An oil-immersed transformer with an oil circulation system

Abstract

This invention relates to an oil-immersed transformer with an oil circulation system, comprising a transformer body and heat dissipation fins fixed to the surface of the transformer body, with a circulation tank disposed on the side of the transformer body; this invention relates to the field of oil-immersed transformer technology. This oil-immersed transformer with an oil circulation system, through non-contact drive, elastic sealing, and pressure self-balancing design, completely solves the persistent leakage problem of traditional oil-immersed transformer circulation pumps, and combines the advantages of high reliability, low maintenance cost, and long service life, making it particularly suitable for power equipment applications in high-temperature, high-humidity, or corrosive environments.

Description

Technical Field

[0001] This invention relates to the field of oil-immersed transformer technology, specifically to an oil-immersed transformer with an oil circulation system. Background Technology

[0002] Traditional oil-immersed transformers rely heavily on mechanical pumps for their oil circulation systems. The core problem lies in the direct contact between the drive components and the oil, leading to the following potential hazards:

[0003] Risk of seal failure:

[0004] Oil corrosivity: Transformer oil will oxidize and generate acidic substances during long-term operation, which will corrode pump body seals (such as rubber rings and mechanical seals) and lead to a decrease in sealing performance.

[0005] Thermal stress effects: Fluctuations in oil temperature (-40℃ to 100℃) cause thermal expansion and contraction of sealing materials, accelerating aging and cracking;

[0006] Mechanical wear: Long-term friction between the pump shaft and the seals creates gaps, making oil leakage unavoidable and requiring frequent shutdowns to replace the sealing components.

[0007] The consequences of a leak are serious:

[0008] Deterioration of insulation performance: Oil leakage causes the oil level inside the transformer to drop, exposing the windings to air and increasing the risk of partial discharge;

[0009] Environmental pollution: The leaked oil contains toxic polychlorinated biphenyls (PCBs) or mineral oil, polluting soil and water sources;

[0010] High maintenance costs: Traditional pumps require complete disassembly and repair after leakage, including replacement of oil and seals, which is time-consuming and labor-intensive.

[0011] Limitations of circulating pumps:

[0012] Complex structure: The built-in pump requires the motor and transmission components to be arranged inside the transformer oil tank, which takes up space and makes heat dissipation difficult;

[0013] Low energy efficiency: Mechanical pumps consume a lot of energy when running continuously, and the pumping efficiency fluctuates greatly when the oil viscosity changes with temperature.

[0014] Oil filtration affects normal operation:

[0015] Over-filtration: Normal oil needs to be filtered through a filter screen during use, even if the amount of flocculent matter in the oil does not affect normal use, it affects the normal oil circulation flow rate. Summary of the Invention

[0016] To address the shortcomings of existing technologies, this invention provides an oil-immersed transformer with an oil circulation system, which solves the aforementioned problems.

[0017] To achieve the above objectives, the present invention is implemented through the following technical solution: an oil-immersed transformer with an oil circulation system, comprising a transformer body and heat dissipation fins fixed on the surface of the transformer body, wherein a circulation box is provided on the side of the transformer body;

[0018] The inner cavity of the circulation box is equipped with a circulation mechanism for circulating the oil inside the transformer body.

[0019] The circulation mechanism includes a connecting plate that slides within the circulation tank cavity and a filter cylinder that is fixed within the circulation tank cavity. A cylinder is fixedly connected to one side of the connecting plate. The left end of the cylinder is connected to the inner cavity of the transformer body through an elastic air bladder ring. The inner cavity of the cylinder is connected to the inner cavity of the filter cylinder through a telescopic pipe. The left end of the filter cylinder is connected to the inner cavity of the transformer body through a one-way output pipe. The inner cavity of the filter cylinder contains a filter structure for filtering impurities in the oil.

[0020] The inner cavity of the circulation box is provided with a drive mechanism for driving the connecting plate of the circulation mechanism left and right.

[0021] As a further aspect of the present invention: the driving mechanism includes a driving shaft that is driven to rotate within the circulation tank cavity by a motor. An abutment wheel that abuts against the side of the connecting plate is fixedly connected to the surface of the driving shaft. Both sides of the abutment wheel have concave surfaces. A reset airbag that is fixedly connected to the inner wall of the circulation tank is fixedly connected to the right side of the connecting plate. The inner cavity of the reset airbag is connected to the inner cavity of the elastic airbag ring through a pipe. An elastic telescopic rod is fixedly connected to the side wall of the transformer body located within the circulation tank cavity. The telescopic end of the elastic telescopic rod is fixedly connected to the left side of the connecting plate.

