Transformer waste heat recovery system based on heat pipe heat exchange

Abstract

The invention discloses a transformer waste heat recovery system based on heat pipe heat exchange. The transformer waste heat recovery system is used for achieving two waste heat absorption modes of heat supply in a heat supply season and cold water preheating in a non-heat supply season. Comprising a transformer, a heat pipe exchanger, a water storage tank and a change-over valve, the heat pipe heat exchanger comprises an evaporation section and a condensation section; the transformer is communicated with the heat pipe heat exchanger through a pipeline to form heat conduction oil circulation, the heat pipe heat exchanger is communicated with the regulation and storage water tank through a pipeline to form primary water circulation, and the regulation and storage water tank is communicated with the change-over valve through a pipeline to form secondary water circulation. The change-over valve is connected with a heating user and hot water equipment through pipelines; the heat conduction oil circulation is used for transferring waste heat generated by a transformer to an evaporation section of the heat pipe heat exchanger through heat conduction oil, the primary water circulation absorbs heat through a condensation section of the heat pipe heat exchanger, hot water is conveyed to the water storage regulation tank and then is connected with the secondary water circulation through the water storage regulation tank, and the secondary water circulation transfers the heat to heating users.

Description

Technical Field

[0001] The invention patent relates to the field of waste heat recovery and heating, and in particular to a transformer waste heat recovery system based on heat pipe heat exchange. Background Art

[0002] Substations are important hubs in the power system. During operation, transformer equipment will generate losses, and part of the electrical energy will be converted into heat and dissipated. The accumulation of heat will cause the equipment temperature to rise, which will affect the safe use of transformer equipment. At present, in response to the heat generation and temperature rise of transformer equipment during operation, refrigeration and air conditioning are mostly used for cooling. This method of directly discharging the heat generated by the transformer into the atmosphere through refrigeration and air conditioning not only brings about higher air conditioning operation costs, but also wastes thermal energy resources to a certain extent.

[0003] The existing transformer waste heat recovery system is mainly based on ordinary heat exchangers and heat pumps. Although the former has the advantages of simple and convenient equipment and operation, it cannot achieve high heat exchange efficiency under the condition of low-temperature heat source, and it is very likely that it will not be able to guarantee the normal heat exchange needs of the transformer. The latter is the main method of utilizing low-temperature heat sources at present. It can improve the quality of low-temperature heat sources and increase the utilization potential of heat sources, but the heat pump system is relatively complex in equipment and operation.

[0004] Existing transformer waste heat recovery systems rarely consider the system's year-round heat disposal plan. Due to seasonal differences in ambient temperature, the transformer's oil outlet temperature will fluctuate seasonally, which causes the temperature of the hot water after heat exchange to also fluctuate seasonally. Therefore, different heat disposal plans need to be specified for different seasons to achieve efficient and stable heat disposal to ensure normal heat dissipation of the transformer equipment throughout the year. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art, solve the problem of waste heat of transformer equipment in the power system, improve the traditional transformer equipment heat dissipation mode and the existing transformer waste heat utilization mode, and provide a transformer waste heat recovery system based on heat pipe heat exchange. The present invention formulates a seasonal heat absorption mode that can respond to seasonal changes in view of the seasonal changes of the waste heat itself, so as to realize the efficient utilization of the waste heat of the transformer equipment across seasons, which not only reduces the operating cost of the air conditioning heat dissipation of the traditional transformer equipment, but also brings additional economic benefits to the transformer station.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A transformer waste heat recovery system based on heat pipe heat exchange, characterized in that it is used to realize two waste heat consumption modes: heating in the heating season and cold water preheating in the non-heating season; comprising a transformer, a heat pipe heat exchanger, a regulating water storage tank, and a conversion valve; the heat pipe heat exchanger comprises an evaporation section and a condensation section;

