An oil circulating system and an oil-immersed transformer

Abstract

The present application relates to oil-immersed transformer technical field, especially relates to an oil circulating system and oil-immersed transformer, including multiple groups of heat dissipation shell, still include: circulation portion, it is arranged in the outside of heat dissipation shell, including upper oil discharge pipe and lower oil discharge pipe, when the temperature of insulating oil rises, the internal insulating oil circulation flow rate of upper oil discharge pipe and lower oil discharge pipe speeds up;Pump body, it is arranged in the outside of lower oil discharge pipe, for pumping out the insulating oil in the inside of heat dissipation shell and adjusting the flow rate of insulating oil;Blowdown portion, it is arranged in the inside of heat dissipation shell, including filter dirt plate and follow-up plate, the inside of filter dirt plate and follow-up plate is all opened filter oil hole;The present application makes the inside of shell always be filled with insulating oil, can collect and discharge oil liquid precipitation gas, avoids partial discharge;When the shell shakes, switch pump body state buffer oil impact;Buffer net reduces oil flow speed, protects coil group;Filter dirt plate filters and collects sludge when normal use;When shaking, filter dirt plate dampens and buffers the shaking of insulating oil.

Description

Technical Field

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

[0002] Oil-immersed transformers, as core equipment in power transmission and distribution systems, are widely used in various power supply scenarios such as substations and industrial and mining areas. They mainly rely on insulating oil to complete the heat dissipation and electrical insulation of the coil group. The insulating oil circulates inside the equipment, transferring the heat generated during operation to the outside, ensuring that the operating temperature of each component of the transformer is within a reasonable range.

[0003] Chinese patent CN106847473B discloses an oil-immersed transformer, including an oil tank filled with high-temperature resistant insulating oil, a transformer core installed inside the oil tank, the transformer core being immersed in the high-temperature resistant insulating oil, and a tank cover on top of the oil tank, the tank cover being sealed to the oil tank.

[0004] Chinese patent CN114628113B discloses an oil-immersed transformer, including a housing, a transformer body, a cooling assembly, an exhaust assembly, and a control assembly; the transformer body is immersed in a cavity filled with insulating oil and fixed to the housing.

[0005] When the aforementioned oil-immersed transformer is used at sea and subjected to external forces and shaking, the insulating oil flows and directly impacts the inner wall of the casing, which can easily cause structural damage. Furthermore, the internal insulating oil flows and scours the coil assembly for a long time, which in turn aggravates the coil assembly loss. Moreover, the sludge impurities produced by the oxidation of the insulating oil during long-term high-temperature operation continue to circulate with the insulating oil, and the sludge gradually deteriorates and interferes with the normal operation of the coil assembly.

[0006] Therefore, an oil circulation system and an oil-immersed transformer are needed to solve the above problems. Summary of the Invention

[0007] The purpose of this invention is to provide an oil circulation system and an oil-immersed transformer to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: an oil circulation system, comprising multiple sets of heat dissipation shells, and further comprising: The circulation section, located on the outside of the heat dissipation shell, includes an upper oil drain pipe and a lower oil drain pipe. When the temperature of the insulating oil rises, the circulation speed of the insulating oil inside the upper and lower oil drain pipes increases. The pump body, located on the outside of the lower oil drain pipe, is used to pump out the insulating oil inside the heat sink and regulate the flow rate of the insulating oil. The sewage discharge section is located inside the heat dissipation shell and includes a filter plate and a follower plate. Both the filter plate and the follower plate have oil filter holes. When the temperature of the insulating oil rises, the filter plate on the left side drives the follower plate to rotate to the right, and the overlapping area of ​​the oil filter holes inside the filter plate and the follower plate increases.

[0009] Preferably, the sewage discharge section further includes a drive shaft disposed inside the lower end of the filter plate, which drives the filter plate to rotate about the axis of the drive shaft. The lower end of the follower plate is equipped with a torsion spring rod. Under the torsion of the torsion spring rod, the follower plate always adheres tightly to the outer surface of the filter plate. The torsion spring rod is at the same height as the drive shaft. The outer surfaces of the drive shaft and the torsion spring rod are rotatably connected to the inner bottom of the heat sink. When the drive shaft drives the filter plate on the left and the follower plate to rotate to the right, the follower plate moves upward relative to the filter plate.

[0010] Preferably, the sewage discharge section further includes: The dirt-blocking strips are arranged in multiple sets on the outer surface of the dirt-blocking plate. The dirt-blocking strips are arc-shaped and their length is less than the width of the dirt-blocking plate. When the dirt-blocking plate filters the insulating oil, the sludge accumulates above the dirt-blocking strips and flows along the arc surface of the dirt-blocking strips to both sides of the dirt-blocking plate. The drain chamber is located at the bottom of the heat dissipation shell. The sludge on both sides of the filter plate slides down the upper surface of the filter plate under the action of gravity and is eventually collected by the drain chamber.

[0011] Preferably, an isolation layer is provided between the upper end of the filter plate and the inner wall of the heat sink shell. The isolation layer and the filter plate divide the internal space of the heat sink shell into an upper liquid storage chamber and a lower liquid storage chamber. The insulating oil inside the upper liquid storage chamber enters the lower liquid storage chamber through the oil filter holes in the filter plate.