[0022] As a further aspect of the present invention: two reset airbags are provided and are symmetrically arranged above and below the abutment wheel. By providing two reset airbags, when the elastic airbag ring is squeezed by the connecting plate and moves left and right, the pressure can be transferred to the reset airbag through the oil, thereby reducing the direct impact on the elastic airbag ring and extending its service life in the long-term extension and contraction state.

[0023] As a further aspect of the present invention: the filtration structure includes a filter baffle and an adsorption frame fixed inside the filter cylinder. The right end of the filter baffle is bent downward to wrap around the adsorption frame. There is a gap between the right end of the adsorption frame and the top of the filter cylinder. The adsorption frame is a cylindrical tube with multiple adsorption tubes on its surface. During use, under pressure fluctuations, because the impurities inside the oil are heavy, when the oil circulates and oscillates inside the filter cylinder, some of the oil containing flocculent oxides will sink below the filter baffle. Then, the flocculent oxides inside are blocked and adsorbed by the adsorption frame, and the oil is filtered upward, which can continuously filter the oil.

[0024] As a further aspect of the present invention: the bottom of the filter cartridge is threadedly connected to a threaded cylinder, the bottom of which extends through and to the outside of the circulation tank. By setting the threaded cylinder, when a certain amount of internal oxides are collected, the valves of the telescopic pipe and the one-way output pipe are closed. Under the action of gravity, the large amount of impurities accumulated in the filter cartridge can be discharged by opening the threaded cylinder. There is no need to replace all the oil; only the oil containing impurities needs to be discharged periodically, which greatly reduces the circulation cost. Only a small amount of oil needs to be added.

[0025] As a further aspect of the present invention: the bottom of the filter cylinder is provided with a first recessed section and a second recessed section respectively. The connection between the first recessed section and the second recessed section is located directly below the bend at the right end of the filter baffle. By setting the first recessed section and the second recessed section, the oil containing oxides can enter the filter cylinder more smoothly and prevent it from flowing out.

[0026] As a further aspect of the present invention: one end of the drive shaft extends through and to the outside of the circulation box, and a baffle plate is fixedly connected to the surface of the drive shaft on the outside of the circulation box. When the drive shaft rotates, it drives the baffle plate to rotate and blow air onto the heat dissipation fins to assist the internal transformer oil in heat dissipation.

[0027] As a further aspect of the present invention: a water collection tank with an opening at the top is fixedly connected to the surface of the transformer body. A drainage pipe is connected to the bottom of the water collection tank and is positioned between the baffle plate and the heat dissipation fins. When the internal oil temperature of the transformer body becomes too high, the drive motor starts, driving the drive shaft to rotate and causing the abutment wheel to rotate. As the abutment wheel rotates, it continuously abuts against the connecting plate. Due to the concave surface, the connecting plate can drive the cylinder to the left, continuously squeezing the elastic airbag ring. During this process, the oil inside the transformer body can be continuously circulated. Because of the unidirectional output pipe, a transformer body-elastic airbag ring-circle... The circulation path from the cylinder to the telescopic pipe, filter cylinder, unidirectional output pipe, and transformer body drives the oil flow, effectively dissipating heat while filtering the oil using the filtration structure. It can also cope with the thermal expansion and contraction of the oil under high and low temperatures. While applying circulation, the power component of the drive unit does not come into contact with the oil inside the transformer body, maintaining an effective sealed environment and ensuring effective circulation. When the drive shaft rotates, the valve of the drain pipe automatically opens, and the rainwater collected inside the water tank falls down and is blown onto the surface of the heat dissipation fins by the wind force of the baffle, which can effectively dissipate heat. A single drive component can achieve multiple functions.

[0028] As a further aspect of the present invention: the elastic airbag ring adopts a multi-layer composite structure, with an inner layer of oil-resistant fluororubber, a middle layer of aramid fiber reinforced mesh, and an outer layer of weather-resistant silicone coating.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] 1. In this invention, the drive mechanism is completely isolated from the oil, and the power transmission is external: the drive shaft and the abutment wheel are located in independent cavities of the circulation box and have no direct contact with the oil; the power is transmitted through the mechanical extrusion connecting plate, eliminating the need for a rotating shaft that passes through the oil cavity, thus eliminating shaft seal leakage points, and elastic elements replace rigid seals: the circulation power is achieved by the expansion and contraction deformation of the elastic airbag ring, which is made of oil-resistant fluororubber material and only withstands periodic compression rather than continuous friction, increasing its lifespan by more than 3 times; the reset airbag and the elastic telescopic rod form a two-way buffer to absorb oil pressure fluctuations and prevent the airbag ring from overload and rupture.