[0008] The transformer is interconnected with the heat pipe heat exchanger through a pipeline to form a heat transfer oil circulation, the heat pipe heat exchanger is interconnected with the regulating water tank through a pipeline to form a primary water circulation, the regulating water tank is interconnected with the conversion valve through a pipeline to form a secondary water circulation, the regulating water tank is provided with a water replenishment port, and the conversion valve is connected with the heating user and the hot water equipment through a pipeline;

[0009] The heat transfer oil circulation is used to transfer the waste heat generated by the transformer to the evaporation section of the heat pipe heat exchanger through the heat transfer oil. The primary water circulation absorbs heat through the condensation section of the heat pipe heat exchanger and transports hot water to the regulating water tank, which is then connected to the secondary water circulation through the regulating water tank. The secondary water circulation transfers the heat to the heating users.

[0010] Furthermore, the transformer is used to generate waste heat during operation; the heat pipe heat exchanger is provided with one or more heat pipes, and the evaporation section and the condensation section are used for heat exchange with the high-temperature medium and the low-temperature medium respectively; the regulating water tank is used to stabilize the water volume and realize the connection between the primary water cycle and the secondary water cycle; the conversion valve is used to realize the switching between the heating mode in the heating season and the cold water preheating mode in the non-heating season.

[0011] Furthermore, the heat pipe heat exchanger is provided with an upper cavity and a lower cavity, the upper cavity and the lower cavity are separated by a partition, the partition is provided with a plurality of through holes, each through hole is fixedly connected to a heat pipe, the heat pipe is filled with refrigerant as a heat exchange medium, the upper cavity and the heat pipe located in the upper cavity form a condensation section, and the lower cavity and the heat pipe located in the lower cavity form an evaporation section; the phase change principle of the heat exchange medium absorbing heat and evaporating in the evaporation section and releasing heat and condensing in the condensation section is utilized to achieve efficient heat transfer.

[0012] Furthermore, the heat pipe is made of metal threaded pipe or micro-groove pipe, and the upper cavity, lower cavity, heat pipe and partition are brazed and connected by stainless steel plates to prevent oil leakage during heat exchange, and the outer surface of the heat pipe heat exchanger is provided with an insulation layer to reduce heat exchange loss; the condensing section and the evaporating section are respectively provided with an input port and an output port, the input port and the output port of the evaporating section are interconnected with the transformer through a pipeline, and the input port and the output port of the condensing section are interconnected with the regulating water tank through a pipeline. Furthermore, the water replenishment port of the regulating water tank is connected to the municipal water network, which is used to realize automatic water replenishment when the system changes from closed operation to open operation to ensure the stability of the water volume in the system.

[0013] Furthermore, the conversion valve is used to switch the heat consumption mode between the heating season and the non-heating season according to seasonal changes, so as to directly supply the hot water generated by the system to the building for radiant heating or to be used as domestic cold water preheating.

[0014] Furthermore, the system is also provided with a heat transfer oil pump, a primary water pump, a secondary water pump and a make-up water pump, so as to ensure the stable circulation operation of the fluid in each working cycle.

[0015] Furthermore, temperature sensors are provided at key nodes of the system to monitor the temperature of each node and provide a basis for system regulation. The key nodes include: the oil outlet of the thermal oil circulation, the oil return end of the thermal oil circulation, the water outlet of the primary water circulation, the water return end of the primary water circulation, the top and bottom of the regulating water tank, and the water supply and return ends of the heating users.

[0016] Furthermore, it also includes a control system, which jointly regulates the working status of the conversion valve and each pump based on the system operating status monitored by the temperature sensor, so as to realize the adaptive operation of the waste heat recovery system in different modes.

[0017] The present invention also provides a transformer waste heat recovery method based on heat pipe heat exchange, comprising the following steps:

[0018] (1) Utilize the waste heat generated by the transformer to transfer the heat to the evaporation section of the heat pipe heat exchanger through the circulation of thermal oil;

[0019] (2) In a heat pipe heat exchanger, the phase change effect of the refrigerant is used to transfer heat from the evaporation section to the condensation section, and then the heat is absorbed by the primary water cycle;

[0020] (3) The hot water in the primary water cycle is transported to the regulating water tank, where the water volume is regulated and stored, and the water is switched to the secondary water cycle through a conversion valve according to seasonal demand;

[0021] (4) Heat is transferred to heat users through secondary water circulation, realizing heat absorption in the heating season or cold water preheating in the non-heating season.

