A structure of an oil-immersed transformer

Abstract

This utility model relates to the field of transformer technology, and in particular to an oil-immersed transformer structure, including an oil tank, a transformer body, an oil layer, and an air layer; several support plates are disposed on the inner wall of the tank, and the support plates are arranged along the length and width of the tank body; on the same inner wall of the tank body, several guide channels are formed between the support plates, the inner wall of the tank body, and the corresponding oil guide plates; the inside of the tank body is connected to the guide channels, and the guide channels are used to supply the oil layer to flow along the height direction of the tank body; the air layer is disposed at the upper part of the tank body, and the air layer is located above the oil layer; this utility model improves the fluidity of hot oil, increases the contact area between hot oil and the inner wall of the tank body, thereby improving the heat dissipation power of the oil tank and improving the heat dissipation effect of the oil tank, solving the problems of poor hot oil fluidity, limited contact area between hot oil and the tank wall, which prevents the surface temperature of the oil tank from being increased, resulting in poor heat dissipation effect of the oil tank and affecting the normal operation of the transformer.

Description

Technical Field

[0001] This utility model relates to the field of transformer technology, and in particular to an oil-immersed transformer structure. Background Technology

[0002] Self-cooled oil-immersed transformers primarily dissipate heat through natural convection and thermal radiation between the oil tank and the air via radiators. Generally, smaller capacity transformers generate less heat and typically do not require radiators, relying mainly on the oil tank for cooling; the oil tank's cooling power accounts for a large proportion of the total cooling power. Larger capacity transformers, on the other hand, generate more heat, and the oil tank alone cannot effectively dissipate it, requiring radiators to enhance cooling; in this case, the radiator's cooling power accounts for a large proportion of the total cooling power. Both the oil tank's cooling power and the radiator's cooling power are important components of the transformer's total cooling power. Improving the oil tank's cooling power, i.e., improving the oil tank's cooling effect, helps to improve the transformer's overall cooling capacity and performance.

[0003] According to the convective heat transfer formula Q=K*A*△T (where K is the convective heat transfer coefficient, A is the surface area of ​​the oil tank, and △T is the temperature difference between the surface of the oil tank and the air) and the thermal radiation heat transfer formula Q=ε*A*σ*(T1) 4 -T2 4 (In the formula, A is the surface area of ​​the oil tank, σ is the radiation coefficient, T1 is the surface temperature of the oil tank, and T2 is the air temperature) it can be seen that increasing the surface temperature of the oil tank can improve the heat dissipation power of the oil tank, that is, it can improve the heat dissipation effect of the oil tank.

[0004] During stable operation, the oil temperature distribution inside the tank of an oil-immersed transformer is uneven. This is because the heat generated during transformer operation heats the transformer oil inside the tank. After heating, the density of the transformer oil decreases, and it naturally flows upwards under gravity. Therefore, hot oil accumulates in the upper part of the transformer, while colder oil, with a higher density, mainly accumulates in the lower part. This results in a temperature distribution characteristic where the oil temperature is higher at the top and lower at the bottom. At this point, the surface temperature of the tank near the top is higher than that at other locations. However, existing oil-immersed transformers have poor oil flow, and the limited contact area between the hot oil and the tank wall fails to raise the surface temperature of the tank. This leads to poor heat dissipation in the tank, low heat dissipation capacity of the transformer, and affects its normal operation. Utility Model Content

[0005] The main objective of this invention is to provide an oil-immersed transformer structure that improves the fluidity of hot oil, increases the contact area between the hot oil and the inner wall of the tank, and raises the surface temperature of the tank, thereby improving the heat dissipation power of the tank. This enhances the heat dissipation effect of the tank and further improves the heat dissipation power of the transformer, ensuring normal operation of the transformer. This invention solves the problems of poor hot oil fluidity, limited contact area between the hot oil and the tank wall, which prevents the increase of the tank surface temperature, resulting in poor heat dissipation effect and low heat dissipation power of the transformer, thus affecting its normal operation.

[0006] To achieve the above objectives, the present invention proposes an oil-immersed transformer structure, which includes an oil tank, a transformer body, an oil layer, and a gas layer.

[0007] The oil tank includes a tank body, several support plates, and several oil guide plates; the several support plates are disposed on the inner wall of the tank body, and the several support plates are arranged along the length and width directions of the tank body, and each support plate extends along the height direction of the tank body; the oil guide plates are disposed opposite to the inner wall of the tank body.

