Box transformer heat dissipation system and method based on coupling of phase change heat storage and forced convection

Abstract

The application discloses a box transformer heat dissipation system based on phase change heat storage and forced convection coupling and a method thereof, which comprises a box transformer shell and a transformer body installed in the box transformer shell. The inside of the box transformer shell is provided with uniformly distributed forced convection structures and inert gas circulation heat conduction structures. The outside of the transformer body is provided with uniformly distributed phase change heat storage structures. The system is based on forced convection structures, and the power of a fan is intelligently adjusted to ensure normal heat dissipation and realize low-power energy-saving operation. When facing instantaneous heat shock, the phase change heat storage structures can quickly absorb and store a large amount of latent heat, effectively suppress temperature spikes, and gain buffer time for system response. If the heat load is continuous, the inert gas circulation heat conduction structures are started immediately, inert gas circulation and semiconductor refrigeration are utilized for deep active cooling, the heat storage capacity of the phase change material is efficiently recovered, and the risk of oxidation and corrosion is avoided.

Description

Technical Field

[0001] This invention relates to the field of transformer heat dissipation system technology, and more specifically, to a transformer substation heat dissipation system and method based on phase change heat storage and forced convection coupling. Background Technology

[0002] As a critical node in the power system for energy conversion and distribution, the long-term stable operation of the transformer—the core equipment inside the prefabricated substation—is crucial to the reliability of the entire power supply network. During operation, the transformer generates continuous heat due to iron and copper losses, and this temperature rise directly affects the aging rate of the insulation materials and the lifespan of the equipment. Especially under complex operating conditions such as high temperatures in summer, short-term overloads, and poor ventilation, heat can easily accumulate inside the prefabricated substation, forming hot spots. If heat dissipation is not timely, it will lead to accelerated deterioration of insulation performance, causing malfunctions or even burn-out accidents, resulting in significant economic losses and social impact.

[0003] Currently, the mainstream heat dissipation solution for transformer substations mainly relies on forced air cooling. This solution typically involves creating ventilation holes in the enclosure and installing axial flow fans to remove heat through air convection. However, this traditional solution has significant limitations: First, its heat dissipation capacity passively depends on the ambient temperature, and its efficiency drops sharply when the ambient temperature in summer is close to or exceeds the allowable temperature rise inside the enclosure. Second, the fans usually operate at a fixed power or within a simple temperature control range, resulting in a slow response and difficulty in coping with sudden and drastic fluctuations in transformer load, easily leading to frequent fan start-stop cycles, which affects equipment lifespan and increases energy consumption. Furthermore, simple air convection cannot solve the problem of "hot spots" caused by localized overheating of the transformer, and uneven heat distribution still threatens equipment safety.

[0004] To overcome the shortcomings of forced air cooling, some improvement schemes have introduced phase change thermal storage materials. These materials can absorb or release a large amount of latent heat at the phase change temperature point, theoretically buffering instantaneous temperature rises. However, existing applications often simply fill or attach phase change materials to the surface of the heating element, resulting in the following drawbacks: First, phase change materials generally have low thermal conductivity and slow thermal response speed. While absorbing heat, their own temperature rise is also slow, exhibiting a "thermal hysteresis" phenomenon, which cannot suppress temperature spikes in time; Second, under continuous high loads, the phase change material's thermal storage capacity becomes saturated after complete melting. If there is no effective subsequent cooling method to allow it to solidify and recover, it will completely fail, and the system will revert to a single air cooling mode, with the heat dissipation bottleneck still present; Third, phase change materials are prone to oxidation and leakage when in a high-temperature molten state for extended periods, posing stability and safety hazards.

[0005] In addition, some studies have attempted to use active cooling solutions such as liquid cooling or direct cooling by thermoelectric coolers. However, liquid cooling systems have complex piping, are prone to leakage, freezing, and corrosion, require high maintenance, and have difficulty guaranteeing reliability in the harsh environment of outdoor transformer substations. On the other hand, if thermoelectric coolers directly cool large heat-generating components, energy consumption is extremely high, and improper handling of the temperature difference between the hot and cold ends can easily lead to condensation, causing new electrical safety problems.

