Electric furnace transformer

Abstract

The utility model discloses an electric furnace transformer, which belongs to the technical field of power transformation electrical equipment and comprises a transformer main body, a cooling oil path connected with the transformer main body and a cooling water path for accelerating heat dissipation of the cooling oil path, a heat exchange area is constructed between the cooling water path and the cooling oil path, and after the cooling oil path takes out heat of the transformer body, the heat is exchanged to the cooling water path; according to the heat exchange area, in the cooling oil way, cooling oil passes through the interior of a heat dissipation pipe, a heat exchange pipe is arranged in the heat dissipation pipe in a penetrating mode, and cooling water flows in the heat exchange pipe. On the basis of oil immersion cooling, the cooling water path and the cooling oil path are arranged for heat exchange, the characteristic of high heat conductivity coefficient of a water medium is fully played, heat in the cooling oil path is rapidly taken away, the heat dissipation effect is improved, and the voltage regulating rectifier transformer can bear large current load and is more suitable for power supply of a large direct current electric furnace.

Description

Technical Field

[0001] The utility model relates to the technical field of power transformation electrical equipment, and more specifically, to an electric furnace transformer. Background Art

[0002] The voltage-regulating rectifier transformer is a power supply device in a large DC furnace. It converts three-phase AC power through a voltage-regulating rectifier transformer, and then forms single-phase DC power through a thyristor rectifier. It generates an arc on the metal charge between the bottom electrode (anode) and the graphite electrode (cathode) of the large DC furnace for smelting. Compared with AC arc furnaces, large DC furnaces use voltage-regulating rectifier transformers to reduce current and voltage fluctuations, reduce impact on the power grid, and extend the life of the cable. In order to meet the needs of high-power and high-efficiency smelting, large DC furnaces usually have very high rated currents. The total current of some furnace equipment can reach hundreds of kiloamperes (kA) or even higher, and the voltage-regulating rectifier transformers that power them are also affected by the increased heat generated by the large current. Usually, transformers dissipate heat through a heat sink structure. For example, the Chinese patent with announcement number CN108766727A discloses an electric furnace transformer, which includes a housing, a fixing seat and an oil tank; heat sink fins are arranged on both sides of the fixing seat, and fans are installed in the center of the heat conducting plates installed at both ends of the oil tank, so that the heat in the oil during the oil cooling process is transferred to the heat conducting plates, and the heat on the heat conducting plates is blown to the heat dissipation fins by the fan to achieve the purpose of heat dissipation. However, the heat dissipation of this oil-immersed air-cooled structure is still insufficient, and the structure needs to be further optimized to improve the heat dissipation effect. Utility Model Content

[0003] In view of the above problems, the purpose of the utility model is to provide an electric furnace transformer with improved heat dissipation structure and enhanced heat dissipation effect, which is more suitable for powering large DC electric furnaces.

[0004] In order to achieve these purposes of the utility model, the utility model provides an electric furnace transformer, comprising: a transformer body, a cooling oil circuit connected to the transformer body, and a cooling water circuit for accelerating heat dissipation of the cooling oil circuit;

[0005] A heat exchange area is constructed between the cooling water circuit and the cooling oil circuit. After the cooling oil circuit takes out the heat of the transformer body, the heat is exchanged to the cooling water circuit to improve the heat dissipation effect.

[0006] Different from the oil-immersed self-cooling and oil-immersed air-cooling in the traditional technology, the utility model sets a cooling water circuit and a cooling oil circuit for heat exchange on the basis of oil-immersed cooling, giving full play to the high thermal conductivity of the water medium, quickly taking away the heat in the cooling oil circuit, improving the heat dissipation effect, and enabling the voltage regulating rectifier transformer to withstand the large current load of power supply for large DC furnaces.

