed magnetic circuit structure. The cores of existing transformers are generally made of thin silicon steel sheets with an insulating layer on the surface.

[0003] In oil-immersed transformers, the losses in the core and windings are ultimately converted into heat energy, which raises the temperature of the transformer oil. The heat is transferred to the tank wall and external radiator through thermal convection of the oil, and then dissipated into the surrounding environment. The heat dissipation capacity of the core is directly related to the transformer's load capacity, insulation life and operational reliability. Therefore, the design of the core's heat dissipation structure has always been a research focus in the field of transformer technology.

[0004] To address the aforementioned issues, existing technologies exist that guide the cooling medium into the iron core through flow-guiding structures created on silicon steel sheets. Flow-guiding grooves are created on the edge and central laminations, and flow-through grooves are created on the transverse laminations. By utilizing the combination of flow-through grooves and flow-guiding grooves, the flow of heat transfer oil within the iron core is guided, thereby achieving heat dissipation within the iron core.

[0005] However, there are still limitations in practical applications: on the one hand, its heat dissipation mechanism is a passive heat dissipation method. After the iron core heats up, it can only rely on the natural heat convection of the transformer oil to drive the flow of the cooling medium. The oil flow is slow and the heat exchange efficiency is limited. On the other hand, the cooling medium only flows unidirectionally along the iron core channel. When the oil flows through the first half, the temperature is lower and the heat exchange effect is better. However, when it flows to the second half, the oil itself has absorbed a lot of heat and the temperature rises. The temperature difference between the oil and the iron core decreases, and the driving force for further heat exchange is significantly weakened. As a result, the heat in the second half of the iron core cannot be effectively removed, and the overall heat dissipation efficiency is greatly reduced.

[0006] Therefore, how to improve the heat dissipation efficiency inside the transformer core has become an urgent technical problem to be solved. Summary of the Invention

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a transformer core structure, including a frame, inside which two side posts, one core post, an upper yoke and a lower yoke are installed. The side posts, core post, upper yoke and lower yoke are all made of several silicon steel sheets stacked together. The frame is provided with an oil guiding mechanism that directly introduces oil into the side posts, core post, upper yoke and lower yoke.

[0008] The side pillar, core pillar, upper yoke, and lower yoke are all provided with rectangular oil guide grooves. The rectangular oil guide grooves have a U-shaped structure, which allows the cooling oil to flow from inside the rectangular oil guide grooves to the front of the side pillar, core pillar, upper yoke, and lower yoke. Piping assemblies are arranged inside the rectangular oil guide grooves.

[0009] The oil guiding mechanism includes two oil supply components fixedly installed at the front of the frame and arranged symmetrically in the upper and lower parts, and an oil delivery pipe set inside the pipeline assembly. The oil delivery pipe is connected to the oil supply components at the corresponding positions and is used to directly deliver oil to the center position of the pipeline assembly.

[0010] The oil is directly supplied to the side pillars, core pillars, upper yoke, and lower yoke to cool them directly from the inside.

[0011] Preferably, the pipeline assembly consists of four support plates arranged in a rectangular tube, each support plate being composed of several stacked silicon steel sheets.

[0012] Preferably, one side of the carrier piece is provided with several protruding structures and the other side is provided with several recessed structures. The protruding structures of two adjacent carrier pieces are inserted into the recessed structures to achieve splicing of four carrier pieces.

[0013] Preferably, when the side posts, core posts, upper yoke, and lower yoke are stacked to half their height, the assembled pipeline assembly is buried inside the rectangular oil guide groove.

[0014] Preferably, the oil supply assembly includes a conduit fixedly installed on the front side of the frame, a miniature oil pump fixedly installed on the frame, and the oil outlet of the miniature oil pump is connected to the corresponding conduit.

[0015] Preferably, one end of the oil pipeline located at the front of the frame is connected to a conduit at a corresponding position.

[0016] Preferably, the oil pipeline consists of an inner L-shaped pipe and an outer oil drain cylinder. The oil drain cylinder has multiple sets of oil holes evenly spaced along its length, and the diameter of the oil holes gradually decreases from the middle of the pipeline assembly to both ends.

[0017] Preferably, two oil drain cylinders located within the same pipeline assembly are rotatably connected to a grooved cylinder at their close ends. Two propellers are fixedly installed inside the grooved cylinder, and the propellers are located inside the corresponding L-shaped pipes.

