Direct expansion type transformer cooling structure based on heat pump principle

Abstract

The invention provides a direct expansion type transformer cooling structure based on a heat pump principle, which comprises a refrigerant, a compressor, a heat exchanger, an expansion valve, a hollow wire and an insulation pipe fitting, the refrigerant is connected with the heat exchanger through a pipeline, the refrigerant is connected with a liquid inlet end of the compressor through a pipeline, a liquid outlet end of the compressor is connected with the heat exchanger through a pipeline, and the heat exchanger is connected with the expansion valve through a pipeline. A pipeline penetrating through the heat exchanger is connected with an insulation pipe fitting, an expansion valve is installed on the pipeline, and the insulation pipe fitting is connected with a hollow wire. The heat pump principle and the transformer internal cooling technology are combined, the cooling effect is achieved through phase change of refrigerants, and meanwhile the safety of electrical parts is ensured through insulating materials. According to the design, the cooling efficiency of the transformer or other electrical equipment can be improved, overheating is prevented, and the performance and reliability of the equipment are improved. Due to the use of the hollow wire, a pipeline in which a refrigerant flows is insulated from and separated from an electrical part, so that the safe operation of a system is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of transformers, and in particular to a direct expansion transformer cooling structure based on a heat pump principle. Background Art

[0002] Transformers, as an indispensable device in power systems, have a core working principle based on electromagnetic induction. This device increases or decreases the voltage through electromagnetic induction between the primary coil and the secondary coil. The main components of the transformer include the primary coil, the secondary coil and the core (magnetic core). The primary coil is responsible for receiving the input AC voltage, while the secondary coil outputs the adjusted voltage. The core, as a carrier of magnetic flux, connects the two coils to ensure the effective transfer of electromagnetic energy.

[0003] During operation, the coils and cores in the transformer generate a lot of heat. This is because when current passes through the coil, according to Joule's law, it will generate resistance heat that is proportional to the square of the current. The greater the current, the greater the resistance of the wire, and the more obvious the voltage drop that comes with it. This voltage drop will cause electrical energy to be converted into heat energy. If the temperature is too high, it may damage the insulation material of the transformer and even cause safety accidents such as fire.

[0004] In order to obtain a larger current, it is usually necessary to increase the number of turns of the coil. However, increasing the number of turns will cause the volume and weight of the transformer to increase significantly. This increase in volume and weight poses a significant limitation for some application scenarios, such as fast charging systems for new energy vehicles and resistance welding equipment. In these applications, the volume and weight of the transformer directly affect the portability, installation space, and overall performance of the equipment. Summary of the invention

[0005] In view of the above technical problems, the present invention provides a direct expansion transformer cooling structure based on the heat pump principle, which is characterized by comprising a refrigerant, a compressor, a heat exchanger, an expansion valve, a hollow wire, and an insulating pipe fitting. The refrigerant is connected to the heat exchanger through a pipeline, the refrigerant is connected to the liquid inlet end of the compressor through a pipeline, the liquid outlet end of the compressor is connected to the heat exchanger through a pipeline, the pipeline passing through the heat exchanger is connected to the insulating pipe fitting, an expansion valve is installed on the pipeline, and the insulating pipe fitting is connected to the hollow wire.

[0006] The hollow conduit is wound around the core of the transformer.

[0007] The hollow conduit is filled with refrigerant.

[0008] A fin heat exchanger is arranged at the heating end of the compressor, and the heat generated by the compressor is utilized. The fin heat exchanger improves the heat dissipation efficiency by increasing the surface area.

[0009] The refrigerant is a cooling medium.

[0010] The fin heat exchanger is connected to a fan.

[0011] The cooling method of direct expansion transformer based on the heat pump principle is:

[0012] (1) The transformer generates heat during operation. The hollow wire wrapped around the upper side of the transformer core is filled with refrigerant, which absorbs the heat emitted by the hollow wire. After the absorption is completed, the refrigerant inside enters the radiator through the hollow wire, insulating pipe fittings, and conveying pipes. The radiator is connected to the fan, and the radiator and the fan dissipate the heat of the refrigerant.