[0012] Preferably, an air layer is provided on the upper part of the heat dissipation shell to collect and store gas in the insulating oil, and a pressure relief pipe is provided on the upper side of the heat dissipation shell to balance the air layer with the external atmospheric pressure.

[0013] An oil-immersed transformer, wherein the oil-immersed transformer utilizes an oil circulation system as described above for insulating oil circulation, includes a housing, and a coil assembly is disposed inside the housing, and further includes: The pressure relief pipe is located on the upper side of the housing, and the bottom of the pressure relief pipe is at the same height as the inner top of the housing. It is used to collect the gas generated by the thermal decomposition of the insulating oil inside the housing. An upper oil guide pipe connected to the upper oil drain pipe is provided on its outer side. The lower oil guide pipe is located on the outside of the machine housing and is connected to the side of the pump body away from the lower oil discharge pipe; The housing is equipped with multiple sets of sealing frames inside, and the ends of the sealing frames are equipped with buffer meshes to buffer the flow of insulating oil.

[0014] Preferably, the liquid level of the insulating oil inside the heat dissipation shell is higher than the height of the top of the casing, the coil assembly is always located inside the insulating oil, and a liquid level sensor is provided at the top of the casing to monitor the level of the insulating oil inside the casing in real time.

[0015] Preferably, the insulating oil in the heat dissipation shell and the housing circulates along the upper oil drain pipe, the lower oil drain pipe, the upper oil guide pipe, and the lower oil guide pipe.

[0016] Preferably, the height of the buffer mesh is the same as the height of the lower oil guide pipe, and the buffer mesh has multiple flow-slowing holes inside to receive the insulating oil entering the housing along the lower oil guide pipe.

[0017] The technical effects and advantages of this invention are as follows: 1. The present invention uses a pump body to ensure that the inside of the casing is always filled with insulating oil, while the air layer at the top of the heat dissipation shell collects and discharges the gas released from the insulating oil at high temperature, preventing the gas from accumulating inside the casing, causing a decrease in insulation strength and triggering partial discharge.

[0018] 2. When the housing shakes, the present invention switches the working state of the pumps on both sides to buffer the shaking of the insulating oil and prevent the insulating oil from impacting the inner wall of the housing.

[0019] 3. The present invention uses a buffer mesh inside the housing to allow the insulating oil to spread smoothly to the working area of ​​the coil assembly, preventing the insulating oil from continuously washing and rubbing against the coil assembly, thus aggravating the loss and ensuring that the structure and insulation performance of the coil assembly remain intact during long-term operation.

[0020] 4. This invention continuously filters and collects sludge impurities generated by insulating oil through the filter holes on the filter plate and the follower plate, preventing sludge from being unable to settle due to continuous circulation with the insulating oil. Furthermore, when the heat sink shakes, it balances the pressure of the lower liquid storage chamber, preventing the insulating oil from impacting the inner wall and damaging the components due to pressure fluctuations. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the present invention; Figure 3 This is a schematic diagram of the housing structure of the present invention; Figure 4 This is a schematic diagram of the internal structure of the casing of the present invention; Figure 5 This is a schematic diagram of the lower half of the heat sink shell of the present invention; Figure 6 This is a schematic diagram of the upper part of the heat dissipation shell of the present invention; Figure 7 This is a schematic diagram of the lower half of the internal structure of the heat sink housing of the present invention; Figure 8This is a schematic diagram of the exploded structure of the sewage discharge section of the present invention.

[0022] In the diagram: 1. Housing; 2. Coil assembly; 3. Pressure relief pipe; 4. Upper oil guide pipe; 5. Lower oil guide pipe; 6. Heat dissipation shell; 7. Circulation section; 701. Upper oil drain pipe; 702. Lower oil drain pipe; 8. Sewage discharge section; 801. Sewage filter plate; 802. Follower plate; 803. Oil filter hole; 804. Sewage baffle; 805. Drive shaft; 806. Sewage discharge chamber; 807. Torsion spring rod; 9. Buffer screen; 10. Pump body; 11. Pressure relief pipe; 12. Isolation layer; 13. Upper liquid storage chamber; 14. Lower liquid storage chamber; 15. Sealing frame. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] Example 1

[0025] The insulating oil inside existing oil-immersed transformers cannot circulate for heat dissipation and cannot be dynamically adjusted according to the load temperature rise. Furthermore, the oil-immersed transformer has an air layer inside. If the equipment is used at sea and is shaken by external forces, the insulating oil inside the casing 1 will vibrate and easily draw in air, causing an air gap around the coil group 2 and bringing the risk of short circuit faults. When the casing 1 shakes, the insulating oil will continuously impact the inner wall of the casing 1, causing structural damage. At the same time, the insulating oil discharged by the pump body 10 directly impacts the working area of ​​the coil group 2, and long-term scouring and friction will aggravate the wear of the coil group 2.

[0026] This invention provides Figures 1 to 8 The oil circulation system shown includes multiple sets of heat dissipation shells 6. The heat dissipation shells 6 store a large amount of insulating oil inside, and multiple sets of heat dissipation mechanisms are provided on the outer surface of the heat dissipation shells 6 to cool down the insulating oil inside the heat dissipation shells 6. The heat dissipation efficiency is improved by cooperating with the flow of insulating oil inside the housing 1 and the heat dissipation shells 6. A control unit is provided on one side of the heat dissipation shells 6.