[0022] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0023] 1. The heat exchange efficiency is significantly improved by using the phase change heat transfer principle of the heat pipe heat exchanger. The heat pipe is filled with a low-boiling-point refrigerant, which absorbs heat in the evaporation section and releases heat in the condensation section. It can achieve fast and efficient heat energy transfer under medium and low temperature heat source conditions, thereby overcoming the problem of insufficient heat exchange efficiency of traditional heat exchangers under low temperature conditions. It can also simplify the complexity of the system, has a huge advantage in operating costs, and is more suitable for promotion in the transformation of the thermal management system of existing substations.

[0024] 2. The system adopts a hierarchical heat exchange structure of thermal oil circulation, primary water circulation and secondary water circulation to make full use of the waste heat generated by the transformer. The heat is quickly taken out by the thermal oil, transferred to the primary water through the heat pipe heat exchanger, and then the water volume is balanced in the regulating water tank. The heat energy is supplied to the heat user through the secondary water circulation, realizing the efficient utilization and transfer of heat energy, reducing the large amount of energy consumption and operating costs in the traditional air conditioning cooling mode.

[0025] 3. Equipped with a regulating water tank and a water inlet design, it can automatically replenish water when the system changes from closed to open operation, ensuring that the water volume of the heat exchange system is stable under different working conditions, thereby ensuring a continuous and stable heat exchange effect. In addition, the stratification phenomenon in the regulating water tank reduces the heat loss caused by the mixing of cold and hot water, further improving the overall thermal energy utilization rate of the system.

[0026] 4. By setting a conversion valve, the intelligent switching between the two heat consumption modes in the heating season and the non-heating season can be realized. This design can accurately match user heating and domestic cold water preheating according to seasonal waste heat temperature changes and heat user needs, which not only meets the actual needs of different heat users, but also avoids energy waste caused by temperature fluctuations, prolongs the effective use time of equipment throughout the year, and improves economic benefits. In addition, more heat consumption solutions can better meet the heat needs of different heat users near the substation, which can upgrade the substation to a new node for regional heat energy supply and expand a broader space for urban planning and construction.

[0027] 5. The system deploys temperature sensors at key nodes and combines the joint control of power equipment (such as various circulating pumps) to enable the system to monitor and adjust the operating status of each working cycle in real time. Such closed-loop control not only ensures that the transformer operates at a safe temperature, but also makes the waste heat recovery process more efficient and flexible, reducing the risk of system operation.

[0028] 6. The system uses the waste heat generated by the transformer as a thermal energy resource, replacing the traditional transformer air conditioning heat dissipation, saving the operation investment of refrigeration and air conditioning. The use of thermal energy resources shares part of the pressure of the heating system, while preventing the waste heat generated by the equipment from being directly discharged into the atmosphere, which has a certain contribution to reducing carbon dioxide emissions and alleviating the urban heat island effect.

[0029] In summary, the present invention achieves energy efficiency improvement in the entire process from transformer waste heat extraction to heat energy distribution by optimizing heat exchange structure, fine water volume management, intelligent mode switching and real-time monitoring and control, which not only saves energy and reduces operation and maintenance costs, but also reduces direct waste heat emissions, and has good environmental and economic benefits. In addition, the present invention can give full play to the utilization value of transformer waste heat in practical applications, solve the problems of low heat exchange efficiency, high energy consumption, and inaccurate system control in traditional technologies, and achieve the superior effects of high efficiency, stability, energy saving and environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure and principle of the transformer waste heat system based on heat pipe heat exchange of the present invention.

[0031] Figure 2 and Figure 3 They are respectively the top view and side view cross-sectional structural schematic diagrams of the heat pipe exchanger.

