An explosion-proof oil-immersed transformer for mine

Abstract

This invention discloses a mine-use explosion-proof oil-immersed transformer, comprising a square-shaped transformer tank. The winding coils are fixedly mounted inside the transformer tank using mounting brackets. Hollow pressure relief chambers are located on the left and right sides of the transformer tank. The lower ends of the pressure relief chambers are connected to the inside of the transformer tank via connecting pipes. When the internal pressure of the transformer tank reaches the threshold of the pressure valve connected to the connecting pipes, the oil in the transformer tank enters the pressure relief chambers through the connecting pipes. This mine-use explosion-proof oil-immersed transformer employs a novel structural design. When the pressure inside the transformer tank rises rapidly, the oil expands and flows back to the oil storage tank through the delivery pipe, achieving initial pressure relief. If the oil continues to expand, after the pressure reaches the threshold of the pressure valve, the oil inside the transformer tank enters the pressure relief chambers through the connecting pipes for further pressure relief. Ultimately, through these two pressure relief processes, the internal pressure of the transformer tank is reduced, achieving the purpose of explosion-proof protection.

Description

Technical Field

[0001] This invention relates to the field of transformer technology, specifically to a mining explosion-proof oil-immersed transformer. Background Technology

[0002] Mining transformers are power transformers specifically designed and manufactured for the mining environment. They convert high-voltage electricity on the surface into safe low-voltage electricity that can be used by various underground equipment. Oil-immersed transformers, in particular, use oil to fill the transformer tank, achieving insulation and heat dissipation through the oil.

[0003] As in the prior art, Chinese patent application number CN202122794310.3 discloses an oil-immersed mining transformer, which includes a transformer body, heat sink, base and support legs; an auxiliary support seat is provided on the side of the transformer body, and a cooling component is provided on the auxiliary support seat; the cooling component includes a shell, an inner cavity, an injection port and a small fan; a fixed support, an extension rod and a temperature sensor are provided on the upper end of the shell; an outlet port is provided with an outlet pipe and a receiving pipe, and a receiving chamber is provided on the base of the transformer body, and a receiving cavity is opened in the receiving chamber. The receiving cavity and the receiving pipe are connected through a first air supply pipe, and several outlets are opened on the upper end face of the receiving chamber.

[0004] For example, in the prior art, Chinese patent application number CN202020304827.2 discloses an explosion-proof enclosure for an oil-immersed mining transformer, including a first outer shell, a fan, a power supply, and a lighting lamp. A first drive motor is fixedly installed at the top of the inside of the first outer shell. A fan is fixed to the lower surface of the connecting block. Side plates are welded to both the left and right ends of the connecting plate. Filter screens are installed on both the left and right ends of the first outer shell. A crossbar is fixed to the lower surface of the mesh plate. A power supply is installed on the front end surface of the first gear. Lighting lamps are fixed to both the left and right ends of the first gear. A connecting rod is connected to the inner end surface of the second gear. A second drive motor is installed inside the second outer shell. A support rod is connected to the lower surface of the fixing plate.

[0005] For example, in the prior art, Chinese patent application number CN201920944196.8 discloses an oil-immersed mining transformer that facilitates oil replenishment. It includes a fixed base, an oil tank, a push plate, a spring, a hollow cylinder, a movable rod, a movable column, a lower oil pipe, and a connecting pipe. The fixed base is fixed on the left side of the upper end face of the transformer body, the oil tank is installed on the upper end face of the fixed base, the hollow cylinder is installed on the right side of the fixed base, the movable column is installed inside the hollow cylinder, the lower oil pipe is installed inside the movable column, the movable rod is fixed on the upper end face of the movable column, the push plate is installed on the upper end face of the movable rod, the spring is sleeved on the annular side of the movable rod, and a connecting pipe is installed between the oil tank and the hollow cylinder. This design solves the problem of inconvenient oil replenishment in the original oil-immersed mining transformer.