[0027] It also includes a circulation section 7, which is located on the outside of the heat dissipation shell 6, including an upper oil drain pipe 701 and a lower oil drain pipe 702. When the temperature of the insulating oil rises, the circulation speed of the insulating oil inside the upper oil drain pipe 701 and the lower oil drain pipe 702 increases, thereby realizing the circulation flow and cooling of the insulating oil inside the heat dissipation shell 6 and the housing 1.

[0028] Pump body 10 is located outside the lower oil drain pipe 702, and one end is connected to the lower oil drain pipe 702. It is used to pump out the insulating oil inside the heat dissipation shell 6 and regulate the flow rate of the insulating oil. During normal operation, the insulating oil in the housing 1 and the heat dissipation shell 6 forms a continuous reciprocating circulation along the path of the lower oil guide pipe 5, the inner cavity of the housing 1, the pressure relief pipe 3, the upper oil guide pipe 4, the upper oil drain pipe 701, the inner cavity of the heat dissipation shell 6, and the lower oil drain pipe 702, thereby improving the heat dissipation efficiency of the insulating oil inside the housing 1.

[0029] An air layer is provided on the upper part of the heat sink 6 to collect and store the gas in the insulating oil. A pressure relief pipe 11 is provided on the upper side of the heat sink 6 to balance the air layer and the external atmospheric pressure. The gas generated by the insulating oil inside the housing 1 at high temperature enters the upper part of the heat sink 6 and eventually flows out along the pressure relief pipe 11 to avoid affecting the hydraulic stability inside the housing 1.

[0030] An oil-immersed transformer utilizes the aforementioned oil circulation system for insulating oil circulation. It includes a housing 1, and a coil group 2 is disposed inside the housing 1. The coil group 2 is a conventional iron core and coil structure.

[0031] It also includes: a pressure relief pipe 3, which is located on the upper side of the housing 1, and the bottom of the pressure relief pipe 3 is at the same height as the inner top of the housing 1. It is used to collect the gas from the thermal decomposition of the insulating oil inside the housing 1. An upper oil guide pipe 4 connected to the upper oil drain pipe 701 is provided on its outer side. The gas from the thermal decomposition of the insulating oil inside the housing 1 enters the heat dissipation shell 6 along the pressure relief pipe 3, the upper oil guide pipe 4 and the upper oil drain pipe 701, and is finally discharged along the pressure relief pipe 11 above.

[0032] The lower oil guide pipe 5 is located on the outside of the housing 1 and is connected to the pump body 10 away from the lower oil drain pipe 702. The insulating oil in the heat dissipation shell 6 and the housing 1 circulates along the upper oil drain pipe 701, the lower oil drain pipe 702, the upper oil guide pipe 4 and the lower oil guide pipe 5, further realizing the cooling effect of the insulating oil flow.

[0033] The liquid level of the insulating oil inside the heat sink 6 is higher than the height of the top of the housing 1, so that the housing 1 is always filled with insulating oil. During the vibration of the insulating oil inside the housing 1, air will not be drawn in. The coil group 2 is always inside the insulating oil, and there is no air gap. This fundamentally avoids the coil group 2 from having air bubbles drawn in due to the shaking of the insulating oil, which would cause a decrease in insulation performance.

[0034] A liquid level sensor is installed on the inner top of the housing 1 to monitor the level of insulating oil inside the housing 1 in real time. When the liquid level sensor detects that the liquid level of the insulating oil inside the housing 1 is continuously decreasing, the system determines that the housing 1 has entered an overload operation state. The insulating oil inside the housing 1 is heated and decomposes to form gas and the liquid level drops. When multiple liquid level sensors detect that the liquid level of the insulating oil inside the housing 1 fluctuates back and forth, the system determines that the heat sink 6 and the housing 1 are shaking as a whole. The liquid level of the insulating oil inside the housing 1 is affected by the shaking and fluctuates continuously.

[0035] The housing 1 is equipped with multiple sets of sealing frames 15. The ends of the sealing frames 15 are equipped with buffer nets 9 to buffer the flow of insulating oil. The height of the buffer nets 9 is the same as the height of the lower oil guide pipe 5. The buffer nets 9 are provided with multiple slow flow holes to carry the insulating oil that enters the housing 1 along the lower oil guide pipe 5, so as to avoid the insulating oil directly impacting the coil group 2 and causing structural damage.

[0036] Furthermore, the pumping operation of the pump body 10 can also drive the insulating oil to move back and forth at the buffer mesh 9, thereby clearing the slow flow holes inside the buffer mesh 9 in both directions, preventing them from becoming clogged after long-term use and affecting the flow effect of the subsequent insulating oil.

[0037] The low-temperature insulating oil discharged from the pump body 10 into the inner cavity of the housing 1 through the lower oil guide pipe 5 will directly impact the surface of the buffer mesh 9. When the insulating oil passes through multiple slow-flow holes, it is effectively dispersed and then gradually diffuses to the core working area where the coil group 2 is located at a slow flow rate, preventing the insulating oil from washing away the surface of the coil group 2.