[0031] 2. Zero dynamic sealing requirements, static sealing advantages: The cylinder and the circulation box are connected through a fixed interface, using welding or flange static sealing. There are no moving parts, and the probability of leakage is close to zero; the filter cylinder and the threaded cylinder are connected by a threaded static connection, which only needs to be manually tightened periodically to ensure sealing.

[0032] 3. Wear-free design: When the drive shaft rotates, the contact wheel and the connecting plate are in rolling contact, resulting in minimal frictional resistance and no wear debris contaminating the oil during long-term operation.

[0033] 4. When the oil expands thermally, the elastic airbag ring expands under pressure. Excess pressure is released through the elastic deformation of the reset airbag, keeping the internal pressure of the system constant. The reset airbag works in conjunction with the elastic telescopic rod to absorb the pressure shock caused by changes in oil volume, thus avoiding system overload and extending the life of the elastic airbag ring.

[0034] 5. The drive shaft is linked to the rotation of the spoiler, which enhances the airflow on the surface of the heat dissipation fins; the water collection tank collects rainwater, which drips through the drainage pipe and is then atomized and sprayed onto the heat dissipation fins by the wind force of the spoiler, significantly improving the heat dissipation efficiency.

[0035] 6. Due to pressure fluctuations, the oil in the filter cartridge separates into layers. The flocculent oxides sink to the bottom of the filter baffle and are intercepted by the adsorption frame. The clean oil flows back through the top gap.

[0036] 7. Segmented slag discharge design: The bottom of the filter cylinder is equipped with a first and a second concave section to guide impurities to gather at the threaded cylinder. The threaded cylinder can be unscrewed periodically to discharge impurities without the need for a complete oil change, reducing maintenance costs. The drive shaft simultaneously drives the oil circulation, the baffle plate for heat dissipation, and the opening and closing of the drain valve, simplifying the structure and reducing energy consumption. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of the present invention;

[0038] Figure 2 This is a cross-sectional view of the circulation box of the present invention;

[0039] Figure 3 For the present invention Figure 2 A magnified view of a section at point A in the middle;

[0040] Figure 4 This is a side view of the structure of the circulation box of the present invention.

[0041] In the diagram: 1. Transformer body; 2. Circulation box; 3. Elastic airbag ring; 4. Cylinder; 5. Connecting plate; 6. Drive shaft; 7. Abutment wheel; 8. Concave surface; 9. Reset airbag; 10. Elastic telescopic rod; 11. Telescopic pipe; 12. One-way output pipe pressure regulator; 13. Filter cylinder; 14. Filter baffle; 15. Adsorption frame; 16. First concave section; 17. Second concave section; 18. Threaded cylinder; 19. Water collection tank; 20. Drainage pipe; 22. Heat dissipation fins. Detailed Implementation

[0042] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0043] Please see Figures 1-4 The present invention provides a technical solution: an oil-immersed transformer with an oil circulation system, including a transformer body 1 and heat dissipation fins 22 fixed on the surface of the transformer body 1, and a circulation box 2 is provided on the side of the transformer body 1.

[0044] The inner cavity of the circulation box 2 is equipped with a circulation mechanism for circulating the oil inside the transformer body 1.

[0045] The circulation mechanism includes a connecting plate 5 slidably disposed within the inner cavity of the circulation tank 2 and a filter cylinder 13 fixed within the inner cavity of the circulation tank 2. A cylinder 4 is fixedly connected to one side of the connecting plate 5. The left end of the cylinder 4 is connected to the inner cavity of the transformer body 1 via an elastic air bladder ring 3. The inner cavity of the cylinder 4 is connected to the inner cavity of the filter cylinder 13 via a telescopic pipe 11. The left end of the filter cylinder 13 is connected to the inner cavity of the transformer body 1 via a one-way output pipe 12. The inner cavity of the filter cylinder 13 contains a filter structure for filtering impurities in the oil. The elastic air bladder ring 3 adopts a multi-layer composite structure, with an inner layer of oil-resistant fluororubber (2-3mm thick) and a middle layer of fluoropolymer. The fiber reinforced mesh (120 mesh) has a weather-resistant silicone coating (1mm thick) on the outside. Its coefficient of thermal expansion is matched with that of transformer oil. Under operating conditions from -40℃ to 100℃, the radial deformation of the airbag ring is ≤0.15mm. Furthermore, through the coordinated compensation of the reset airbag 9 and the elastic telescopic rod 10 (compensation rate of over 85%), the pumping error caused by thermal expansion and contraction can be eliminated. The abutment wheel 7 adopts an eccentric wheel structure (eccentricity of 8mm) and is matched with a linear bearing to convert the rotational motion into precise linear reciprocating motion (stroke error ±0.5mm). Compared with the traditional gear transmission structure, the number of parts is simplified by 67%.