[0006] Based on the above information, it can be seen that existing oil-immersed transformers achieve insulation and heat dissipation by filling with oil. However, in actual use, a large amount of current flows through the transformer, generating a large amount of heat. Especially when a fault occurs (such as a short circuit), the heat rises sharply, the oil vaporizes and expands, the internal pressure of the transformer tank increases, and there is a risk of explosion. Summary of the Invention

[0007] The purpose of this invention is to provide a mine-use explosion-proof oil-immersed transformer to solve the problem of explosion hazard caused by temperature rise mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a mining explosion-proof oil-immersed transformer, comprising a transformer housing with a square structure, wherein the winding coils are fixedly installed inside the transformer housing using a mounting bracket, and pressure relief chambers with a cavity structure are provided on the left and right sides inside the transformer housing. The lower end of the pressure relief chamber is connected to the inside of the transformer housing through a connecting pipe. When the pressure inside the transformer housing reaches the threshold of the pressure valve connected to the connecting pipe, the oil in the transformer housing enters the pressure relief chamber through the connecting pipe for further pressure relief. Finally, the internal pressure of the transformer housing is reduced through two pressure reliefs to achieve the purpose of explosion protection. Heat exchangers are fixedly installed on the front and rear sides of the transformer housing. The upper and lower ends of the heat exchangers are respectively equipped with an oil inlet pipe and an oil outlet pipe connected to the transformer housing. The suction action generated by the delivery pump draws the oil inside the transformer housing into the heat exchanger through the oil inlet pipe, and then discharges it into the inside of the transformer housing through the lower oil outlet pipe. During this process, heat exchange with the air is used to dissipate heat from the oil. Furthermore, a connecting pipe is provided inside the transformer housing, which is connected to the oil inlet pipe through a lifting mechanism on the left and right sides inside the transformer housing to change the oil inlet position.

[0009] Preferably, an oil storage tank is fixedly installed on the upper surface of the transformer housing, and the oil storage tank is connected to the inside of the transformer housing through a delivery pipe. A temperature sensor is fixedly installed inside the transformer housing. When the temperature inside the transformer housing rises sharply, the oil expands and flows back to the oil storage tank through the delivery pipe, thereby achieving the purpose of initial pressure relief using the oil storage tank.

[0010] Preferably, the transformer housing has through holes on the left and right sides that communicate with the interior of the pressure relief chamber. The piston block moves upward and discharges the air inside the pressure relief chamber through the through holes, maintaining the pressure inside the pressure relief chamber stable. A drain pipe for discharging waste oil inside the pressure relief chamber is fixedly installed on the lower side of the transformer housing.

[0011] Preferably, the lifting mechanism includes a piston block located inside the pressure relief chamber. The piston block and the inner wall of the pressure relief chamber form a close-fitting and sealed sliding structure. As the oil in the pressure relief chamber increases, it pushes the piston block to slide upward. When the oil enters the interior of the pressure relief chamber, the increase in oil pushes the piston block inside the pressure relief chamber to move upward. At this time, the piston block drives the connecting frame to move upward synchronously through the support rod.

[0012] Preferably, a vertically mounted connecting spring is fixedly installed on the upper surface of the piston block. The compression of the connecting spring allows the piston block to have a certain upward movement space. A support rod is fixedly installed on the upper end of the connecting spring. The support rod and the upper end of the pressure relief chamber form a through-type sliding structure. A horizontally arranged connecting frame is fixedly installed on the upper end of the support rod. The connecting frame fixes the connecting pipe on the same side. The piston block drives the connecting frame to move upward synchronously through the support rod. The connecting frame drives the connecting pipe to move upward to the position where it connects with the oil inlet pipe.

[0013] Preferably, a sealing gasket is fixedly installed inside the upper end of the connecting pipe, and the position of the connecting pipe corresponds to the position of the winding coil. Since the connecting pipe is close to the position of the winding coil, it preferentially draws in the oil at the position of the winding coil, so as to achieve the purpose of timely heat dissipation around the winding coil.