[0018] Preferably, two symmetrically arranged spiral plates are fixedly installed on the outside of the groove cylinder, the spiral plates are located outside the corresponding oil drain cylinder and the two do not contact each other.

[0019] Preferably, the oil in the L-shaped pipe drives the turbine to rotate, which in turn drives the spiral plate to rotate, thereby pushing the oil from the middle of the pipeline assembly to both ends.

[0020] The beneficial effects of this invention are as follows: First, this invention uses an oil supply assembly to actively pump cooling oil through oil pipes to rectangular oil guide grooves opened inside the side columns, core columns, upper yoke, and lower yoke, allowing the cooling oil to directly contact and exchange heat with the inside of the core, efficiently removing the heat generated during core operation; and through the guidance of the oil pipes, the oil first contacts the inner center of the side columns, core columns, upper yoke, and lower yoke, and then the oil flows to both ends along the pipeline assembly under oil pressure, finally allowing the oil to flow out of the core, achieving efficient heat dissipation of the core from the inside out, and ensuring the stable operation of the transformer.

[0021] Second, this invention uses a micro oil pump to extract low-temperature oil from the transformer and pump it into the interior of the L-shaped tube, thereby actively transporting the oil to flow and exchange heat inside the side column, core column, upper yoke and lower yoke. Compared with the traditional passive heat dissipation method that relies on natural heat convection, the oil movement speed is significantly increased and the flow rate can be controlled by adjusting the micro oil pump, which facilitates precise control of the core's operating temperature.

[0022] Third, this invention uses an L-shaped tube to directly guide the low-temperature oil to the central position of the pipeline assembly, so that most of the low-temperature oil flows out through the groove cylinder and contacts the central area of ​​the iron core for heat exchange, ensuring the heat dissipation effect of the central position inside the side column, core column, upper yoke and lower yoke. A small part of the oil flows along the inside of the oil drain cylinder to both ends of the pipeline assembly, and at the same time flows out through multiple sets of oil holes on the oil drain cylinder to contact the iron core, which also ensures the heat dissipation effect of the remaining positions inside the iron core, making the temperature distribution of each part of the iron core more uniform.

[0023] Fourth, this invention uses oil flowing out of the L-shaped pipe to actively drive the propeller to rotate slowly, so that the propeller drives the spiral plate to rotate slowly through the grooved cylinder. This allows the spiral plate to actively push the oil inside the pipeline assembly, enhancing the unidirectional flow of oil from the middle to both ends of the pipeline assembly, effectively reducing the backflow of hot oil, and further ensuring the continuous and efficient heat dissipation effect inside the iron core. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] Figure 1 This is a schematic diagram of the first overall structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the second overall structure of the present invention;

[0027] Figure 3 This is a partial exploded view of the frame, side pillars, core pillars, and piping components in this invention;

[0028] Figure 4 This is a partial cross-sectional view of the side pillar, core pillar, lower yoke, and piping assembly in this invention;

[0029] Figure 5 This is a partial cross-sectional view of the core column, lower yoke, pipeline assembly, and rectangular oil guide groove in this invention;

[0030] Figure 6 This is a partial exploded view of the carrier sheet in this invention;

[0031] Figure 7 This is a schematic diagram of the structure of the miniature oil pump, conduit, L-shaped tube and bearing plate in this invention;

[0032] Figure 8 This is a schematic diagram of the structure of the bearing plate, L-shaped tube, oil drain cylinder and spiral plate in this invention;

[0033] Figure 9 This is a partial cross-sectional view of the L-shaped pipe, the oil drain cylinder, and the trough cylinder in this invention;

[0034] Figure 10 This is a partial cross-sectional view of the L-shaped pipe, oil drain, tank, and turboprop in this invention.

[0035] In the diagram: 1. Frame; 2. Side column; 3. Core column; 4. Upper yoke; 5. Lower yoke; 6. Oil guiding mechanism; 7. Rectangular oil guiding groove; 8. Piping assembly; 61. Oil supply assembly; 62. Oil delivery pipe; 81. Bearing plate; 611. Conduit; 612. Miniature oil pump; 621. L-shaped pipe; 622. Oil drain cylinder; 623. Groove cylinder; 624. Turbine; 625. Propeller plate. Detailed Implementation

[0036] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. Where specific techniques or conditions are not specified in the embodiments, they shall be performed in accordance with the techniques or conditions described in the literature in the art or in accordance with the product manual.