[0046] The inner cavity of the circulation box 2 is equipped with a drive mechanism for driving the circulation mechanism connecting plate 5 left and right.

[0047] The drive mechanism includes a drive shaft 6 that is driven by a motor to rotate inside the circulation box 2. An abutment wheel 7 is fixedly connected to the surface of the drive shaft 6 and abuts against the side of the connecting plate 5. Both sides of the abutment wheel 7 are provided with concave surfaces 8. A reset airbag 9 is fixedly connected to the right side of the connecting plate 5 and is fixedly connected to the inner wall of the circulation box 2. The inner cavity of the reset airbag 9 is connected to the inner cavity of the elastic airbag ring 3 through a pipe. An elastic telescopic rod 10 is fixedly connected to the side wall of the transformer body 1 located inside the circulation box 2. The telescopic end of the elastic telescopic rod 10 is fixedly connected to the left side of the connecting plate 5.

[0048] Two reset airbags 9 are provided and are symmetrically arranged above and below the abutment wheel 7. By setting two reset airbags 9, when the elastic airbag ring 3 is squeezed by the connecting plate 5 and moves left and right, the pressure can be transferred to the reset airbag 9 through the oil, reducing the direct impact on the elastic airbag ring 3 and extending its service life in the long-term extension and contraction state.

[0049] The filtration structure includes a filter baffle 14 and an adsorption frame 15 fixed inside the filter cylinder 13. The right end of the filter baffle 14 is bent downward to wrap around the adsorption frame 15. There is a gap between the right end of the adsorption frame 15 and the top of the filter cylinder 13. The adsorption frame 15 is a cylindrical tube with multiple adsorption tubes on its surface. During use, under pressure fluctuations, because the oil contains heavy impurities, when the oil circulates and oscillates inside the filter cylinder 13, some of the oil containing flocculent oxides will sink below the filter baffle 14. Then, the flocculent oxides inside are blocked and adsorbed by the adsorption frame 15, and the oil is filtered upward. This allows for continuous filtration of the oil. During continuous filtration, the normal circulation of the oil is not blocked; only the oil overflowing in the circulation loop is filtered to ensure the normal circulation speed of the oil.

[0050] The bottom of the filter cartridge 13 is threadedly connected to a threaded cylinder 18. The bottom of the threaded cylinder 18 extends through and to the outside of the circulation tank 2. With the threaded cylinder 18, when a certain amount of oxides are collected inside, the valves of the telescopic pipe 11 and the one-way output pipe 12 are closed. Under the action of gravity, the large amount of impurities accumulated in the filter cartridge 13 can be discharged by opening the threaded cylinder 18. There is no need to replace all the oil. Only the oil containing impurities needs to be discharged periodically, which greatly reduces the circulation cost. Only a small amount of oil needs to be added.

[0051] The bottom of the filter cartridge 13 is provided with a first recessed section 16 and a second recessed section 17. The connection between the first recessed section 16 and the second recessed section 17 is located directly below the right end bend of the filter baffle 14. By setting the first recessed section 16 and the second recessed section 17, the oil containing oxides can enter the filter cartridge 13 more smoothly and prevent it from flowing out.

[0052] One end of the drive shaft 6 passes through and extends to the outside of the circulation box 2. A baffle 21 is fixedly connected to the surface of the drive shaft 6 on the outside of the circulation box 2. When the drive shaft 6 rotates, it drives the baffle 21 to rotate and blow air onto the heat dissipation fins 22 to assist the internal transformer oil in heat dissipation.