[0007] Preferably, the heat exchange area is constructed as follows: in the cooling oil circuit, the cooling oil passes through the inside of the heat dissipation tube, and the heat is dissipated outwardly through the heat dissipation tube, forming an external heat dissipation structure, and a heat exchange tube is arranged inside the heat dissipation tube, and the cooling water flows from the inside of the heat exchange tube, and the heat of the cooling oil is transferred to the cooling water through the heat exchange tube, thereby forming an internal heat dissipation structure, and the external heat dissipation structure is combined with the internal heat dissipation structure to improve the heat dissipation speed and effect.

[0008] Preferably, the heat exchange tube is passed through the heat dissipation tube in a spiral structure or a zigzag structure, which increases the length and heat exchange area compared to passing through the heat dissipation tube in a straight line, thereby improving the heat dissipation effect.

[0009] Preferably, the flow direction of the cooling oil in the heat dissipation pipe is opposite to the flow direction of the cooling water in the heat exchange pipe.

[0010] Preferably, the outer wall of the heat dissipation pipe is provided with heat dissipation fins to improve the heat dissipation effect outside the heat dissipation pipe.

[0011] Preferably, the heat dissipation pipes are fixed on the support frame and arranged into several layers in the height direction and connected end to end in sequence; the heat dissipation fins are supported in the interval space between adjacent heat dissipation pipes, which can not only accelerate the heat dissipation but also support the multi-layer heat dissipation pipes stably.

[0012] Preferably, buffer boxes are provided on both sides of the support frame respectively, and the oil from the transformer body direction first enters the buffer box and then enters the heat dissipation pipe, and the cooling oil output by the heat dissipation pipe first enters the buffer box and then is sent back to the transformer body.

[0013] Preferably, in addition to the heat exchange tubes passing through the heat dissipation pipes, the cooling water circuit is also provided with a water radiator, a water tank and a water circulation pump. The cooling water in the heat exchange tubes dissipates heat through the water radiator, then enters the water tank, and is then returned to the heat exchange tubes by the water circulation pump to form a cycle.

[0014] Preferably, a fan is provided to cool the heat dissipation pipe and the heat exchange pipe.

[0015] The utility model at least has the following beneficial effects:

[0016] 1. On the basis of oil immersion cooling, the utility model sets a cooling water circuit and a cooling oil circuit for heat exchange, giving full play to the high thermal conductivity of the water medium, quickly taking away the heat in the cooling oil circuit, improving the heat dissipation effect, so that the voltage regulating rectifier transformer can withstand the heat dissipation load brought by the large current and is more suitable for powering large DC furnaces.

[0017] 2. In the cooling oil circuit of the utility model, the cooling oil passes through the inside of the heat dissipation pipe, and the heat is dissipated outward through the heat dissipation pipe, forming an external heat dissipation structure. A heat exchange pipe is arranged inside the heat dissipation pipe, and the cooling water flows through the inside of the heat exchange pipe. The heat of the cooling oil is transferred to the cooling water through the heat exchange pipe, thereby forming an internal heat dissipation structure. The external heat dissipation structure is combined with the internal heat dissipation structure to improve the heat dissipation speed and effect, and effectively solve the problem of slow heat dissipation of traditional transformer oil-immersed self-cooling and oil-immersed air cooling.

[0018] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a front structural schematic diagram of the electric furnace transformer of the utility model;

[0020] Figure 2 It is a schematic diagram of the top view of the electric furnace transformer of the utility model;

[0021] Figure 3 A schematic diagram of the structure of the heat exchange area of ​​the utility model;

[0022] Figure 4 It is a schematic diagram of the flow direction of cooling oil in the heat exchange area of ​​the heat dissipation pipe of the utility model;

[0023] Figure 5 It is a schematic diagram of the connection structure of the water radiator, water tank and water circulation pump in the cooling water circuit of the utility model. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below with reference to examples so that those skilled in the art can implement the invention with reference to the description.