[0014] Preferably, the oil inlet pipe is connected to the delivery pump. Under the suction of the delivery pump, the oil inside the transformer tank enters the heat exchanger through the oil inlet pipe. Fixed heat dissipation fins and movable heat dissipation fins are respectively installed on the front and rear sides of the heat exchanger. The movable heat dissipation fins form a through-type sliding structure with the heat exchanger. The heat exchanger is equipped with an installation plate that is fixedly installed with the movable heat dissipation fins. A return spring is fixedly installed between the installation plate and the inner wall of the heat exchanger. By changing the power of the delivery pump, the oil inlet speed of the oil inlet pipe is made greater than the oil outlet speed of the oil outlet pipe. At this time, the internal pressure of the heat exchanger increases. Under the action of pressure, the installation block is pushed to the edge position. At this time, the installation block is used to push the movable heat dissipation fins outward to increase the contact area between the movable heat dissipation fins and the air.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This mine explosion-proof oil-immersed transformer adopts a novel structural design, the specific details of which are as follows: 1. When the pressure inside the transformer tank rises rapidly (such as in the event of a short circuit), the oil expands and flows back to the oil storage tank through the delivery pipe, achieving initial pressure relief. If the oil continues to expand, once the pressure reaches the threshold of the pressure valve, the oil inside the transformer tank enters the pressure relief chamber through the connecting pipe for further pressure relief. Ultimately, the internal pressure of the transformer tank is reduced through two pressure reliefs, achieving the purpose of explosion prevention.

[0016] 2. The oil inside the transformer tank is drawn into the heat exchanger through the oil inlet pipe by the suction action generated by the delivery pump, and then discharged into the transformer tank through the oil outlet pipe below. During this process, the oil is cooled by heat exchange with the air. Furthermore, when the oil enters the pressure relief chamber, the increase in oil volume pushes the piston block inside the pressure relief chamber to move upward. At this time, the piston block drives the connecting frame to move upward synchronously through the support rod. The connecting frame drives the connecting pipe to move upward to the position where it connects with the oil inlet pipe. At this time, the connecting pipe draws in oil. Since the connecting pipe is close to the winding coil, it preferentially draws in the oil at the winding coil position, so as to achieve the purpose of timely heat dissipation around the winding coil. Furthermore, the support rod and piston block are connected by a connecting spring, so after the connecting pipe is connected to the oil inlet pipe, the compression of the connecting spring allows the piston block to have a certain upward movement space.

[0017] 3. By changing the power of the delivery pump, the oil inlet speed of the oil inlet pipe is made greater than the oil outlet speed of the oil outlet pipe. At this time, the internal pressure of the heat exchanger increases. Under the action of pressure, the mounting block is pushed to the edge. Then, the mounting block is used to push the movable heat dissipation fins outward to increase the contact area between the movable heat dissipation fins and the air, thereby achieving a better heat dissipation effect. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the overall exploded structure of the present invention; Figure 3 This is a schematic diagram of the internal structure of the transformer housing of the present invention; Figure 4 This is a schematic diagram of the heat exchanger structure of the present invention; Figure 5 For the present invention Figure 3 Enlarged structural diagram at point A in the middle; Figure 6 This is a schematic diagram of the structure of the oil inlet pipe and the connecting pipe in the separated state of the present invention; Figure 7 This is a schematic diagram of the connection state of the oil inlet pipe and the connecting pipe of the present invention; Figure 8 This is a schematic diagram of the connection relationship between the connecting frame and the piston block of the present invention; Figure 9 This is a schematic diagram of the internal structure of the connecting pipe of the present invention; Figure 10 This is a schematic diagram of the internal structure of the heat exchanger of the present invention; Figure 11 For the present invention Figure 10 Enlarged structural diagram at point B.