[0013] (2) The compressor compresses the refrigerant inside the delivery pipeline. The refrigerant is discharged from the compressor as a high-temperature and high-pressure liquid; the refrigerant is compressed from a low-pressure gas state to a high-pressure gas, thereby promoting the circulation of the refrigerant in the system;

[0014] (3) The compressed refrigerant enters the hollow wire wrapped around the transformer core through the expansion valve and insulating pipe fittings. The refrigerant absorbs the heat generated by the hollow wire and evaporates, cooling the coil to achieve the purpose of cooling.

[0015] (4) The refrigerant is transported along the hollow wire and enters the insulating pipes and heat exchangers again for recycling.

[0016] Heat pump principle: A heat pump is a device that transfers heat from a low-temperature heat source to a high-temperature heat source through a reverse thermodynamic cycle. In this system, the working principle of the heat pump is applied to both cooling and heating.

[0017] Transformer internal cooling technology: This refers to the technology of using hollow conductors as cooling media. Refrigerant can flow inside the hollow conductors, thereby achieving cooling in the conductors.

[0018] Fin heat exchanger: A fin heat exchanger is installed at the heating end of the compressor to utilize the heat generated by the compressor. The fin heat exchanger increases the efficiency of heat dissipation by increasing the surface area.

[0019] Change of state of refrigerant: The compressor compresses the refrigerant into a high-temperature and high-pressure liquid.

[0020] When the refrigerant is discharged from the compressor, it passes through the expansion valve and into the hollow wire, where the pressure and temperature of the refrigerant are reduced to form a liquid.

[0021] The refrigerant absorbs heat inside the wire, evaporates into gas, and takes away the heat generated by the wire, thereby cooling the coil.

[0022] Insulating material pipe connection: The refrigerant inlet and outlet are connected by pipes made of insulating material, which can ensure that the flow of refrigerant does not interfere with the connection of the circuit. The use of insulating material is to prevent the flow of electric current through the refrigerant system, thereby ensuring the safety of the equipment.

[0023] The compressor pushes the refrigerant to circulate in the system.

[0024] A coil is arranged inside the wire, and the heat inside the wire comes from the internal coil of the transformer. The beneficial effects of the present invention are as follows: the present invention utilizes the heat pump principle, adopts transformer internal cooling technology, i.e., hollow wire, and arranges a fin heat exchanger at the heating end of the compressor to utilize or dissipate the generated heat. At this time, the high-temperature and high-pressure liquid discharged from the compressor by the refrigerant becomes a liquid with a lower temperature, and enters the wire through the expansion valve. The refrigerant absorbs the heat generated by the wire and evaporates, cooling the coil to achieve the purpose of cooling. The refrigerant inlet and outlet are connected by pipe fittings made of insulating materials, which does not affect the input and output circuit connection.

[0025] The present invention combines the heat pump principle and transformer internal cooling technology, uses the phase change of the refrigerant to achieve the cooling effect, and at the same time ensures the safety of the electrical part through the insulating material. This design can improve the cooling efficiency of the transformer or other electrical equipment, prevent overheating, and improve the performance and reliability of the equipment.

[0026] The use of the hollow conductor of the present invention keeps the pipes through which the refrigerant flows insulated and separated from the electrical parts to ensure the safe operation of the system. This design is to prevent the influence of electrical failure on the flow of the refrigerant and ensure the safety and effectiveness of the equipment.

[0027] The use of insulating pipes ensures the safety of the present application. During the flow of the refrigerant, the relevant pipes or components such as the input and output of the compressor are not directly connected to the power supply. In other words, the flow of the refrigerant is separated from the electrical part to prevent the current from passing through the refrigerant pipe or affecting the flow of the refrigerant.

[0028] The present invention can effectively prolong the service life of the transformer, reduce power loss, reduce the size of the transformer, and facilitate various applications.