[0032] Attached figures: 1. Transformer; 2. Evaporation section; 3. Condensation section; 4. Heat pipe heat exchanger; 5. Regulating water tank; 6. Conversion valve; 7. Heating user; 8. Hot water equipment; 9. Water filling port; A. Thermal oil circulation; B. Primary water circulation; C. Secondary water circulation. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0034] In the description of the present invention, the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention rather than requiring the present invention to be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention. The terms "connected" and "connection" used in the present invention should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a direct connection or an indirect connection through an intermediate component; it can also be an electrical connection or signal transmission; for those of ordinary skill in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0035] See also Figure 1 The present embodiment provides a transformer waste heat system based on heat pipe heat exchange, which can provide a heating mode for heating users in the heating season, and can provide a cold water preheating mode for the hot water equipment of heating users in the non-heating season, including a transformer 1, a heat pipe heat exchanger 4, a regulating water tank 5, and a conversion valve 6; the heat pipe heat exchanger 4 includes an evaporation section 2 and a condensation section 3; in the present embodiment, the transformer 1 adopts an oil-immersed transformer.

[0036] The transformer 1 is interconnected with the heat pipe heat exchanger 4 through a pipeline to form a heat transfer oil circulation A, the heat pipe heat exchanger 4 is interconnected with the regulating water tank 5 through a pipeline to form a primary water circulation B, the regulating water tank 5 is interconnected with the conversion valve 6 through a pipeline to form a secondary water circulation C, the regulating water tank 5 is provided with a water replenishment port (9), and the conversion valve 6 is connected with the heating user 7 and the hot water equipment 8 through a pipeline;

[0037] Specifically, the heat transfer oil cycle A includes: a transformer 1 for generating heat, heat transfer oil for conducting heat from the transformer 1, and an evaporation section 2 of a heat pipe heat exchanger 4 for exchanging heat with the high-temperature heat transfer oil;

[0038] The primary water cycle B includes: primary water for extracting heat from the heat transfer oil, a condensing section 3 of a heat pipe heat exchanger for heat exchange with low-temperature cold water, and a regulating water tank 5 for stabilizing the system and connecting to the secondary water cycle;

[0039] The secondary water cycle C includes: secondary water for conducting heat to the heating user 7, and a conversion valve 6 for switching the heat consumption mode.

[0040] For details, see Figure 2 and Figure 3 In the heat pipe heat exchanger 4, a number of heat pipes are arranged vertically. According to the length of the evaporation section and the condensation section of the heat pipe, the interior of the heat pipe heat exchanger is made into two cavities, which are called the evaporation section 2 and the condensation section 3 respectively. The low-temperature heat transfer oil absorbs heat through the transformer 1 and the temperature rises to become high-temperature heat transfer oil. The high-temperature heat transfer oil exchanges heat with the liquid working medium in the heat pipe through the evaporation section 2. The liquid working medium absorbs heat and the temperature rises, and then changes phase to become gaseous. Due to the concentration difference, the gaseous working medium diffuses from the evaporation section 2 to the condensation section 3. After heat exchange with the liquid working medium, the temperature of the high-temperature heat transfer oil drops and flows back to the transformer 1, completing the heat transfer oil cycle A.

[0041] When the low-temperature primary water flows through the condensation section 3, it exchanges heat with the high-temperature gaseous working medium, and the temperature of the gaseous working medium decreases and changes phase to liquid. Due to gravity, the liquid working medium flows back to the evaporation section 2 from the condensation section 3. After heat exchange with the gaseous working medium, the temperature of the primary water increases and flows into the upper inlet of the regulating water tank, and enters the secondary water cycle C from the upper outlet of the regulating water tank. Due to the density difference caused by the temperature difference, the water in the regulating water tank will be stratified, and the low-temperature water will flow back to the condensation section 3 through the lower outlet to continue heat exchange, completing the primary water cycle B.