[0019] In the diagram: 1. Transformer housing; 2. Winding coil; 3. Mounting bracket; 4. Oil reservoir; 5. Delivery pipe; 6. Pressure relief chamber; 7. Connecting pipe; 8. Pressure valve; 9. Through hole; 10. Drain pipe; 11. Heat exchanger; 12. Oil inlet pipe; 13. Oil outlet pipe; 14. Delivery pump; 15. Connecting pipe; 16. Sealing gasket; 17. Connecting bracket; 18. Support rod; 19. Connecting spring; 20. Piston block; 21. Temperature sensor; 22. Fixed heat dissipation fins; 23. Movable heat dissipation fins; 24. Mounting plate; 25. Return spring. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1: Please refer to Figures 1-5 To achieve the purpose of pressure relief and prevent explosion, this embodiment provides the following technical solution, specifically: a transformer housing 1 with a square structure, a winding coil 2 fixedly installed inside the transformer housing 1 using a mounting bracket 3, pressure relief chambers 6 with a cavity structure on the left and right sides inside the transformer housing 1, the lower end of the pressure relief chamber 6 connected to the inside of the transformer housing 1 through a connecting pipe 7, when the pressure inside the transformer housing 1 reaches the threshold of the pressure valve 8 connected to the connecting pipe 7, the oil in the transformer housing 1 enters the pressure relief chamber 6 through the connecting pipe 7, through holes 9 connected to the inside of the pressure relief chamber 6 are opened on the left and right sides of the transformer housing 1, and a drain pipe 10 for discharging waste oil inside the pressure relief chamber 6 is fixedly installed on the lower side of the transformer housing 1, an oil storage tank 4 is fixedly installed on the upper surface of the transformer housing 1, and the oil storage tank 4 is connected to the inside of the transformer housing 1 through a conveying pipe 5, and a temperature sensor 21 is fixedly installed inside the transformer housing 1.

[0022] When using the device, insulating oil is added to the oil storage tank 4. At this time, the oil in the oil storage tank 4 enters the transformer housing 1 through the delivery pipe 5 until the transformer housing 1 is full of oil. When the oil storage tank 4 is half full, the addition is stopped. At this time, the oil is used to insulate and dissipate heat from the winding coils 2 inside the transformer housing 1. When the temperature inside the transformer housing 1 changes, the oil expands or contracts accordingly. At this time, the oil storage tank 4 is used to replenish the oil inside the transformer housing 1 or the oil in the transformer housing 1 flows back to the oil storage tank 4 to achieve a certain pressure relief effect. If a short circuit occurs inside the transformer housing 1, the temperature rises sharply, causing the oil to expand a lot and exceed the pressure relief capacity of the oil storage tank 4. When the pressure inside the transformer housing 1 reaches the threshold of the pressure valve 8, the oil inside the transformer housing 1 enters the pressure relief chamber 6 through the connecting pipe 7 to achieve the purpose of pressure relief again and prevent the transformer housing 1 from exploding due to excessive pressure.

[0023] Example 2: Please refer to Figures 6-9 To improve heat dissipation while relieving pressure, this embodiment provides the following technical solution: Heat exchangers 11 are fixedly installed on the front and rear sides of the transformer housing 1. Oil inlet pipes 12 and 13, which communicate with the transformer housing 1, are respectively installed at the upper and lower ends of the heat exchangers 11. The oil inlet pipe 12 is connected to a delivery pump 14. Oil inside the transformer housing 1 enters the heat exchanger 11 through the oil inlet pipe 12 under the suction of the delivery pump 14. A connecting pipe 15 is provided inside the transformer housing 1. The connecting pipe 15 changes its oil inlet position by connecting to the oil inlet pipe 12 through lifting mechanisms on the left and right sides inside the transformer housing 1. The lifting mechanism includes a positioning mechanism... Inside the pressure relief chamber 6, there is a piston block 20. The piston block 20 and the inner wall of the pressure relief chamber 6 form a close-fitting and sealed sliding structure. As the oil in the pressure relief chamber 6 increases, it pushes the piston block 20 to slide upward. A vertically installed connecting spring 19 is fixedly installed on the upper surface of the piston block 20. A support rod 18 is fixedly installed on the upper end of the connecting spring 19. The support rod 18 and the upper end of the pressure relief chamber 6 form a through sliding structure. A horizontally arranged connecting frame 17 is fixedly installed on the upper end of the support rod 18. The connecting frame 17 fixes the connecting pipe 15 on the same side. A sealing gasket 16 is fixedly installed inside the upper end of the connecting pipe 15. The position of the connecting pipe 15 corresponds to the position of the winding coil 2.