[0025] It should be understood that terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0026] like Figures 1 to 4 As shown, an electric furnace transformer of the utility model comprises: a transformer body 10, a cooling oil circuit 30 connected to the transformer body 10, and a cooling water circuit 40 for accelerating heat dissipation of the cooling oil circuit 30;

[0027] A heat exchange area 34 is constructed between the cooling water circuit 40 and the cooling oil circuit 30 . After the cooling oil circuit 30 takes out the heat of the transformer body 10 , the heat is exchanged to the cooling water circuit 40 .

[0028] like Figure 1 and 2As shown, an oil pillow 20 is arranged above the transformer body 10, and the oil pillow 20 is connected to the transformer body 10. The transformer body 10 includes a box body and an iron core, a winding, etc. located inside the box body. The iron core and the winding are immersed in cooling oil. The cooling oil plays the role of insulation and heat dissipation. The heat generated by the iron core and the winding is absorbed by the cooling oil.

[0029] In the cooling oil circuit 30 of the figure, the oil inlet section 301 is connected to the top of the transformer body 10, and the cooling oil carrying heat enters the oil inlet section 301 from the transformer body 10, is connected to the circulating oil pump 302, and then enters the heat exchange area 34 through the oil inlet 303. After heat exchange, it is output from the oil outlet 304 and returned to the transformer body 10 through the return oil pipe 305. In the figure, the return oil pipe 305 is connected to a position near the bottom of the transformer body 10.

[0030] In the cooling water circuit 40 of the figure, cooling water enters the circulating water pump 402 from the water tank 403, and then enters the heat exchange area through the water inlet 401. After heat exchange, it is output from the water outlet 405, and through the pipeline, it is connected to the water medium radiator 409 from the return water port 404 for heat dissipation and cooling, and then returns to the water tank.

[0031] In the heat exchange area, the cooling water circuit 40 and the cooling oil circuit 30 are constructed as overlapping, socketed, and contacting structures, so that the cooling oil and the cooling water can exchange heat and achieve the purpose of heat dissipation and transfer in the cooling oil. Since water has high thermal conductivity and high specific heat capacity, it can dissipate heat quickly and effectively.

[0032] Different from the oil-immersed self-cooling and oil-immersed air-cooling in the traditional technology, this implementation scheme sets up a cooling water circuit and a cooling oil circuit for heat exchange on the basis of oil-immersed cooling, giving full play to the high thermal conductivity of the water medium, quickly taking away the heat in the cooling oil circuit, improving the heat dissipation effect, and enabling the voltage regulating rectifier transformer to withstand the large current load of power supply for large DC furnaces.

[0033] Further, in another embodiment, Figure 3 As shown, the heat exchange area is constructed as follows: in the cooling oil circuit 30, the cooling oil passes through the inside of the heat dissipation tube 309, and the heat is dissipated outwards through the heat dissipation tube 309, forming an external heat dissipation structure, and a heat exchange tube 410 is passed through the inside of the heat dissipation tube 309, and the cooling water flows from the inside of the heat exchange tube 410. The heat of the cooling oil is transferred to the cooling water through the heat exchange tube 410, thereby forming an internal heat dissipation structure. The external heat dissipation structure is combined with the internal heat dissipation structure to improve the heat dissipation speed and effect. The traditional transformer oil-immersed self-cooling and oil-immersed air-cooling structures only have an external heat dissipation structure, and the heat carried by the cooling oil can only be dissipated outwards, naturally dissipated or accelerated by the wind. The utility model adopts a combination of an external heat dissipation structure and an internal heat dissipation structure, and the heat dissipation speed and effect are better. For ease of understanding, combined with Figure 3To explain in more detail, the cooling oil enters the first buffer tank 306 from the oil inlet 303, then enters the heat pipe from the heat pipe inlet 308, passes through layers of heat pipes connected end to end, and a heat exchange pipe 410 is passed through the heat pipe 309. The cooling oil exchanges heat with the heat exchange pipe, and the heat is taken away by the cooling water flowing inside the heat exchange pipe. The cooling oil is then output from the heat pipe outlet 311 to the second buffer tank 312, and finally output from the oil outlet 304.