[0037] See Figure 1 , Figure 2 and Figure 3 A transformer core structure includes a frame 1. Inside the frame 1, two side posts 2, a core post 3, an upper yoke 4, and a lower yoke 5 are installed. The side posts 2, core post 3, upper yoke 4, and lower yoke 5 are all made of stacked silicon steel sheets. The frame 1 is provided with an oil guiding mechanism 6 that directly guides oil into the side posts 2, core post 3, upper yoke 4, and lower yoke 5.

[0038] During operation, the transformer equipped with this core structure can actively and continuously transport the low-temperature oil inside the transformer to the interior of the side column 2, core column 3, upper yoke 4 and lower yoke 5 through the oil guiding mechanism 6. This achieves the effect of directly dissipating heat inside the core structure. At the same time, it allows the low-temperature oil to flow from the inside of the core to the outside, and finally to the inner wall of the transformer shell for heat dissipation. This achieves efficient heat dissipation of the core from the inside to the outside, ensuring the stable operation of the transformer.

[0039] See Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 Rectangular oil guide grooves 7 are provided inside the side pillar 2, core pillar 3, upper yoke 4 and lower yoke 5. The rectangular oil guide grooves 7 have a U-shaped structure, which allows the cooling oil to flow from inside the rectangular oil guide grooves 7 to the front of the side pillar 2, core pillar 3, upper yoke 4 and lower yoke 5. Pipeline assemblies 8 are arranged inside the rectangular oil guide grooves 7.

[0040] See Figure 4 , Figure 5 and Figure 6 The pipeline assembly 8 consists of four support plates 81 arranged in a rectangular tube. Each support plate 81 is made of several stacked silicon steel sheets. One side of the support plate 81 has several protruding structures, and the other side has several recessed structures.

[0041] When making the iron core, the operator stacks a certain number of silicon steel sheets of a specified shape into a support plate 81. Then, four support plates 81 are taken and vertically spliced ​​together in pairs, such that the protruding structure of one support plate 81 is inserted into the recessed structure of the other support plate 81. This process is repeated to splice the four support plates 81 into a square cylindrical structure, thereby forming the pipeline assembly 8.

[0042] After assembling the five pipe components 8, the operator begins to stack silicon steel sheets of a specified shape to create two side posts 2, one core post 3, an upper yoke 4, and a lower yoke 5. When the stacking reaches half the thickness of the final product, the operator places the pipe components 8 into the rectangular oil guide grooves 7 of the two side posts 2, one core post 3, the upper yoke 4, and the lower yoke 5 in sequence. Then, the silicon steel sheets are stacked to complete the production of the iron core. The pipe components 8 are then embedded in the rectangular oil guide grooves 7 of the iron core to increase the overall strength of the iron core and prevent the iron core's stress strength from being excessively reduced due to the presence of the rectangular oil guide grooves 7.

[0043] It should be noted that although opening holes and slots on the iron core affects the magnetic properties of the iron core and indirectly increases the heat generation of the iron core, the size of the rectangular oil guide groove 7 in this iron core structure is obtained through repeated experiments by those skilled in the art, which minimizes the additional heat generation of this iron core structure. Furthermore, the oil guide mechanism 6 provides efficient heat dissipation from the inside to the outside of the iron core, resulting in a significant decrease in the operating temperature of the iron core.

[0044] It is worth noting that the steps of stacking silicon steel sheets to make side pillars 2, core pillars 3, upper yokes 4 and lower yokes 5 in this invention are common existing technical means, so they will not be described in detail in this article. In addition, during the manufacturing process, side pillars 2, core pillars 3, upper yokes 4 and lower yokes 5 are closely fitted with their internal pipeline components 8 to form a whole.

[0045] See Figure 1 , Figure 2 , Figure 7 and Figure 8 The oil guiding mechanism 6 includes two oil supply components 61 fixedly installed at the front of the frame 1 and arranged symmetrically in the upper and lower parts, and an oil delivery pipe 62 set inside the pipeline assembly 8. The oil delivery pipe 62 is connected to the oil supply components 61 at the corresponding positions and is used to directly deliver oil to the center position of the pipeline assembly 8.