[0038] In the initial assembly state of the equipment, the upper oil guide pipe 4 on the outside of the housing 1 and the upper drain oil pipe 701 on the outside of the heat sink 6, the lower oil guide pipe 5 and one end of the pump body 10, and the other end of the pump body 10 and the lower drain oil pipe 702 on the outside of the heat sink 6 are all connected by flange seals, thereby forming a closed insulating oil circulation path between the housing 1 and the heat sinks 6 on both sides.

[0039] During normal operation, the control unit switches the pumps 10 on both sides of the housing 1 to the discharge mode. Driven by the pumps 10, the insulating oil in the housing 1 and the heat sink 6 forms a continuous reciprocating circulation along the path of the lower oil guide pipe 5, the inner cavity of the housing 1, the pressure relief pipe 3, the upper oil guide pipe 4, the upper discharge pipe 701, the inner cavity of the heat sink 6, and the lower discharge pipe 702. Through the heat exchange between the heat sink 6 and the external environment, the heat of the insulating oil is quickly removed, effectively improving the heat dissipation efficiency of the insulating oil inside the housing 1 and ensuring the stable working temperature of core components such as the coil group 2.

[0040] During the circulation of insulating oil, the low-temperature insulating oil discharged from the pump body 10 into the inner cavity of the housing 1 through the lower oil guide pipe 5 will directly impact the surface of the buffer mesh 9. When the insulating oil passes through the slow flow hole, it is effectively dispersed and then gradually diffuses to the core working area where the coil group 2 is located at a slow flow rate.

[0041] At the same time, the buffer mesh 9 overcomes the elasticity of the sealing frame 15 and moves away from the pump body 10, further buffering the flow rate of the insulating oil. This slow-flow design can prevent the insulating oil around the coil group 2 from flowing in a concentrated manner, reduce the continuous scouring and friction loss of the insulating oil on the surface of the coil group 2, effectively extend the service life of the coil group 2, and reduce the probability of safety hazards such as the insulating oil becoming charged and partial discharge.

[0042] When the liquid level sensor synchronously detects that the liquid level of the insulating oil inside the housing 1 continues to decrease, the system determines that the housing 1 has entered an overload operation state. Under long-term high temperature environment, the insulating oil will gradually release dissolved gas, forming tiny bubbles inside the insulating oil. These bubbles migrate upward along with the insulating oil flowing inside the housing 1, continuously flowing into the pressure relief pipe 3, and finally being transported to the interior of the heat dissipation housing 6 through the upper oil guide pipe 4 and the upper oil drain pipe 701. The bubbles entering the heat dissipation housing 6 continue to rise under the action of buoyancy, and after leaving the insulating oil, they gather in the air layer reserved above the interior of the heat dissipation housing 6.

[0043] When the air pressure inside the air layer reaches the threshold, the pressure relief pipe 11 automatically opens to release the gas to the outside atmosphere. This degassing process can effectively prevent gas from accumulating inside the casing 1, prevent problems such as reduced insulation strength and partial discharge caused by air bubbles, ensure the stable operation of the transformer, and avoid the risk of safety accidents such as insulation breakdown.

[0044] At the same time, the control unit synchronously increases the operating power of the pump bodies 10 on both sides and improves the efficiency of insulating oil delivery, accelerates the circulation speed of insulating oil inside the housing 1 and heat dissipation shell 6, and further enhances the heat dissipation effect by increasing the number of heat exchange cycles per unit time, suppressing the continuous rise of oil temperature and ensuring the safe operation of the transformer under overload conditions.

[0045] When the equipment is used at sea, and the level sensors detect repeated fluctuations in the level of insulating oil inside the housing 1, the system determines that the heat sink 6 and the housing 1 are shaking as a whole. The level of the insulating oil inside the housing 1 is affected by the shaking and fluctuates continuously. Since the initial design of the system ensures that the inside of the housing 1 is always completely filled with insulating oil through the pump body 10, there is no air layer space in the inner cavity of the housing 1. Therefore, even if the housing 1 shakes with the external working conditions, the internal insulating oil will not be entrained by air during the vibration. The coil group 2 is always completely wrapped by insulating oil without any air gaps. This fundamentally avoids the safety accident of the coil group 2 being damaged by air bubbles due to the shaking of the insulating oil, which would lead to a decrease in insulation performance and cause a short circuit.

[0046] When a leftward sway is detected in the housing 1, the insulating oil inside the housing 1 will move to the right relative to the housing 1 due to its own inertia and concentrate its impact on the inner right side wall of the housing 1. At this time, the control unit immediately adjusts the working mode of the pump bodies 10 on both sides: Switch the right-side pump body 10 to suction mode and actively and quickly remove the insulating oil that is gathered on the right side of the housing 1 and is about to hit the inner wall, thereby reducing the impact of the insulating oil on the right inner wall of the housing 1. At the same time, avoid the newly discharged insulating oil from colliding head-on with the insulating oil surging to the right inside the housing 1 when the right-side pump body 10 is always in discharge mode, thus preventing the internal shaking from being aggravated.