[0029] The present invention can also use the cooling end in the form of a cooling fan to cool the dry-type transformer, and can also use heat exchange with transformer oil to cool the immersed transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is an implementation diagram of the present invention. DETAILED DESCRIPTION

[0031] Example 1

[0032] The present invention provides a direct expansion transformer cooling structure based on the heat pump principle, characterized in that it includes a refrigerant, a compressor, a heat exchanger, an expansion valve, a hollow conductor, and an insulating pipe fitting. The refrigerant is connected to the heat exchanger through a pipeline, the heat exchanger is connected to the liquid inlet end of the compressor through a pipeline, the liquid outlet end of the compressor is connected to the insulating pipe fitting through a pipeline, the expansion valve is installed on the pipeline, and the insulating pipe fitting is connected to the hollow conductor. The hollow conductor is wrapped around the outside of the coil. A fin heat exchanger is provided at the heating end of the compressor to utilize the heat generated by the compressor. The fin heat exchanger improves the heat dissipation efficiency by increasing the surface area. The refrigerant is a refrigerant.

[0033] The invention relates to an innovative transformer cooling structure, which is based on the working principle of a heat pump and aims to improve the heat dissipation performance and energy efficiency ratio of the transformer.

[0034] In this cooling structure, the refrigerant is used as the main working medium and is connected to the heat exchanger through a pipe to achieve heat exchange. The pipe passing through the heat exchanger is connected to the liquid inlet of the compressor, thereby ensuring that the refrigerant is compressed inside the compressor. The liquid outlet of the compressor is connected to the insulating pipe through a pipe, and the compressed refrigerant is output from the compressor. An expansion valve is installed on the pipe to control the flow and pressure of the refrigerant, so that the refrigerant can better enter the insulating pipe and the hollow wire. The refrigerant absorbs the heat in the wire and evaporates, cooling the coil to achieve the purpose of cooling.

[0035] In a specific implementation process, the hollow wire is wrapped around the outside of the coil of the transformer, which helps to improve the heat dissipation effect of the transformer.

[0036] In the present invention, the refrigerant is a cooling medium having excellent thermal conductivity and heat exchange capacity. During the circulation process, the cooling medium can fully absorb the heat generated by the transformer and transfer it to the outside, thereby achieving effective cooling of the transformer.

[0037] Example 2

[0038] The direct expansion transformer cooling method based on the heat pump principle is an efficient and energy-saving transformer cooling technology. Its working process is as follows:

[0039] (1) A hollow conductor is set outside the transformer coil and filled with refrigerant. When the transformer is running, the heat generated by the coil will be absorbed by the refrigerant in the hollow conductor. This process is achieved through heat conduction between the refrigerant and the coil. As the heat is continuously transferred, the refrigerant in the hollow conductor gradually absorbs the heat of the transformer core and the wall of the hollow conductor.

[0040] (2) The refrigerant that has absorbed the heat is then transported to the compressor through insulating pipes and delivery pipes. After the absorption is completed, the internal refrigerant enters the radiator through the hollow wire, insulating pipes, and delivery pipes. The radiator is connected to the fan, and the radiator and the fan dissipate the heat of the refrigerant;

[0041] (3) The compressor compresses the refrigerant inside the delivery pipeline. The refrigerant is discharged from the compressor as a high-temperature and high-pressure liquid. The refrigerant is compressed from a low-pressure gas state to a high-pressure gas. This liquid has a high latent heat and can effectively absorb and release heat. The compressor thus drives the refrigerant to circulate in the system;

[0042] (4) The compressed refrigerant enters the hollow wire wound around the transformer core through the expansion valve and insulating pipe fittings. The refrigerant absorbs the heat generated by the hollow wire and evaporates, cooling the coil to achieve the purpose of cooling. The lower temperature liquid then enters the hollow wire through the expansion valve. Inside the wire, the refrigerant absorbs the heat in the side wall of the hollow wire, undergoes a phase change, and evaporates from liquid to gas. In this process, the refrigerant absorbs the heat from the side wall of the hollow wire and the transformer core, causing the temperature of the hollow wire to drop, thereby achieving the purpose of cooling the coil.