[0006] In summary, existing transformer substation cooling technologies suffer from problems such as insufficient heat dissipation capacity, slow response, high energy consumption, and inability to balance hotspots, as well as drawbacks such as system complexity, poor reliability, and difficult maintenance. Therefore, those skilled in the art have provided a transformer substation cooling system and method based on phase change thermal storage and forced convection coupling to solve the aforementioned problems. Summary of the Invention

[0007] The purpose of this invention is to provide a prefabricated substation heat dissipation system and method based on phase change thermal storage and forced convection coupling, which solves the technical problems of insufficient heat dissipation capacity, slow response, local hot spots, easy failure of phase change thermal storage materials, and poor system reliability of prefabricated substation heat dissipation systems under complex operating conditions.

[0008] To solve the above problems, the present invention adopts the following technical solution;

[0009] A transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling includes a transformer substation housing and a transformer body installed inside it. The interior of the transformer substation housing is provided with a uniformly distributed forced convection structure and an inert gas circulating heat conduction structure. The exterior of the transformer body is provided with a uniformly distributed phase change thermal storage structure. The inert gas circulating heat conduction structure is used in conjunction with the phase change thermal storage structure.

[0010] The forced convection structure includes a top air trough and a bottom air trough. The top air trough and the bottom air trough are respectively opened at the top and bottom of the transformer substation housing and are both connected to the interior of the transformer substation housing. The top air trough is located on the vertical line at the top of the bottom air trough. An exhaust axial flow fan is installed on the inner wall of the top air trough, and an intake axial flow fan is fixedly installed on the inner wall of the bottom air trough.

[0011] The phase change thermal storage structure includes a heat insulation box, which is detachably connected to the transformer body by bolts. A heat-conducting plate is encapsulated at the opening of the heat insulation box close to the transformer body. The interior of the heat insulation box is isolated into a sealed space by the heat-conducting plate. The heat-conducting plate is in contact with the heat-generating position of the transformer body. The interior of the heat insulation box is filled with a phase change thermal storage material layer, which is a paraffin organic PCM that has been thermally enhanced and flame-retardant modified.

[0012] The inert gas circulating heat conduction structure includes a circulating refrigeration box, which is fixedly installed on the inner top wall of the transformer substation housing. The circulating refrigeration box has a refrigeration chamber inside, and a semiconductor refrigeration chip is fixedly installed on the inner wall of the refrigeration chamber. The heat dissipation end of the semiconductor refrigeration chip extends through and to the top of the transformer substation housing. Uniformly distributed airflow baffles are connected to the inner wall of the refrigeration chamber. Adjacent airflow baffles are staggered to form airflow channels, extending the contact time between the airflow and the semiconductor refrigeration chip. The inner wall of the circulating refrigeration box is fixedly... A circulating pump connected to the interior of the refrigeration chamber is fixedly installed. A bent heat-conducting pipe is installed inside the heat insulation box. The bent heat-conducting pipe is continuously bent and in contact with the phase change heat storage material layer. Both ends of the bent heat-conducting pipe pass through and extend to the top of the heat insulation box. A supply pipe is connected to the circulating pump. A return pipe is connected to the inner wall of the refrigeration chamber. The bottom ends of the supply pipe and the return pipe are respectively connected to the two ends of the bent heat-conducting pipe. The refrigeration chamber, the circulating pump, the supply pipe, the bent heat-conducting pipe and the return pipe constitute a circulation system and are filled with nitrogen.

[0013] The transformer housing integrates a processor and a signal transmission module. The signal transmission module is used to realize the signal connection and transmission between the backend and the processor. The transformer housing also integrates uniformly distributed temperature sensors. The temperature sensors are used to acquire the temperature values ​​of each installation position inside the transformer housing and transmit them to the processor. The processor controls the start-up and shutdown and power of the intake axial flow fan and the exhaust axial flow fan by comparing the acquired temperature sensor values ​​with the threshold set by the backend.

[0014] A status sensor is installed on the inner wall of the heat insulation box. The status sensor is used to acquire the status signal of the phase change thermal storage material layer and transmit it to the processor. The processor controls the opening and closing and power of the circulation pump and the semiconductor cooling chip by comparing the acquired status signal with the threshold set in the background.