[0047] The pump body 10 on the left side is kept in discharge mode by synchronous control. Insulating oil is continuously added to the left side of the housing 1 and the amount of oil withdrawn from the right side is replenished. This keeps the total amount of insulating oil inside the housing 1 constant and ensures that the inner cavity of the housing 1 is always full of insulating oil, thus avoiding safety accidents caused by insulation failure in all aspects.

[0048] Example 2

[0049] Based on the above embodiments, although the problems of the inability to adjust the heat dissipation efficiency of the insulating oil inside the housing 1, the easy entrapment of air during shaking, and the impact of insulating oil on the inner wall of the housing 1 and the scouring of the coil group 2 by the insulating oil have been solved, some unresolved problems still exist: First, when the equipment shakes, the internal insulating oil continuously impacts the buffer mesh 9, further aggravating the shaking amplitude of the insulating oil in the core area where the coil group 2 is located, interfering with the insulation performance and cooling stability around the coil group 2; Second, when the insulating oil flows back and forth inside the housing 1 and the heat dissipation shell 6, it will cause oil sludge impurities to flow synchronously and cannot be deposited, thereby reducing the insulation performance of the transformer.

[0050] To solve the above problems, an oil circulation system further includes a drain section 8, which is located inside the heat sink 6 and includes a filter plate 801 and a follower plate 802. Both the filter plate 801 and the follower plate 802 have oil filter holes 803. When the temperature of the insulating oil rises, the filter plate 801 in the left heat sink 6 drives the follower plate 802 to rotate to the right. The overlapping area of ​​the oil filter holes 803 inside the filter plate 801 and the follower plate 802 increases, thereby accelerating the flow rate of the insulating oil. This dynamic increase in the overlapping area can accurately match the oil discharge power of the pump body 10 after it is increased, and avoid the oil filtration speed lagging behind the oil discharge speed of the pump body 10 due to insufficient flow capacity of the oil filter holes 803.

[0051] The sewage discharge section 8 also includes a drive shaft 805 disposed inside the lower end of the filter plate 801, which is used to drive the filter plate 801 to rotate around the axis of the drive shaft 805.

[0052] A torsion spring rod 807 is provided inside the lower end of the follower plate 802. Under the torsion of the torsion spring rod 807, the follower plate 802 is always in close contact with the outer surface of the filter plate 801. The torsion spring rod 807 is at the same height as the drive shaft 805. The outer surfaces of the drive shaft 805 and the torsion spring rod 807 are rotatably connected to the inner bottom of the heat sink 6. When the drive shaft 805 drives the filter plate 801 and the follower plate 802 on the left to rotate to the right, the follower plate 802 moves upward relative to the filter plate 801, thereby adjusting the overlapping area of ​​the oil filter holes 803 on the filter plate 801 and the follower plate 802, and correspondingly adjusting the flow rate of the insulating oil.

[0053] The sewage discharge section 8 also includes: a baffle strip 804, which is arranged in multiple sets on the outer surface of the filter plate 801. The baffle strip 804 is arc-shaped and its length is less than the width of the filter plate 801. When the filter plate 801 filters the insulating oil, the sludge accumulates above the baffle strip 804 and flows along the arc surface of the baffle strip 804 to both sides of the filter plate 801.

[0054] The insulating oil in the upper liquid storage chamber 13 flows through the oil filter hole 803 and into the lower liquid storage chamber 14 under the action of gravity. The oil sludge and impurities in the insulating oil are intercepted by the filter plate 801. Under the action of its own gravity, the oil sludge slides down along the upper surface of the filter plate 801 and, under the guiding action of the baffle strip 804, gathers on both sides of the filter plate 801 to prevent the oil sludge from moving directly downward and blocking the lower oil filter hole 803.

[0055] The drain chamber 806 is located at the bottom of the heat sink 6. Under the action of gravity, the oil sludge on both sides of the filter plate 801 slides down the upper surface of the filter plate 801 and is eventually collected by the drain chamber 806. After the equipment has been running for a set period, the staff can periodically open the drain port of the drain chamber 806 to discharge the accumulated oil sludge and impurities from the system, thereby maintaining the cleanliness of the insulating oil.

[0056] An isolation layer 12 is provided between the upper end of the filter plate 801 and the inner wall of the heat sink 6. The isolation layer 12 is elastic. The isolation layer 12 and the filter plate 801 divide the internal space of the heat sink 6 into an upper liquid storage chamber 13 and a lower liquid storage chamber 14. During the rotation of the filter plate 801, the elastic deformation of the isolation layer 12 always maintains the seal. The insulating oil inside the upper liquid storage chamber 13 enters the lower liquid storage chamber 14 through the oil filter hole 803 in the filter plate 801.

[0057] In summary, during normal operation of the equipment, as the insulating oil is used for a long time, it gradually oxidizes and deteriorates under long-term high temperature conditions, and continuously generates sludge-like solid deposits. During the closed-loop circulation of the insulating oil between the heat dissipation shell 6 and the housing 1, the high-temperature insulating oil carrying sludge impurities in the housing 1 is transported to the interior of the heat dissipation shell 6 along the upper oil guide pipe 4 and the upper oil drain pipe 701, and finally enters the upper liquid storage chamber 13 formed by the isolation layer 12 and the filter plate 801.