[0034] Further, if Figure 3 As shown, the heat exchange tube 410 is arranged in a spiral structure or a zigzag structure through the heat exchange tube. Compared with a straight line through the heat exchange tube, the length is increased and the heat exchange area is increased, thereby improving the heat dissipation effect. In the figure, the heat exchange tube is preferably a spiral structure, which is arranged inside the heat exchange tube, with a larger heat exchange area and better heat dissipation effect. In the figure, several layers of heat exchange tubes are connected in series, and cooling water enters from the water inlet 401 and is finally output from the water outlet 405.

[0035] Preferably, Figure 3 and Figure 4 As shown, the flow direction of the cooling oil in the heat dissipation pipe 309 is opposite to the flow direction of the cooling water in the heat exchange pipe 410, which can achieve higher heat exchange efficiency.

[0036] Further, in another embodiment, Figure 3 and Figure 4 As shown, heat dissipation fins 310 are provided on the outer wall of the heat dissipation pipe 309, which increases the heat dissipation area outside the heat dissipation pipe and improves the heat dissipation effect outside the heat dissipation pipe.

[0037] Further, in another embodiment, more specifically, Figure 3 and Figure 4 As shown, both ends of the heat dissipation pipe 309 are fixed on the support frame 307, and are arranged in a plurality of layers in the height direction, and are connected end to end in sequence; the heat dissipation fins 310 are supported in the interval between adjacent heat dissipation pipes, which can not only accelerate the heat dissipation, but also support the multi-layer heat dissipation pipe 309 stably. In the example, the heat dissipation pipes 309 of the upper and lower adjacent layers are connected at the end to the end through an arc segment, and the arc segment is fixed to the heat dissipation pipe by welding, or fixed by sleeve connection for easy disassembly and assembly, or is an integrated structure.

[0038] Further, in another embodiment, Figure 3 and Figure 4As shown, the first buffer box 306 and the second buffer box 312 are respectively arranged on both sides of the support frame 307. The oil from the transformer body direction first enters the first buffer box 306, and then enters the heat dissipation pipe 309. The cooling oil output by the heat dissipation pipe 309 first enters the second buffer box 312, and then is sent back to the transformer body 10. In the example, the oil inlet 303 is arranged at the upper part of the first buffer box 306, the heat dissipation pipe inlet 308 is connected to the position close to the lower part of the first buffer box 306, the heat dissipation pipe outlet 311 enters the second buffer box from the upper part, and the oil outlet 304 is arranged at the lower part of the second buffer box. The lower parts of the first buffer box 306 and the second buffer box 312 are also provided with an inspection port 313 to facilitate slag removal and maintenance operations.

[0039] Further, in another embodiment, Figure 1 , Figure 2 and Figure 5 As shown, in the cooling water circuit, in addition to the heat exchange tube 410 passing through the heat dissipation tube 309, a water radiator 409, a water tank 403 and a water circulation pump 402 are also provided. The cooling water of the heat exchange tube 410 dissipates heat through the water radiator 409, then enters the water tank 403, and then is sent back to the heat exchange tube 410 by the water circulation pump 402 to form a cycle. In the legend, the water radiator 409 includes: a fixing frame 408, a box body 407, and a metal pipe 406. The fixing frame 408 is located on both sides to fix the metal pipe. The cooling water of the heat exchange tube 410 is connected to the left box body, and then enters the metal pipe 406. Several layers of metal pipes are connected in sequence. The cooling water dissipates heat outward through the metal pipe and is cooled, then enters the water tank on the right, and finally enters the water tank 403.