[0046] When the transformer is running, the oil supply assembly 61 actively pumps the cooling oil through the oil supply pipe 62 to the pipeline assembly 8 inside the side column 2, core column 3, upper yoke 4, and lower yoke 5, so that the cooling oil directly contacts the inside of the core for heat exchange, efficiently removing the heat generated by the core during operation. Furthermore, through the guidance of the oil supply pipe 62, the oil first contacts the inner center of the side column 2, core column 3, upper yoke 4, and lower yoke 5, and then the oil flows to both ends along the pipeline assembly 8 under oil pressure, finally allowing the oil to flow out of the core, achieving efficient heat dissipation of the core from the inside out, and ensuring the stable operation of the transformer.

[0047] To actively pump cryogenic oil into the interior of the iron core, the present invention designs the following structure: (See reference) Figure 2 , Figure 7 , Figure 8 and Figure 9 The oil supply assembly 61 includes a conduit 611 fixedly installed on the front side of the frame 1. A micro oil pump 612 is fixedly installed on the frame 1. The oil outlet of the micro oil pump 612 is connected to the corresponding conduit 611. One end of the oil supply pipe 62 located at the front of the frame 1 is connected to the conduit 611 at the corresponding position.

[0048] When the transformer is running, the micro oil pump 612 is started, which draws low-temperature oil from the transformer and pumps it into the conduit 611. Through the continuous pumping of the micro oil pump 612, the low-temperature oil moves along the conduit 611 and is distributed to each oil delivery pipe 62. Finally, the oil delivery pipe 62 directly introduces the oil into the central position inside the pipeline assembly 8.

[0049] To ensure that the low-temperature oil flowing out of the oil pipe 62 directly contacts the centrally located interior of the pipeline assembly 8, the present invention designs the following structure: (See attached diagram) Figure 7 , Figure 8 , Figure 9 and Figure 10 The oil pipeline 62 is composed of an inner L-shaped pipe 621 and an outer oil drain cylinder 622. The end of the L-shaped pipe 621 located at the front of the frame 1 is connected to the conduit 611. The two oil drain cylinders 622 located in the same pipeline assembly 8 are rotatably connected to the end of the two oil drain cylinders 622 that are close to each other.

[0050] When the transformer is running, the two L-shaped tubes 621 located in the same pipeline assembly 8 simultaneously discharge the low-temperature oil inside them into the corresponding slot cylinder 623. Under the action of the oil, most of the low-temperature oil flows outward through the slot cylinder 623, so that most of the low-temperature oil directly contacts the central position inside the pipeline assembly 8, thereby achieving cooling of the central position of the pipeline assembly 8.

[0051] Because the low-temperature oil flowing directly to the center of the pipeline assembly 8 flows towards both ends of the pipeline assembly 8 under oil pressure, this low-temperature oil gradually heats up during the flow, causing its cooling capacity to gradually decrease. Therefore, in order to delay the heating of the oil inside the pipeline assembly 8 and efficiently remove heat from the iron core, the present invention designs the following structure: (See reference) Figure 8 and Figure 9 The oil drain cylinder 622 has multiple sets of oil holes at equal intervals along its length, and the diameter of the oil holes gradually decreases from the middle of the pipeline assembly 8 to both ends.

[0052] Most of the low-temperature oil flows directly outward through the groove cylinder 623. At the same time, after the low-temperature oil moves to the middle of the groove cylinder 623, a small portion of the low-temperature oil flows in the opposite direction to the corresponding drain cylinder 622 and flows along the length of the drain cylinder 622 to both ends of the pipeline assembly 8. During the flow, this low-temperature oil gradually flows outward through the oil hole, so that this low-temperature oil mixes with the externally heated oil, effectively ensuring the heat absorption capacity of the external oil, and thus efficiently removing the heat inside the iron core.

[0053] To enhance the unidirectional flow of oil from the middle to both ends of the pipeline assembly 8 and effectively reduce hot oil backflow, the present invention designs the following structure: (See attached diagram) Figure 8 , Figure 9 and Figure 10 Two turboprops 624 are fixedly installed inside the trough 623. The turboprops 624 are located inside the corresponding L-shaped tube 621. Two symmetrically arranged spiral plates 625 are fixedly installed on the outside of the trough 623. The spiral plates 625 are located outside the corresponding oil drain 622 and the two do not contact each other.