[0058] Under the influence of gravity, the insulating oil in the upper liquid storage chamber 13 flows from top to bottom through the oil filter hole 803 and into the lower liquid storage chamber 14. During this process, the sludge and impurities in the insulating oil are intercepted by the filter plate 801, and the insulating oil smoothly enters the lower liquid storage chamber 14 through the oil filter hole 803 opened on the filter plate 801.

[0059] The sludge remaining on the upper surface of the filter plate 801 slides down the filter plate 801 under its own gravity. At the same time, it is guided by the multiple sets of arc-shaped baffles 804 on the surface of the filter plate 801 to gradually gather towards the two sides of the filter plate 801, preventing the sludge from moving directly downwards and clogging the oil filter holes 803 below.

[0060] The sludge that has accumulated to the edge continues to slide down along the side edge of the filter plate 801 and finally falls into the drain chamber 806 at the bottom of the heat sink 6 for centralized collection. After the equipment has been running for a set period, the staff can periodically open the drain port of the drain chamber 806 to discharge the accumulated sludge and impurities from the system and maintain the cleanliness of the insulating oil.

[0061] Meanwhile, as the filter plate 801 continuously filters the sludge, the drive shaft 805 drives the filter plate 801 to rotate periodically at a certain angle. The rotation of the filter plate 801 disturbs the surrounding insulating oil flow field, which on the one hand accelerates the sliding rate of the sludge to the sides and bottom of the filter plate 801, improving the sludge collection efficiency per unit time, and on the other hand, prevents the sludge from continuously accumulating at the filter holes 803 and causing blockage of the channels, thus ensuring the long-term stability of the flow capacity of the filtration passage.

[0062] During this process, the follower plate 802 is always tightly attached to the outer surface of the filter plate 801 under the pre-tightening torque of the torsion spring rod 807. It swings back and forth synchronously with the filter plate 801. In conjunction with the isolation layer 12 set at the upper end of the filter plate 801, it generates adaptive elastic deformation as the filter plate 801 rotates. This continuously seals the gap between the filter plate 801 and the inner wall of the heat sink shell 6, ensuring that the insulating oil in the upper liquid storage chamber 13 and the lower liquid storage chamber 14 can only be connected through the oil filter hole 803 on the filter plate 801 and the follower plate 802, preventing unfiltered muddy insulating oil from directly entering the lower liquid storage chamber 14.

[0063] When all level sensors detect a continuous drop in the level of insulating oil inside housing 1, the system determines that housing 1 has entered an overload operating state. At this time, the control unit synchronously increases the operating power of the pumps 10 on both sides to accelerate the circulation speed of the insulating oil, thereby enhancing heat dissipation efficiency and suppressing the continuous rise in oil temperature.

[0064] Taking the left heat sink 6 as an example, under overload conditions, the drive shaft 805 drives the filter plate 801 to rotate to the right. The filter plate 801 drives the follower plate 802 to rotate to the right together, overcoming the pre-tightening torque of the torsion spring rod 807. During the synchronous rightward swing of the filter plate 801 and the follower plate 802, the space of the lower liquid storage chamber 14 is correspondingly reduced. At the same time, the overlapping area of ​​the oil filter holes 803 arranged on the filter plate 801 and the follower plate 802 gradually increases, accelerating the filtration rate and downward flow of the insulating oil.

[0065] The dynamic increase in the overlapping area can accurately match the oil discharge power of the pump body 10 after the increase, avoid the oil filtration speed lagging behind the oil discharge speed of the pump body 10 due to insufficient flow capacity of the oil filter hole 803, prevent the lower liquid storage chamber 14 from forming a negative pressure environment due to untimely replenishment of insulating oil, avoid the vicious cycle formed by the pump body 10 continuously increasing power to offset the negative pressure, ensure the stable operation of the oil circulation system, and effectively extend the overall service life of the transformer.

[0066] The operating logic of each component inside the right heat sink 6 is symmetrical and opposite to that of the left heat sink 6. The two sides work together to achieve adaptive matching of the flow of the heat dissipation path.

[0067] When all level sensors detect that the level of insulating oil inside housing 1 fluctuates back and forth, it is determined that the heat sink 6 and housing 1 are shaking and the surface of insulating oil inside them is vibrating back and forth, and the insulating oil needs to be properly buffered.

[0068] If the entire device wobbles to the left, the insulating oil inside the left heat sink 6 moves to the right relative to the heat sink 6 due to its own inertia and hits the right inner wall of the heat sink 6. At this time, the filter plate 801 inside the left heat sink 6 rotates to the left under the driving action of the drive shaft 805.

[0069] On the one hand, the filter plate 801 that rotates to the left acts as a damping component and forms a flow resistance to the insulating oil that moves to the right, consuming the impact kinetic energy of the insulating oil, effectively buffering the impact force of the insulating oil on the inner wall of the heat sink 6, and suppressing the swaying amplitude of the internal insulating oil.