[0008] On the same inner wall surface of the housing, one end of several of the support plates away from the housing is connected to the oil guide plate;

[0009] On the same inner wall surface of the housing, a plurality of the support plates form a plurality of flow channels between the inner wall surface of the housing and the corresponding oil guide plates; the interior of the housing is connected to the flow channels, and the flow channels are used to allow the oil layer to flow along the height direction of the housing;

[0010] The device body, the oil layer, and the gas layer are all disposed within the housing. The device body is located at the lower part of the housing, and the oil layer encloses the device body, the support plate, and the oil guide plate. The gas layer is disposed at the upper part of the housing and is located above the oil layer.

[0011] Optionally, the distance L1 between the oil guide plate and the inner wall of the box is 3-15mm.

[0012] Optionally, the body includes a winding, and the vertical distance L2 between the outer diameter of the winding and the oil guide plate along the radial direction of the winding is greater than the distance L1 between the oil guide plate and the inner wall of the housing.

[0013] Optionally, the thickness L3 of the oil guide plate is 3-5 mm.

[0014] Optionally, on the same inner wall surface of the housing, the distance L4 between two adjacent support plates is 20-200mm.

[0015] Optionally, several support plates located on the same inner wall of the box are evenly arranged.

[0016] Optionally, the two ends of the oil guide plate along the height direction of the housing are flush with the two ends of the support plate along the height direction of the housing.

[0017] Optionally, the distance L5 between the bottom end of the oil guide plate and the bottom end of the housing is 100-200mm.

[0018] Optionally, the distance L6 between the top of the oil guide plate and the top of the oil layer is 100-200mm.

[0019] Optionally, four oil guide plates are provided, and the four oil guide plates are connected in sequence to form a rectangle.

[0020] Compared with the prior art, the embodiments of this utility model have the following beneficial effects:

[0021] In this oil-immersed transformer structure, several support plates are installed on the inner wall of the tank, arranged along the length and width of the tank. Oil guide plates are positioned opposite the inner wall of the tank, connected by the support plates. On the same inner wall of the tank, several support plates form flow channels between themselves, the inner wall, and the corresponding oil guide plates. These channels allow the oil layer to flow along the height of the tank, guiding the transformer oil. When the outer wall of the tank experiences air convection and heat radiation, the transformer oil in the flow channels undergoes heat exchange due to direct contact with the inner wall, causing the temperature of the oil in the channels to decrease and its density to gradually decrease. The increased flow of hot oil along the guide channel towards the bottom of the tank allows the oil accumulated on the upper part of the oil layer to flow towards the bottom of the tank under pressure. This improves the fluidity of the hot oil, increases the contact area between the hot oil and the inner wall of the tank, and raises the surface temperature of the tank. This enhances the heat dissipation capacity of the tank, thereby improving the heat dissipation effect of the tank and further improving the heat dissipation capacity of the transformer, ensuring normal operation of the transformer. In addition, the air layer acts as a buffer space, preventing the tank from deforming due to the expansion of the transformer oil as the temperature rises. It also prevents the tank from bursting due to pressure rise when the transformer body is malfunctioning, thus improving the safety of this oil-immersed transformer structure. Attached Figure Description

[0022] Figure 1 This is a cross-sectional view of an oil-immersed transformer structure according to an embodiment of the present invention, taken at the oil layer location.

[0023] Figure 2 This is a schematic diagram of the structure (hidden body) of an oil-immersed transformer according to an embodiment of the present invention;

[0024] Figure 3 for Figure 1 Enlarged view of point A in the middle;

[0025] Figure 4 This is a cross-sectional view (front view) of an oil-immersed transformer structure according to an embodiment of the present invention;

[0026] Figure 5 This is a cross-sectional view (side view) of an oil-immersed transformer structure according to an embodiment of the present invention.

[0027] In the attached diagram: 1. Oil tank; 11. Tank body; 12. Support plate; 13. Oil guide plate; 14. Flow guide groove; 2. Body; 21. Winding; 3. Oil layer; 4. Gas layer. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0030] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean 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 utility model according to the specific circumstances.

[0031] Furthermore, in this utility model, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the word "and / or" throughout the text means including three parallel solutions; taking "A and / or B" as an example, it includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0032] This utility model proposes a structure for an oil-immersed transformer.

[0033] In the embodiments of this utility model, such as Figures 1 to 5 As shown, the structure of the oil-immersed transformer includes an oil tank 1, a transformer body 2, an oil layer 3, and an air layer 4;

[0034] The oil tank 1 includes a tank body 11, a plurality of support plates 12 and a plurality of oil guide plates 13; the plurality of support plates 12 are disposed on the inner wall of the tank body 11, and the plurality of support plates 12 are arranged along the length and width of the tank body 11, and each support plate 12 extends along the height of the tank body 11; the oil guide plates 13 are disposed opposite to the inner wall of the tank body 11.