[0054] When the transformer is running, the oil flowing out of the L-shaped tube 621 actively drives the turbine 624 to rotate slowly, which in turn drives the spiral plate 625 to rotate slowly through the slotted cylinder 623. This allows the spiral plate 625 to actively push the oil inside the pipeline assembly 8, further ensuring the continuous and efficient heat dissipation effect inside the iron core.

[0055] Although this invention adds pipeline components 8, oil supply pipes 62, L-shaped pipes 621, and oil drain cylinders 622 to the traditional iron core structure, and creates rectangular oil guide grooves 7 inside the side pillars 2, core pillars 3, upper yoke 4, and lower yoke 5, thus increasing the manufacturing process of the iron core and slightly raising the initial investment cost, the active pumping of the oil supply components 61 and the oil supply pipes 62 enables forced convection heat exchange of the cooling oil from the center of the iron core to both ends and from the inside to the outside. This significantly reduces the operating temperature of the iron core, effectively improving the transformer's load capacity and insulation life, and reducing the risk of failure and maintenance costs caused by overheating. From the perspective of the overall life cycle operation benefits of the equipment, the increased costs in the early stage can be quickly balanced in a short period of time through improved operational reliability and reduced losses, demonstrating significant economic and engineering practical value.

[0056] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0057] Furthermore, the terms "first," "second," "number one," and "number two" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," "number one," or "number two" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0058] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0059] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made based on the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A transformer core structure, characterized in that, The frame includes two side columns, one core column, an upper yoke, and a lower yoke. The side columns, core column, upper yoke, and lower yoke are all made of stacked silicon steel sheets. The frame is equipped with an oil guiding mechanism that directly guides oil into the side columns, core column, upper yoke, and lower yoke. The side pillar, core pillar, upper yoke, and lower yoke are all provided with rectangular oil guide grooves. The rectangular oil guide grooves have a U-shaped structure, which allows the cooling oil to flow from inside the rectangular oil guide grooves to the front of the side pillar, core pillar, upper yoke, and lower yoke. Pipeline components are arranged inside the rectangular oil guide grooves. The oil guiding mechanism includes two oil supply components fixedly installed at the front of the frame and arranged symmetrically in the upper and lower parts, and an oil delivery pipe set inside the pipeline assembly. The oil delivery pipe is connected to the oil supply components at the corresponding positions and is used to directly deliver oil to the center position of the pipeline assembly. The oil is directly supplied to the side pillars, core pillars, upper yoke, and lower yoke to cool them directly from the inside.

2. The transformer core structure according to claim 1, characterized in that, The pipeline assembly consists of four support plates arranged in a rectangular tube, each of which is made up of several stacked silicon steel sheets.

3. A transformer core structure according to claim 2, characterized in that, The support plate has several protruding structures on one side and several recessed structures on the other side. The protruding structures of two adjacent support plates are inserted into the recessed structures to achieve splicing of the four support plates.

4. A transformer core structure according to claim 1, characterized in that, When the side posts, core posts, upper yoke and lower yoke are stacked to half the height, the assembled pipeline assembly is buried inside the rectangular oil guide groove.

5. A transformer core structure according to claim 1, characterized in that, The oil supply assembly includes a conduit fixedly installed on the front side of the frame, and a miniature oil pump is fixedly installed on the frame. The oil outlet of the miniature oil pump is connected to the corresponding conduit.

6. A transformer core structure according to claim 5, characterized in that, The oil pipeline is connected to the corresponding conduit at one end of the front of the frame.

7. A transformer core structure according to claim 1, characterized in that, The oil pipeline consists of an inner L-shaped pipe and an outer drain cylinder. The drain cylinder has multiple sets of oil holes at equal intervals along its length, and the diameter of the oil holes gradually decreases from the middle of the pipeline assembly to both ends.

8. A transformer core structure according to claim 7, characterized in that, Two oil drain cylinders located within the same piping assembly are rotatably connected to a grooved cylinder at their close ends. Two propellers are fixedly installed inside the grooved cylinder, and the propellers are located inside the corresponding L-shaped pipes.

9. A transformer core structure according to claim 8, characterized in that, Two symmetrically arranged spiral plates are fixedly installed on the outside of the groove cylinder. The spiral plates are located outside the corresponding oil drain cylinder and the two do not contact each other.

10. A transformer core structure according to claim 9, characterized in that, The oil inside the L-shaped pipe drives the propeller to rotate the tank, which in turn drives the spiral plate to rotate, thereby pushing the oil from the middle of the pipeline assembly to both ends.

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