[0070] On the other hand, when the filter plate 801 rotates to the left, the follower plate 802 remains in close contact with the outer surface of the filter plate 801 under the pre-tightening torque of the torsion spring rod 807. As the filter plate 801 continues to rotate to the left, the torsion spring deformation of the torsion spring rod 807 is gradually released. When the torque of the torsion spring rod 807 is completely released, the follower plate 802 reaches the rotation limit position and stops following. At this time, the filter plate 801 continues to rotate to the left under the drive of the drive shaft 805. The contact surfaces of the filter plate 801 and the follower plate 802 are relatively misaligned and separated, and the corresponding oil filter holes 803 are completely misaligned.

[0071] Therefore, the oil filter hole 803 on the filter plate 801 is directly connected to the lower liquid storage chamber 14, so that the amount of insulating oil entering the lower liquid storage chamber 14 through the oil filter hole 803 reaches the maximum, thereby offsetting the negative pressure caused by the expansion of the volume of the lower liquid storage chamber 14 due to the leftward rotation of the filter plate 801. This ensures that the insulating oil in the upper liquid storage chamber 13 can be quickly replenished to the lower liquid storage chamber 14 through the oil filter hole 803, and avoids the formation of negative pressure in the lower liquid storage chamber 14, which would interfere with the stable discharge operation of the pump body 10.

[0072] When the housing 1 is shaken to the left, the internal insulating oil moves to the right inside the housing 1 due to inertia. The left pump body 10 switches to the discharge mode and the discharge volume increases. At this time, the discharge volume of the left pump body 10 is equal to the flow volume of the insulating oil through the buffer mesh 9. The left pump body 10 actively draws the insulating oil inside the heat dissipation shell 6 through the lower oil guide pipe 5 and discharges it into the housing 1, thereby compensating for the insulating oil on the left side inside the housing 1, avoiding the reduction of the insulating oil volume and the generation of air that would hinder the normal operation of the coil group 2.

[0073] Meanwhile, the insulating oil continuously enters the left side of the buffer screen 9 under the discharge action of the pump body 10. The buffer screen 9 buffers the insulating oil passing through the buffer screen 9, effectively suppressing the oil sloshing around the coil group 2. The insulating oil on the left side of the buffer screen 9 flows steadily into the right side. The buffer screen 9 is relatively stable inside the housing 1, preventing it from moving and affecting the flow stability of the insulating oil inside the housing 1.

[0074] Similarly, under the same leftward shaking condition, the insulating oil inside the right heat sink 6 also moves to the right relative to the housing 1 due to inertia and hits the right inner wall of the heat sink 6. The filter plate 801 inside the right heat sink 6 rotates to the left synchronously under the drive of the corresponding drive shaft 805. The follower plate 802 rotates to the left synchronously against the surface of the filter plate 801 under the pre-tightening action of the corresponding torsion spring rod 807.

[0075] On the one hand, when the filter plate 801 rotates to the left, it forms a damping barrier on the insulating oil surging to the right inside the heat sink 6 on the right side and consumes the impact energy of the insulating oil, thereby buffering the impact of the insulating oil on the inner wall of the heat sink 6 and reducing the shaking amplitude of the overall structure.

[0076] On the other hand, as the filter plate 801 continues to rotate to the left, the overlapping area of ​​the filter plate 801 and the corresponding oil filter hole 803 on the follower plate 802 gradually increases. The continuous increase in the overlapping area accelerates the flow rate of the insulating oil in the lower liquid storage chamber 14 through the oil filter hole 803 into the upper liquid storage chamber 13. This increase in the overlapping area can offset the high pressure generated by the reduction in the volume of the lower liquid storage chamber 14 due to the rotation of the filter plate 801 to the left, avoid the formation of high pressure back resistance in the lower liquid storage chamber 14, ensure the stability of the pump body 10's suction condition, and maintain the normal operation of the entire oil circulation system.

[0077] When the casing 1 shakes to the left, the insulating oil inside moves to the right due to inertia, forming a transverse insulating oil fluid that directly impacts the surface of the buffer mesh 9. The right pump body 10 switches to suction mode and increases the suction volume. At this time, the suction volume of the right pump body 10 is greater than the flow of insulating oil through the buffer mesh 9, that is, the suction volume of the right pump body 10 is greater than the discharge volume of the left pump body 10. This flow difference is adaptively adjusted according to the magnitude of the shaking force. At this time, the insulating oil near the right side of the buffer mesh 9 is actively sucked through the lower oil guide pipe 5, so that the insulating oil on the right side inside the casing 1 is quickly discharged, avoiding excessive insulating oil volume and impact damage to the inner wall of the casing 1.

[0078] Meanwhile, as the insulating oil on the right side of the buffer mesh 9 gradually decreases and the resistance to the buffer mesh 9 decreases, the buffer mesh 9 moves to the right under the suction action of the pump body 10, further buffering the impact of the insulating oil on the buffer mesh 9, reducing the amount of return after the insulating oil impacts the buffer mesh 9, weakening the peak impact load of the insulating oil on the surface of the buffer mesh 9, avoiding the reflection of the insulating oil from colliding with the rest of the insulating oil and amplifying the sloshing amplitude, effectively suppressing the sloshing of the oil in the area surrounding the coil group 2. At the same time, the movement of the buffer mesh 9 to the right can also effectively reduce the impact force of the insulating oil on the inner wall of the right side of the housing 1, preventing the insulating oil inside the housing 1 from turbulent flow and affecting its normal cooling effect on the coil group 2.