[0035] On the same inner wall surface of the housing 11, several support plates 12 are connected to the oil guide plate 13 at the ends away from the housing 11.

[0036] On the same inner wall surface of the box 11, several support plates 12 form several guide channels 14 between the inner wall surface of the box 11 and the corresponding oil guide plates 13; the inside of the box 11 is connected to the guide channels 14, and the guide channels 14 are used to supply the oil layer 3 to flow along the height direction of the box 11.

[0037] The vessel body 2, oil layer 3 and gas layer 4 are all located inside the housing 11. The vessel body 2 is located at the lower part of the housing 11. The oil layer 3 encloses the vessel body 2, the support plate 12 and the oil guide plate 13. The gas layer 4 is located at the upper part of the housing 11 and is located above the oil layer 3.

[0038] In this oil-immersed transformer structure, several support plates 12 are disposed on the inner wall surface of the tank 11, and the support plates 12 are arranged along the length and width directions of the tank 11. Oil guide plates 13 are disposed opposite to the inner wall surface of the tank 11, and the support plates 12 connect the oil guide plates 13 to the inner wall surface of the tank 11. On the same inner wall surface of the tank 11, several support plates 12 form a flow channel 14 between the inner wall surface of the tank 11 and the corresponding oil guide plates 13. The oil supply layer 3 flows along the height direction of the tank 11 through the flow channel 14, guiding the transformer oil. When the outer wall of the tank 11 undergoes air convection and heat radiation heat dissipation, the transformer oil in the flow channel 14 undergoes heat exchange due to direct contact with the inner wall surface of the tank 11. As the temperature decreases, the density of the oil gradually increases and flows along the guide channel 14 towards the bottom of the tank 11. This allows the hot oil accumulated on the upper part of the oil layer 3 to enter the guide channel 14 under pressure and flow towards the bottom of the tank 11, improving the fluidity of the hot oil and increasing the contact area between the hot oil and the inner wall of the tank 11. This raises the surface temperature of the tank 11, thereby increasing the heat dissipation power of the oil tank 1. This improves the heat dissipation effect of the oil tank 1 and further enhances the heat dissipation power of the transformer, ensuring normal operation of the transformer. In addition, by setting the air layer 4, it can act as a buffer space to prevent the tank 11 from deforming due to the expansion of the transformer oil volume after the temperature rises. It can also prevent the oil tank 1 from bursting due to pressure rise when the transformer body 2 is malfunctioning, thus improving the safety of this oil-immersed transformer structure.

[0039] This invention solves the problems of poor hot oil flow, limited contact area between hot oil and tank wall, which prevents the oil tank surface temperature from being raised, resulting in poor heat dissipation of the oil tank, low heat dissipation power of the transformer, and affecting the normal operation of the transformer in existing oil-immersed transformers.

[0040] It should be noted that oil layer 3 refers to the transformer oil added inside the tank 11; air layer 4 refers to the air layer between the level of the transformer oil and the inner wall of the top of the tank 11.

[0041] To further explain, by adopting this oil-immersed transformer structure, the heat dissipation efficiency of oil tank 1 can be increased by more than 40%, and the heat dissipation power of oil tank 1 accounts for about 10%-40%, and the total heat dissipation power of the oil-immersed transformer can be increased by 4%-16%.

[0042] It is understandable that the length direction of the support plate 12 and the height direction of the oil guide plate 13 are the same as the height direction of the box 11.

[0043] like Figure 1 and 3 As shown, in one embodiment of this application, the distance L1 between the oil guide plate 13 and the inner wall of the housing 11 is 3-15mm.

[0044] In this invention, the transformer oil in the guide channel 14 is in direct contact with the inner wall of the tank 11. When the outer wall of the tank 11 undergoes air convection and heat radiation heat dissipation, the temperature of the transformer oil in the guide channel 14 decreases, its density increases, and it flows towards the bottom of the tank 11 under the action of gravity. However, the flow rate of transformer oil is usually low. If the distance between the guide plate 13 and the inner wall of the tank 11 is too large, the transformer oil is prone to generate eddies between the guide plate 13 and the inner wall of the tank 11, increasing the flow resistance of the transformer oil. At this time, the hot oil has poor fluidity, which reduces the heat dissipation effect of the tank 1. If the distance between the guide plate 13 and the inner wall of the tank 11 is too small, the hot oil has low fluidity when the transformer oil has a certain viscosity, and it is impossible to increase the contact area between the hot oil and the inner wall of the tank 11, so it is impossible to increase the surface temperature of the tank 1.