[0040] Further, in another embodiment, Figure 1 As shown, a fan 50 is provided to blow air to cool the heat exchange area 34. Figure 1 As shown, the heat exchange area 34 and the water channel radiator 409 are arranged in a row, and the fan 50 blows air from one side of the heat exchange area 34. After the wind passes through the heat dissipation fins 310, it continues to cool the water channel radiator 409, thereby improving the wind utilization effect.

[0041] A more specific implementation process of the utility model is as follows:

[0042] The circulating oil pump 302 is started, and the cooling oil carrying heat enters the incoming oil section 301 from the transformer body 10, passes through the circulating oil pump 302, and enters the heat exchange area 34 through the oil inlet 303. After heat exchange, it is output from the oil outlet 304 and returned to the transformer body 10 through the return oil pipe 305, forming a cooling oil circuit circulation.

[0043] Start the circulating water pump 402, and the cooling water flows from the water tank 403 through the circulating water pump 402 and enters the heat exchange area through the water inlet 401. After heat exchange, the cooling water is output from the water outlet 405, and is connected to the water medium radiator 409 from the return water inlet 404 through the pipeline for heat dissipation and cooling, and then returns to the water tank 430 to form a cooling water circuit circulation.

[0044] In the heat exchange area 34, the heat exchange tube 410 is arranged in a spiral structure in the heat dissipation tube 309, and the cooling water flow direction of the heat exchange tube is opposite to the cooling oil flow direction in the heat dissipation tube, so that the cooling oil dissipates heat outward and the internal heat exchange is carried out simultaneously. The fan is started to provide airflow to accelerate the heat dissipation and cooling of the heat exchange area 34 and the water radiator 409.

[0045] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and the embodiments. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily realized.

Claims

1. An electric furnace transformer, characterized in that: include: The transformer body, a cooling oil circuit connected to the transformer body, and a cooling water circuit for accelerating heat dissipation of the cooling oil circuit; A heat exchange area is constructed between the cooling water circuit and the cooling oil circuit. After the cooling oil circuit takes out the heat of the transformer body, the heat is exchanged to the cooling water circuit. The heat exchange area is constructed as follows: in the cooling oil circuit, cooling oil passes through the inside of the heat dissipation tube, and a heat exchange tube is arranged inside the heat dissipation tube, and cooling water flows through the inside of the heat exchange tube.

2. The electric furnace transformer according to claim 1, characterized in that: The heat exchange tube is passed through the heat dissipation tube in a spiral structure or a zigzag structure.

3. The electric furnace transformer according to claim 1, characterized in that: The flow direction of the cooling oil in the heat dissipation pipe is opposite to the flow direction of the cooling water in the heat exchange pipe.

4. The electric furnace transformer according to claim 1, characterized in that: The outer wall of the heat dissipation pipe is provided with heat dissipation fins for improving the heat dissipation effect outside the heat dissipation pipe.

5. The electric furnace transformer according to claim 4, characterized in that: The heat dissipation pipes are fixed on the support frame and arranged in several layers in the height direction and connected end to end in sequence; the heat dissipation fins are supported in the intervals between adjacent heat dissipation pipes, which can not only accelerate the heat dissipation but also support the multi-layer heat dissipation pipes stably.

6. The electric furnace transformer according to claim 5, characterized in that: Buffer boxes are respectively arranged on both sides of the support frame. The oil from the transformer main body first enters the buffer box and then enters the heat dissipation pipe. The cooling oil output by the heat dissipation pipe first enters the buffer box and then is sent back to the transformer main body.

7. The electric furnace transformer according to claim 1, characterized in that: In addition to the heat exchange tubes passing through the heat dissipation pipes, the cooling water circuit is also provided with a water circuit radiator, a water tank and a water circuit circulation pump. The cooling water in the heat exchange tubes dissipates heat through the water circuit radiator, then enters the water tank, and is then returned to the heat exchange tubes by the water circuit circulation pump to form a cycle.

8. The electric furnace transformer according to claim 1, characterized in that: A fan is also provided to blow air to the heat exchange area to dissipate heat.

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