[0079] Maintaining the casing 1 fully filled with oil throughout the process means that slight changes in the amount of insulating oil inside the casing 1 will not affect its normal insulation and cooling effect on the coil group 2.

[0080] Similarly, when the equipment swings to the right, the movement process is reversed.

[0081] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An oil circulation system, comprising multiple sets of heat dissipation shells (6), characterized in that, Also includes: The circulation section (7) is located on the outside of the heat dissipation shell (6) and includes an upper oil drain pipe (701) and a lower oil drain pipe (702). When the temperature of the insulating oil rises, the circulation speed of the insulating oil inside the upper oil drain pipe (701) and the lower oil drain pipe (702) increases. Pump body (10), which is located outside the lower oil drain pipe (702), is used to pump out the insulating oil inside the heat sink shell (6) and regulate the flow rate of the insulating oil; The drain section (8) is located inside the heat sink (6) and includes a filter plate (801) and a follower plate (802). Both the filter plate (801) and the follower plate (802) have oil filter holes (803). When the temperature of the insulating oil rises, the filter plate (801) on the left side drives the follower plate (802) to rotate to the right, and the overlapping area of ​​the oil filter holes (803) inside the filter plate (801) and the follower plate (802) increases.

2. The oil circulation system according to claim 1, characterized in that, The sewage discharge section (8) also includes a drive shaft (805) provided inside the lower end of the filter plate (801) for driving the filter plate (801) to rotate around the axis of the drive shaft (805); The lower end of the follower plate (802) is provided with a torsion spring rod (807). Under the torsion of the torsion spring rod (807), the follower plate (802) is always in close contact with the outer surface of the filter plate (801). The torsion spring rod (807) is at the same height as the drive shaft (805). The outer surfaces of the drive shaft (805) and the torsion spring rod (807) are rotatably connected to the inner bottom of the heat sink (6). When the drive shaft (805) drives the filter plate (801) and the follower plate (802) on the left to rotate to the right, the follower plate (802) moves upward relative to the filter plate (801).

3. The oil circulation system according to claim 2, characterized in that, The sewage discharge section (8) also includes: A baffle strip (804) is provided in multiple sets on the outer surface of the filter plate (801). The baffle strip (804) is arc-shaped and its length is less than the width of the filter plate (801). When the filter plate (801) filters the insulating oil, the sludge accumulates above the baffle strip (804) and flows along the arc surface of the baffle strip (804) to both sides of the filter plate (801). The drain chamber (806) is located at the bottom of the heat sink (6). The sludge on both sides of the filter plate (801) slides down along the upper surface of the filter plate (801) under the action of gravity and is eventually collected by the drain chamber (806).

4. The oil circulation system according to claim 1, characterized in that, An isolation layer (12) is provided between the upper end of the filter plate (801) and the inner wall of the heat sink (6). The isolation layer (12) and the filter plate (801) divide the internal space of the heat sink (6) into an upper liquid storage chamber (13) and a lower liquid storage chamber (14). The insulating oil inside the upper liquid storage chamber (13) enters the lower liquid storage chamber (14) through the oil filter hole (803) in the filter plate (801).

5. The oil circulation system according to claim 1, characterized in that, An air layer is provided on the upper part of the heat dissipation shell (6) to collect and store the gas in the insulating oil. A pressure relief pipe (11) is provided on the upper side of the heat dissipation shell (6) to balance the air layer and the external atmospheric pressure.

6. An oil-immersed transformer, wherein the oil-immersed transformer utilizes an oil circulation system as described in claim 1 for circulating insulating oil, comprising a housing (1), wherein a coil assembly (2) is disposed inside the housing (1), characterized in that, Also includes: Pressure relief pipe (3) is located on the upper side of housing (1), and the bottom of pressure relief pipe (3) is at the same height as the inner top of housing (1). It is used to collect the gas from the decomposition of insulating oil inside housing (1) by heat. An upper oil guide pipe (4) connected to the upper oil drain pipe (701) is provided on its outer side. The lower oil guide pipe (5) is located on the outside of the housing (1) and connected to the side of the pump body (10) away from the lower oil drain pipe (702); The housing (1) is provided with multiple sets of sealing frames (15) inside, and the ends of the sealing frames (15) are provided with buffer nets (9) to buffer the flow of insulating oil.

7. An oil-immersed transformer according to claim 6, characterized in that, The level of the insulating oil inside the heat sink (6) is higher than the height of the top inside the housing (1). The coil group (2) is always located inside the insulating oil. A liquid level sensor is installed at the top inside the housing (1) to monitor the level of the insulating oil inside the housing (1) in real time.

8. An oil-immersed transformer according to claim 6, characterized in that, The insulating oil in the heat sink (6) and the housing (1) circulates along the upper oil drain pipe (701), the lower oil drain pipe (702), the upper guide oil pipe (4), and the lower guide oil pipe (5).

9. An oil-immersed transformer according to claim 6, characterized in that, The height of the buffer mesh (9) is the same as the height of the lower oil guide pipe (5). Multiple slow-flow holes are provided inside the buffer mesh (9) to receive the insulating oil that enters the housing (1) along the lower oil guide pipe (5).

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