[0045] like Figure 3 As shown, in one embodiment of this application, the body 2 includes a winding 21, and the vertical distance L2 between the outer diameter of the winding 21 and the oil guide plate 13 along the radial direction of the winding 21 is greater than the distance L1 between the oil guide plate 13 and the inner wall surface of the housing 11.

[0046] Due to limitations in insulation distance, cost, and laminated wood materials (laminated wood can be used for winding 21 support and insulation, etc.), increasing the size of the oil tank 1 cannot improve its heat dissipation effect. Although increasing the size of the oil tank 1 can increase the oil storage capacity, it will lead to a significant increase in transformer oil consumption and the material cost of the tank 11. Secondly, a certain insulation distance needs to be maintained between the winding 21 and the oil guide plate 13 to meet electrical safety requirements. In this oil-immersed transformer structure, the vertical distance L2 between the outer diameter of the winding 21 and the oil guide plate 13 along the radial direction of the winding 21 is greater than the distance L1 between the oil guide plate 13 and the inner wall of the tank 11. In this way, not only can electrical safety requirements be met, but the transformer oil can also have suitable fluidity, thereby increasing the contact area between the hot oil and the inner wall of the tank 11, thus improving the heat dissipation effect of the oil tank 1 and increasing the heat dissipation power of the transformer.

[0047] like Figure 1 and 3 As shown, in one embodiment of this application, the thickness L3 of the oil guide plate 13 is 3-5 mm.

[0048] Due to limitations imposed by the dimensions of the oil tank 1, the insulation distance between the oil tank 1 and the winding 21, and the insulation distance between the winding 21 and the oil guide plate 13, the thickness L3 of the oil guide plate 13 needs to be controlled. However, because the oil guide plate 13 is relatively long, if its thickness is too small, its strength will be low, making it prone to damage under oil flow impact and vibrations caused by external forces. This invention sets the thickness L3 of the oil guide plate 13 to 3-5mm, giving it higher strength and ensuring it can withstand oil flow impact and vibrations caused by external forces, thus preventing damage and further extending the service life of this oil-immersed transformer structure.

[0049] like Figure 1 and 3 As shown, in one embodiment of this application, the distance L4 between two adjacent support plates 12 on the same inner wall surface of the housing 11 is 20-200mm.

[0050] By setting the distance L4 between two adjacent support plates 12 on the inner wall of the same housing 11 to 20-200mm, a flow channel 14 with a suitable opening size can be formed between the oil guide plate 13 and several support plates 12, ensuring that the transformer oil can smoothly pass through the flow channel 14 and flow along the flow channel 14 to the bottom of the housing 11. It can also ensure a stable connection between the oil guide plate 13 and several support plates 12, improve the structural strength of the oil guide plate 13 and support plates 12, and thus improve the quality of the oil-immersed transformer structure.

[0051] like Figures 1 to 3 As shown, in one embodiment of this application, several support plates 12 located on the inner wall of the same housing 11 are evenly arranged.

[0052] When several support plates 12 located on the inner wall of the same tank 11 are evenly arranged, a regularly arranged flow channel 14 is formed between the inner wall of the tank 11 and the corresponding oil guide plate 13. In this way, when the hot oil in the upper part of the oil layer 3 enters the flow channel 14 and flows along the flow channel 14, the hot oil entering each flow channel 14 has a relatively uniform flow rate. The hot oil has high fluidity, which can increase the contact area between the hot oil and the inner wall of the tank 11 and improve the heat dissipation effect of the oil tank 1. In addition, the structure of this oil-immersed transformer has high strength, which can further extend the service life of this oil-immersed transformer structure.

[0053] like Figure 4 and 5 As shown, in one embodiment of this application, the two ends of the oil guide plate 13 along the height direction of the housing 11 are flush with the two ends of the support plate 12 along the height direction of the housing 11.

[0054] When the two ends of the oil guide plate 13 along the height direction of the tank 11 are aligned with the two ends of the support plate 12 along the height direction of the tank 11, not only is the connection stability between the oil guide plate 13 and several support plates 12 high, allowing transformer oil to flow smoothly into each guide groove 14, but the installation difficulty of the oil guide plate 13 and support plate 12 is also reduced. This oil-immersed transformer structure has the characteristics of high stability in use.