[0043] (5) The refrigerant is transported along the hollow wire and enters the insulating pipe and heat exchanger again for recycling.

[0044] Specifically, the following are the detailed steps of the cooling method:

[0045] The refrigerant circulates inside the hollow conductor with the transformer core, continuously absorbing the heat from the side walls of the hollow conductor and the transformer core to form a high-temperature liquid.

[0046] The high-temperature liquid enters the fin heat exchanger through the delivery pipe, exchanges heat with the fin heat exchanger and the external air, releases heat, and the temperature of the liquid refrigerant decreases. The refrigerant with reduced temperature enters the compressor and is compressed into a liquid with higher temperature and pressure.

[0047] High-temperature and high-pressure liquid enters the expansion valve through the pipeline, and the refrigerant expands in the expansion valve. The expanded refrigerant enters the hollow conductor wrapped around the iron core through the insulating pipe fittings. At this time, the refrigerant absorbs heat and releases cold, cooling the side wall of the hollow conductor, thereby cooling the side wall of the hollow conductor and the iron core.

[0048] The cooled refrigerant is sucked in again due to the action of the compressor, and the cycle repeats to continue the cooling process.

[0049] This direct expansion transformer cooling method can not only effectively reduce the temperature of the transformer and improve its operating efficiency, but also reduce energy consumption. It is an environmentally friendly and energy-saving cooling technology.

[0050] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. The various components mentioned in the present invention are common technologies in the existing field. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only to illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A direct expansion transformer cooling structure based on the heat pump principle, characterized in that The invention comprises a refrigerant, a compressor, a heat exchanger, an expansion valve, a hollow wire and an insulating pipe fitting. The refrigerant is connected to the heat exchanger through a pipeline, the refrigerant is connected to the liquid inlet of the compressor through a pipeline, the liquid outlet of the compressor is connected to the heat exchanger through a pipeline, the pipeline passing through the heat exchanger is connected to the insulating pipe fitting, an expansion valve is installed on the pipeline, and the insulating pipe fitting is connected to the hollow wire.

2. A direct expansion transformer cooling structure based on the heat pump principle according to claim 1, characterized in that The hollow conduit is wound around the core of the transformer.

3. A direct expansion transformer cooling structure based on the heat pump principle according to claim 1, characterized in that The hollow conduit is filled with refrigerant.

4. A direct expansion transformer cooling structure based on the heat pump principle according to claim 1, characterized in that A fin heat exchanger is arranged at the heating end of the compressor, and the heat generated by the compressor is utilized. The fin heat exchanger improves the heat dissipation efficiency by increasing the surface area.

5. A direct expansion transformer cooling structure based on the heat pump principle according to claim 1, characterized in that The refrigerant is a cooling medium.

6. A direct expansion transformer cooling structure based on the heat pump principle according to claim 1, characterized in that The fin heat exchanger is connected to a fan.

7. A direct expansion transformer cooling structure based on the heat pump principle according to claim 1, characterized in that The cooling method of direct expansion transformer based on the heat pump principle is: (1) The transformer generates heat during operation. The hollow wire wrapped around the upper side of the transformer core is filled with refrigerant, which absorbs the heat emitted by the hollow wire. After the absorption is completed, the refrigerant inside enters the radiator through the hollow wire, insulating pipe fittings, and conveying pipes. The radiator is connected to the fan, and the radiator and the fan dissipate the heat of the refrigerant. (2) The compressor compresses the refrigerant inside the delivery pipeline. The refrigerant is discharged from the compressor as a high-temperature and high-pressure liquid; the refrigerant is compressed from a low-pressure gas state to a high-pressure gas, thereby promoting the circulation of the refrigerant in the system; (3) The compressed refrigerant enters the hollow wire wrapped around the transformer core through the expansion valve and insulating pipe fittings. The refrigerant absorbs the heat generated by the hollow wire and evaporates, cooling the coil to achieve the purpose of cooling. (4) The refrigerant is transported along the hollow wire and enters the insulating pipe and heat exchanger again for recycling.

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