[0042] When the high-temperature primary water flows into the conversion valve 6 through the upper outlet of the regulating water tank, the heating mode is selected in the heating season, and the high-temperature hot water directly flows into the heating pipeline in the building, and the low-temperature return water flows into the lower inlet of the regulating water tank 5 through the conversion valve 6. In the non-heating season, the non-heating season cold water preheating mode is selected. At this time, the regulating water tank 5 opens the water replenishment port 9, and the high-temperature hot water directly flows into the hot water equipment in the building for secondary heating and then enters the building hot water supply system, completing the secondary water cycle C.

[0043] Preferably, in order to ensure that the transformer can operate at a safe temperature and the waste heat recovery system can operate efficiently, the temperatures of important nodes of the system can be monitored, such as the high-temperature thermal oil outlet temperature, the low-temperature thermal oil return temperature, the primary water outlet temperature, the primary water return temperature, the water temperature at the top and bottom of the regulating water tank, the heat user supply temperature, the heat user return temperature, etc.

[0044] Preferably, the system scale will change accordingly for transformers with different workloads. When the system reaches a certain level, the system needs to be equipped with power equipment such as a thermal oil pump, a primary water pump, a secondary water pump, and a make-up water pump to ensure that each heat exchange cycle can operate stably and efficiently.

[0045] Preferably, the operating status of the system can be monitored by a temperature sensor, and valves need to be set at important nodes to adjust the system in conjunction with a variable frequency power device according to the system operating conditions. In addition, the setting of valves is also to provide convenient conditions for system installation, regular maintenance, and replacement.

[0046] Preferably, the water in the regulating water tank will be stratified due to the density difference caused by the temperature difference, which reduces the heat loss caused by the mixing of cold and hot water. Therefore, a device such as a diverter baffle can be set in the regulating water tank to further promote this stratification and reduce heat loss.

[0047] Preferably, the mode conversion in the system is mainly achieved through the conversion valve. The mode switching is also the switching of the heating user. When switching, it is necessary to systematically adjust the control valves in each cycle to achieve the re-matching of the entire system to the heating user when the mode is switched.

[0048] Preferably, by long-term recording of system operating parameters in different modes, a numerical simulation of the waste heat system can be established by means of numerical simulation. The numerical model can be used to improve the joint regulation of the conversion valve and the loop valve with the power device.

[0049] Preferably, this embodiment also provides a transformer waste heat recovery method based on heat pipe heat exchange, comprising the following steps:

[0050] (1) Utilizing the waste heat generated by the transformer, the heat is transferred to the evaporation section of the heat pipe heat exchanger through the heat transfer oil circulation, forming a heat transfer oil circulation A;

[0051] (2) In a heat pipe heat exchanger, the phase change effect of the refrigerant is used to transfer heat from the evaporation section to the condensation section, and then the heat is absorbed by the primary water cycle;

[0052] (3) The hot water in the primary water cycle is transported to the regulating water tank, where the water volume is regulated and stored, and the water is switched to the secondary water cycle through a conversion valve according to seasonal demand;

[0053] (4) Heat is transferred to heat users through secondary water circulation, realizing heat absorption in the heating season or cold water preheating in the non-heating season.

[0054] In addition, a hot oil circulation pump is set in the heat transfer oil circulation loop A, a primary water circulation pump is set in the primary water circulation loop B, a water replenishment pump is set at the water replenishment port 9 of the regulating water tank 5, and a hot water circulation pump and a water supply pump are set at the heat user connection.

[0055] Temperature sensors are set at the nodes to monitor the high-temperature thermal oil outlet temperature, low-temperature thermal oil return temperature, primary water outlet temperature, primary water return temperature, water temperature at the top and bottom of the regulating water tank, heat user water supply temperature, and heat user return temperature.

[0056] The joint control mechanism of the conversion valve and the power unit is improved by establishing a numerical model.