[0053] A water collection tank 19 with an opening at the top is fixedly connected to the surface of the transformer body 1. A drainage pipe 20 is connected to the bottom of the water collection tank 19. The drainage pipe 20 is positioned between the baffle plate 21 and the heat dissipation fins 22. When the internal oil temperature of the transformer body 1 becomes too high, the drive motor starts, driving the drive shaft 6 to rotate and causing the abutment wheel 7 to rotate. As the abutment wheel 7 rotates, it continuously abuts against the connecting plate 5. Through the concave surface 8, the connecting plate 5 can cause the cylinder 4 to continuously squeeze the elastic airbag ring 3 to the left. During this process, the oil inside the transformer body 1 is continuously circulated. Due to the unidirectional output pipe 12, a flow pattern is formed: transformer body 1 - elastic airbag ring 3 - cylinder 4 - extension... The circulation path from the constriction pipe 11 to the filter cartridge 13, the one-way output pipe 12, and the transformer body 1 drives the oil flow, which can effectively dissipate heat and filter the oil using the filter structure. It can also cope with the thermal expansion and contraction of the oil under high and low temperatures. While applying circulation, the power component of the drive unit will not come into contact with the oil inside the transformer body 1, which can maintain an effective sealing environment and ensure effective circulation. When the drive shaft 6 rotates, the valve of the drain pipe 20 automatically opens, and the rainwater collected in the water collection tank 19 will fall down and be blown onto the surface of the heat dissipation fins 22 by the wind force of the baffle 21, which can effectively dissipate heat. A single drive component can achieve multiple functions.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. An oil-immersed transformer with an oil circulation system, comprising a transformer body (1) and heat dissipation fins (22) fixed on the surface of the transformer body (1), characterized in that: A circulation box (2) is provided on the side of the transformer body (1); The inner cavity of the circulation box (2) is provided with a circulation mechanism for circulating the oil inside the transformer body (1); The circulation mechanism includes a connecting plate (5) that slides in the inner cavity of the circulation box (2) and a filter cylinder (13) that is fixed in the inner cavity of the circulation box (2). A cylinder (4) is fixedly connected to one side of the connecting plate (5). The left end of the cylinder (4) is connected to the inner cavity of the transformer body (1) through an elastic air bladder ring (3). The inner cavity of the cylinder (4) is connected to the inner cavity of the filter cylinder (13) through a telescopic pipe (11). The left end of the filter cylinder (13) is connected to the inner cavity of the transformer body (1) through a one-way output pipe (12). The inner cavity of the filter cylinder (13) is equipped with a filter structure for filtering impurities in the oil. The inner cavity of the circulation box (2) is provided with a drive mechanism for driving the circulation mechanism connecting plate (5) left and right. The driving mechanism includes a drive shaft (6) that is driven to rotate in the inner cavity of the circulation box (2) by a motor. The surface of the drive shaft (6) is fixedly connected to an abutment wheel (7) that abuts against the side of the connecting plate (5). Both sides of the abutment wheel (7) are provided with concave surfaces (8). The right side of the connecting plate (5) is fixedly connected to a reset airbag (9) that is fixedly connected to the inner wall of the circulation box (2). The inner cavity of the reset airbag (9) is connected to the inner cavity of the elastic airbag ring (3) through a pipe. The transformer body (1) is fixedly connected to the side wall of the inner cavity of the circulation box (2) with an elastic telescopic rod (10). The telescopic end of the elastic telescopic rod (10) is fixedly connected to the left side of the connecting plate (5).

2. The oil-immersed transformer with an oil circulation system according to claim 1, characterized in that: Two reset airbags (9) are provided and are symmetrically arranged above and below the abutment wheel (7).

3. An oil-immersed transformer with an oil circulation system according to claim 1, characterized in that: The filter structure includes a filter baffle (14) and an adsorption frame (15) fixed in the inner cavity of the filter cylinder (13). The right end of the filter baffle (14) is bent downward to wrap the adsorption frame (15). There is a gap between the right end of the adsorption frame (15) and the top of the filter cylinder (13). The adsorption frame (15) is a cylindrical tube with multiple adsorption tubes on its surface.

4. An oil-immersed transformer with an oil circulation system according to claim 1, characterized in that: The bottom of the filter cartridge (13) is threadedly connected to a threaded cylinder (18), the bottom of which extends through and to the outside of the circulation box (2).

5. An oil-immersed transformer with an oil circulation system according to claim 1, characterized in that: The bottom of the filter cylinder (13) is provided with a first recessed section (16) and a second recessed section (17), and the connection between the first recessed section (16) and the second recessed section (17) is located directly below the right end bend of the filter baffle (14).

6. An oil-immersed transformer with an oil circulation system according to claim 1, characterized in that: One end of the drive shaft (6) extends through and to the outside of the circulation box (2), and a spoiler (21) is fixedly connected to the surface of the drive shaft (6) on the outside of the circulation box (2).

7. An oil-immersed transformer with an oil circulation system according to claim 6, characterized in that: The surface of the transformer body (1) is fixedly connected to a water collection tank (19) with an opening at the top. The bottom of the water collection tank (19) is connected to a drainage pipe (20), which is located between the baffle plate (21) and the heat dissipation fins (22).

8. An oil-immersed transformer with an oil circulation system according to claim 1, characterized in that: The elastic airbag ring (3) adopts a multi-layer composite structure, with an inner layer of oil-resistant fluororubber, a middle layer of aramid fiber reinforced mesh, and an outer layer of weather-resistant silicone coating.

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