[0055] like Figure 4 and 5 As shown, in one embodiment of this application, the distance L5 between the bottom end of the oil guide plate 13 and the bottom end of the housing 11 is 100-200mm.

[0056] By setting the distance L5 between the bottom of the oil guide plate 13 and the bottom of the housing 11 to 100-200mm, a space for transformer oil to flow can be formed between the oil guide plate 13 and the bottom of the housing 11, ensuring that the transformer oil can pass smoothly through the guide groove 14.

[0057] like Figure 4 and 5 As shown, in one embodiment of this application, the distance L6 between the top of the oil guide plate 13 and the top of the oil layer 3 is 100-200mm.

[0058] By setting the distance L6 between the oil guide plate 13 and the top of the oil layer 3 to 100-200mm, a suitable flow space can be provided for the hot oil in the upper part of the oil layer 3, so that the hot oil has high fluidity and can smoothly enter the guide groove 14.

[0059] like Figure 1 and 2 As shown, in one embodiment of this application, four oil guide plates 13 are provided, and the four oil guide plates 13 are connected in sequence to form a rectangle.

[0060] By setting four oil guide plates 13, which are connected in sequence and form a rectangle, more flow channels 14 can be formed inside the tank 11, promoting the flow of transformer oil and allowing the hot oil to fully contact the four inner walls of the tank 11. This increases the surface temperature of the four walls of the tank 11, accelerates the temperature rise of the tank 11, and ultimately improves the heat dissipation power of the tank 1, thereby improving the heat dissipation effect of the tank 1, increasing the heat dissipation power of the transformer, and ensuring the normal operation of the transformer.

[0061] It should be noted that the oil guide plate 13 is made of insulating material. Preferably, the oil guide plate 13 is made of laminated wood.

[0062] The technical principles of this utility model have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of this utility model and should not be construed as limiting the scope of protection of this utility model in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of this utility model without any inventive effort, and these embodiments will all fall within the scope of protection of this utility model.

Claims

1. An oil-immersed transformer structure, characterized by comprising: The oil tank, the body, the oil layer and the gas layer are included. The oil tank comprises a tank body, a plurality of support plates and a plurality of oil guide plates; the plurality of support plates are arranged on the inner wall surface of the tank body, and the plurality of support plates are arranged along the length direction and the width direction of the tank body, and each of the support plates extends along the height direction of the tank body; the oil guide plate is arranged opposite to the inner wall surface of the tank body. On the same inner wall surface of the tank body, the plurality of support plates are connected to the oil guide plate away from one end of the tank body. On the same inner wall surface of the tank body, the plurality of support plates form a plurality of flow guide grooves between the inner wall surface of the tank body and the corresponding oil guide plate; the tank body is in communication with the flow guide grooves, and the flow guide grooves are used for the oil layer to flow along the height direction of the tank body. The body, the oil layer and the gas layer are arranged in the tank body, the body is located in the lower part of the tank body, the oil layer wraps the body, the support plates and the oil guide plates; the gas layer is arranged in the upper part of the tank body, and the gas layer is located above the oil layer.

2. The oil-immersed transformer structure according to claim 1, characterized by The distance L1 between the oil guide plate and the inner wall surface of the tank body is 3-15 mm.

3. The oil-immersed transformer structure according to claim 1, characterized by The body comprises a winding, and the perpendicular distance L2 between the outer diameter of the winding and the oil guide plate along the radial direction of the winding is greater than the distance L1 between the oil guide plate and the inner wall surface of the tank body.

4. The oil-immersed transformer structure according to claim 3, characterized by The thickness L3 of the oil guide plate is 3-5 mm.

5. The oil-immersed transformer structure according to claim 1, characterized by On the same inner wall surface of the tank body, the spacing L4 between the adjacent two support plates is 20-200 mm.

6. The oil-immersed transformer structure according to claim 5, characterized by The plurality of support plates arranged on the same inner wall surface of the tank body are uniformly arranged.

7. The oil-immersed transformer structure according to claim 1, characterized by The two ends of the oil guide plate along the height direction of the tank body are flush with the two ends of the support plate along the height direction of the tank body.

8. The oil-immersed transformer structure according to claim 7, characterized by The distance L5 between the bottom end of the oil guide plate and the bottom end of the tank body is 100-200 mm.

9. The oil-immersed transformer structure according to claim 7, characterized by The distance L6 between the top end of the oil guide plate and the top end of the oil layer is 100-200 mm.

10. The oil-immersed transformer structure according to claim 1, characterized by The oil guide plate is provided with four oil guide plates, and the four oil guide plates are sequentially connected and enclosed into a rectangle.

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