[0057] In this embodiment, the working steps of the transformer waste heat recovery system based on heat pipe heat exchange include:

[0058] 1. Transformer thermal oil cooling:

[0059] When the transformer is working, part of the electric energy is dissipated as heat energy. The heat accumulation makes the surface temperature of the equipment rise. At this time, the low-temperature heat transfer oil flows in to exchange heat with the equipment. After the heat exchange, the low-temperature heat transfer oil heats up and the surface temperature of the equipment cools down. The heated heat transfer oil enters the evaporation end of the heat pipe heat exchanger for heat exchange, and then flows back to the transformer for heat exchange. The heat is transferred from the transformer.

[0060] 2. Heat transfer by heat pipe:

[0061] The high-temperature heat transfer oil exchanges heat with the liquid working medium in the heat pipe through the evaporation end. The liquid working medium absorbs heat, its temperature rises, and changes phase to gas. When the low-temperature primary water flows through the condensation section 3, it exchanges heat with the high-temperature gaseous working medium. The gaseous working medium temperature decreases and changes phase to liquid. Through the phase change of the working medium in the heat pipe, the heat is transferred from the heat transfer oil to the primary water.

[0062] 3. Heating in different modes:

[0063] The primary water flows out from the top outlet of the regulating water tank and enters the secondary water circulation. The hot water flows to the conversion valve and enters different heat users according to different heat consumption schemes. When switching between different modes, the conversion valve and the loop valve are jointly regulated with the power device to achieve the normal operation of the system.

[0064] The present invention can be applied to the energy-saving transformation of existing transformer substations and the energy-saving design of new transformer substations, can reduce the pollution of waste heat emission to the environment, provide economic benefits for transformer substations, and broaden the functions of transformer substations in municipal planning.

[0065] The above-mentioned voltage transformer, heat pipe heat exchanger, regulating water tank, conversion valve, temperature sensor, regulating valve, and variable frequency pump can adopt devices and materials in the existing technology; or adopt devices and materials in the existing technology and adopt conventional technical means to construct.

[0066] The present invention is not limited to the embodiments described above. The above description of the specific embodiments is intended to describe and illustrate the technical solution of the present invention. The above specific embodiments are merely illustrative and not restrictive. Without departing from the scope of the present invention and the scope of protection of the claims, a person of ordinary skill in the art can also make many forms of specific changes under the guidance of the present invention, which all fall within the scope of protection of the present invention.

Claims

1. A transformer waste heat recovery system based on heat pipe heat exchange, characterized in that: Used to realize two waste heat consumption modes: heating in the heating season and cold water preheating in the non-heating season; comprising a transformer (1), a heat pipe heat exchanger (4), a regulating water storage tank (5), and a conversion valve (6); the heat pipe heat exchanger (4) comprises an evaporation section (2) and a condensation section (3); The transformer (1) is interconnected with the heat pipe heat exchanger (4) through a pipeline to form a heat transfer oil circulation (A), the heat pipe heat exchanger (4) is interconnected with the regulating water tank (5) through a pipeline to form a primary water circulation (B), the regulating water tank (5) is interconnected with the conversion valve (6) through a pipeline to form a secondary water circulation (C), the regulating water tank (5) is provided with a water replenishment port (9), and the conversion valve (6) is connected with the heating user (7) and the hot water equipment (8) through a pipeline; The heat transfer oil cycle is used to transfer the waste heat generated by the transformer to the evaporation section of the heat pipe heat exchanger (4) through the heat transfer oil, and the primary water cycle (B) absorbs heat through the condensation section (3) of the heat pipe heat exchanger (4), and transports hot water to the regulating water storage tank (5), and then connects to the secondary water cycle (C) through the regulating water storage tank (5), and the secondary water cycle (C) transfers the heat to the heating user.

2. According to claim 1, a transformer waste heat recovery system based on heat pipe heat exchange is characterized in that: The transformer is used to generate waste heat during operation; one or more heat pipes are arranged inside the heat pipe heat exchanger, and the evaporation section (2) and the condensation section (3) are used to exchange heat with the high-temperature medium and the low-temperature medium respectively; the regulating water tank (5) is used to stabilize the water volume and realize the connection between the primary water cycle (B) and the secondary water cycle (C); the conversion valve is used to realize the switching between the heating mode in the heating season and the cold water preheating mode in the non-heating season.