[0024] When the transformer is in use, the delivery pump 14 connected to the oil inlet pipe 12 is turned on. Under the suction action of the delivery pump 14, the oil inside the transformer tank 1 enters the heat exchanger 11 through the oil inlet pipe 12, and then is discharged back into the transformer tank 1 through the oil outlet pipe 13 below the heat exchanger 11. During this process, the flow of the oil, combined with the heat exchanger 11's metal shell exchanging heat with the air, achieves the purpose of cooling the oil. When depressurizing, the oil inside the transformer tank 1 enters the pressure relief chamber 6. As the oil in the pressure relief chamber 6 increases, it pushes the piston block 20 to move upward. The piston block 20 is made of high-temperature resistant rubber and divides the interior of the pressure relief chamber 6 into two independent spaces, upper and lower. During the upward movement of the piston block 20, the connecting spring 19 pushes the support rod 18 to move upward. The piston block 20 moves upward through the through hole 9. Air is expelled from the pressure relief chamber 6 to maintain stable internal pressure. At this time, the support rod 18 is used to push the connecting frame 17 to move upward synchronously. A sealing ring is set at the penetration position between the support rod 18 and the pressure relief chamber 6 to ensure that the support rod 18 is always sealed with the pressure relief chamber 6 during movement. Finally, the connecting frame 17 drives the connecting pipe 15 to move upward to the position where it connects with the oil inlet pipe 12 to complete the connection with the oil inlet pipe 12. At this time, the delivery pump 14 draws oil from the position of the connecting pipe 15. Since the connecting pipe 15 is close to the winding coil 2, the oil at the position of the winding coil 2 is drawn first to achieve the purpose of concentrated heat dissipation at high temperature positions. After the transformer maintenance is completed, the staff opens the drain pipe 10 valve on the side of the transformer tank 1 to discharge the waste oil that entered the pressure relief chamber 6 during pressure relief. Then, oil is added back into the transformer tank 1.

[0025] Example 3: Please refer to Figures 10-11 This embodiment provides the following technical solution, specifically disclosing that: fixed heat dissipation fins 22 and movable heat dissipation fins 23 are respectively installed on the front and rear sides of the heat exchanger 11, the movable heat dissipation fins 23 and the heat exchanger 11 form a through sliding structure, the heat exchanger 11 is provided with an installation plate 24 fixedly installed with the movable heat dissipation fins 23, and a return spring 25 is fixedly installed between the installation plate 24 and the inner wall of the heat exchanger 11.

[0026] When the temperature sensor 21 detects that the oil temperature inside the transformer tank 1 is higher than the normal set value, it sends a signal to the control device. Then, the power of the delivery pump 14 is increased through the built-in program of the control device, so that the oil inlet speed of the oil inlet pipe 12 is greater than the oil outlet speed of the oil outlet pipe 13. At this time, the oil inside the heat exchanger 11 increases, thereby increasing the pressure inside the heat exchanger 11. The pressure pushes the mounting plate 24 inside the heat exchanger 11 to move to the edge, thereby causing the mounting plate 24 to squeeze out the movable heat dissipation fins 23. The penetration position between the movable heat dissipation fins 23 and the heat exchanger 11 is also provided with a sealing structure, such as a sealing strip structure that is tightly attached to the movable heat dissipation fins 23, to ensure the seal between the movable heat dissipation fins 23 and the heat exchanger 11 when they move. At this time, the movable heat dissipation fins 23 extend to increase the contact area with air and improve the overall heat dissipation effect.