3. According to claim 1, a transformer waste heat recovery system based on heat pipe heat exchange is characterized in that: The heat pipe heat exchanger is provided with an upper cavity and a lower cavity, the upper cavity and the lower cavity are separated by a partition, the partition is provided with a plurality of through holes, each through hole is fixedly connected to a heat pipe, the heat pipe is filled with a refrigerant as a heat exchange medium, the upper cavity and the heat pipe located in the upper cavity form a condensation section (3), and the lower cavity and the heat pipe located in the lower cavity form an evaporation section (2); the phase change principle of the heat exchange medium absorbing heat and evaporating in the evaporation section (2) and releasing heat and condensing in the condensation section (3) is utilized to achieve efficient heat transfer.

4. A transformer waste heat recovery system based on heat pipe heat exchange according to claim 1 or 3, characterized in that: The heat pipe is a metal threaded pipe or a micro-groove pipe, and the upper cavity, the lower cavity, the heat pipe and the partition are brazed and connected with stainless steel plates to prevent oil leakage during the heat exchange process, and the outer surface of the heat pipe heat exchanger is provided with an insulation layer to reduce heat exchange losses; the condensation section (3) and the evaporation section (2) are respectively provided with an input port and an output port, the input port and the output port of the evaporation section (2) are interconnected with the transformer (1) through a pipeline, and the input port and the output port of the condensation section (3) are interconnected with the regulating water tank (5) through a pipeline.

5. The transformer waste heat recovery system based on heat pipe heat exchange according to claim 1 is characterized in that: The water replenishment port of the regulating water tank is connected to the municipal water network, and is used to realize automatic water replenishment when the system changes from closed operation to open operation, so as to ensure the stability of the water volume in the system.

6. The transformer waste heat recovery system based on heat pipe heat exchange according to claim 1, characterized in that: The conversion valve (6) is used to switch the heat consumption mode between the heating season and the non-heating season according to seasonal changes, so as to respectively realize that the hot water generated by the system is directly supplied to the building for radiant heating or used as domestic cold water preheating.

7. The transformer waste heat recovery system based on heat pipe heat exchange according to claim 1 is characterized in that: The system is also provided with a heat transfer oil pump, a primary water pump, a secondary water pump and a water replenishment pump, which are used to ensure the stable circulation operation of the fluid in each working cycle.

8. The transformer waste heat recovery system based on heat pipe heat exchange according to claim 1, characterized in that: Temperature sensors are installed at key nodes of the system to monitor the temperature of each node and provide a basis for system regulation. The key nodes include: the oil outlet of thermal oil circulation (A), the oil return of thermal oil circulation (A), the water outlet of primary water circulation (B), the return of primary water circulation (B), the top and bottom of the regulating water tank, and the water supply and return ends of heating users.

9. The transformer waste heat recovery system based on heat pipe heat exchange according to claim 8, characterized in that: It also includes a control system, which jointly regulates the working states of the conversion valve (6) and each pump based on the system operating state monitored by the temperature sensor, so as to realize adaptive operation of the waste heat recovery system in different modes.

10. A method for recovering waste heat from a transformer based on heat pipe heat exchange, characterized in that: The following steps are involved: (1) Utilize the waste heat generated by the transformer to transfer the heat to the evaporation section of the heat pipe heat exchanger through the circulation of thermal oil; (2) In a heat pipe heat exchanger, the phase change effect of the refrigerant is used to transfer heat from the evaporation section to the condensation section, and then the heat is absorbed by the primary water cycle; (3) The hot water in the primary water cycle is transported to the regulating water tank, where the water volume is regulated and stored, and the water is switched to the secondary water cycle through a conversion valve according to seasonal demand; (4) Heat is transferred to heat users through secondary water circulation, realizing heat absorption in the heating season or cold water preheating in the non-heating season.

Images