[0027] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A mining explosion-proof oil-immersed transformer, comprising a transformer housing (1) with a square structure, wherein winding coils (2) are fixedly installed inside the transformer housing (1) using mounting brackets (3), characterized in that, Also includes: The transformer housing (1) has a pressure relief chamber (6) with a cavity structure on the left and right sides inside. The lower end of the pressure relief chamber (6) is connected to the inside of the transformer housing (1) through a connecting pipe (7). When the pressure inside the transformer housing (1) reaches the threshold of the pressure valve (8) connected to the connecting pipe (7), the oil in the transformer housing (1) enters the pressure relief chamber (6) through the connecting pipe (7). The transformer housing (1) is fixedly equipped with heat exchangers (11) on the front and rear sides. The upper and lower ends of the heat exchangers (11) are respectively equipped with an oil inlet pipe (12) and an oil outlet pipe (13) that are connected to the transformer housing (1). The transformer housing (1) is equipped with a connecting pipe (15). The connecting pipe (15) is connected to the oil inlet pipe (12) through the lifting mechanism on the left and right sides inside the transformer housing (1) to change the oil inlet position.

2. The explosion-proof oil-immersed transformer for mining as described in claim 1, characterized in that: An oil storage tank (4) is fixedly installed on the upper surface of the transformer housing (1), and the oil storage tank (4) is connected to the inside of the transformer housing (1) through a delivery pipe (5). A temperature sensor (21) is fixedly installed inside the transformer housing (1).

3. The explosion-proof oil-immersed transformer for mining as described in claim 1, characterized in that: The transformer housing (1) has through holes (9) on the left and right sides that communicate with the interior of the pressure relief chamber (6), and a drain pipe (10) for draining waste oil from the interior of the pressure relief chamber (6) is fixedly installed on the lower side of the transformer housing (1).

4. A mining explosion-proof oil-immersed transformer according to claim 1, characterized in that: The lifting mechanism includes a piston block (20) located inside the pressure relief chamber (6). The piston block (20) and the inner wall of the pressure relief chamber (6) form a sliding structure that fits and seals together. The increase of oil in the pressure relief chamber (6) pushes the piston block (20) to slide upward.

5. A mining explosion-proof oil-immersed transformer according to claim 4, characterized in that: A vertically mounted connecting spring (19) is fixedly installed on the upper surface of the piston block (20), and a support rod (18) is fixedly installed on the upper end of the connecting spring (19).

6. A mining explosion-proof oil-immersed transformer according to claim 5, characterized in that: The support rod (18) and the upper end of the pressure relief chamber (6) form a through sliding structure, and a horizontally arranged connecting frame (17) is fixedly installed on the upper end of the support rod (18), and the connecting frame (17) fixes the connecting pipe (15) on the same side.

7. A mining explosion-proof oil-immersed transformer according to claim 6, characterized in that: A sealing gasket (16) is fixedly installed inside the upper end of the connecting pipe (15), and the position of the connecting pipe (15) corresponds to the position of the winding coil (2).

8. A mining explosion-proof oil-immersed transformer according to claim 1, characterized in that: The oil inlet pipe (12) is connected to the delivery pump (14). The oil inside the transformer box (1) enters the heat exchanger (11) through the oil inlet pipe (12) under the suction action of the delivery pump (14).

9. A mining explosion-proof oil-immersed transformer according to claim 8, characterized in that: The heat exchanger (11) has fixed heat dissipation fins (22) and movable heat dissipation fins (23) installed on its front and rear sides respectively. The movable heat dissipation fins (23) and the heat exchanger (11) form a through sliding structure.

10. A mining explosion-proof oil-immersed transformer according to claim 9, characterized in that: The heat exchanger (11) is provided with an installation plate (24) that is fixedly installed with the movable heat dissipation fins (23), and a return spring (25) is fixedly installed between the installation plate (24) and the inner wall of the heat exchanger (11).

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