[0015] Compared with the prior art, the advantages of this invention are:

[0016] The present invention provides a highly integrated, intelligent, collaborative, and robust active thermal management solution. Its core advantage lies in achieving precise, efficient, and adaptive control of the internal temperature field of the transformer substation through multi-level and multi-mode heat dissipation mechanism coupling.

[0017] The system is based on a forced convection structure and achieves low-power energy-saving operation while ensuring normal heat dissipation through intelligent adjustment of fan power. When faced with instantaneous thermal shock, the phase change thermal storage structure can quickly absorb and store a large amount of latent heat, effectively suppressing temperature peaks and providing buffer time for system response. If the heat load continues, the inert gas circulation heat conduction structure is activated, using inert gas circulation and semiconductor refrigeration for deep active cooling, efficiently restoring the thermal storage capacity of the phase change material, and avoiding the risks of oxidation and corrosion.

[0018] Under extreme operating conditions, the airflow guiding structure can dynamically optimize the air duct, guide the airflow to directly enhance the scouring of key heat dissipation parts, and form a dual heat dissipation channel with the internal circulation cooling, completely eliminating hot spots.

[0019] In addition, the system achieves real-time monitoring, intelligent threshold judgment and remote operation and maintenance through a sensor network and intelligent processors distributed throughout the system. It is also equipped with an electric heating plate pre-start strategy to eliminate thermal hysteresis and a modular and detachable design to reduce maintenance complexity. Ultimately, the system significantly improves the reliability, adaptability and full life cycle economy of the equipment in the face of complex working conditions while ensuring that the transformer always operates within a safe temperature range. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural diagram of the transformer substation housing of the present invention;

[0021] Figure 2 This is a frontal cross-sectional view of the present invention.

[0022] Figure 3 This is a schematic diagram of the cross-sectional structure of the top air groove of the present invention;

[0023] Figure 4 This is a schematic cross-sectional view of the inert gas circulating heat conduction structure and phase change heat storage structure of the present invention.

[0024] Figure 5 This is a schematic diagram of the exploded three-dimensional structure of the phase change thermal storage material layer of the present invention;

[0025] Figure 6 This is a schematic diagram of the airflow guiding structure of the present invention;

[0026] Figure 7 This is a schematic diagram illustrating the principle of the present invention;

[0027] Figure 8 This is a schematic diagram of the steps of the present invention.

[0028] Explanation of the labels in the diagram:

[0029] 1. Transformer enclosure; 2. Transformer body; 3. Forced convection structure; 301. Top air duct; 302. Bottom air duct; 303. Exhaust axial flow fan; 304. Intake axial flow fan; 4. Inert gas circulation heat conduction structure; 401. Circulating refrigeration box; 402. Refrigeration chamber; 403. Semiconductor refrigeration chip; 404. Airflow baffle; 405. Circulating pump; 406. Bent heat conduction pipe; 407. Supply pipe; 408. Return pipe; 5. Phase change 501. Thermal storage structure; 502. Insulation box; 503. Heat conduction plate; 504. Phase change thermal storage material layer; 6. Processor; 7. Signal transmission module; 8. Temperature sensor; 9. Status sensor; 10. Electric heating plate; 11. Dustproof net; 12. Heat dissipation fins; 13. Airflow guiding structure; 1301. Small electric push rod; 1302. Synchronous shaft; 1303. Air guide plate; 1304. Synchronous gear; 1305. Gear plate; 14. Pressure sensor. Detailed Implementation

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0031] Example 1:

[0032] Please see Figures 1-8 In this invention, a transformer substation heat dissipation system based on phase change heat storage and forced convection coupling includes a transformer substation housing 1 and a transformer body 2 installed inside it. The transformer substation housing 1 is provided with a uniformly distributed forced convection structure 3 and an inert gas circulation heat conduction structure 4. The forced convection structure 3 includes a top air groove 301 and a bottom air groove 302. The top air groove 301 and the bottom air groove 302 are respectively opened at the top and bottom of the transformer substation housing 1 and are both connected to the interior of the transformer substation housing 1. The top air groove 301 is located on the vertical line of the top of the bottom air groove 302. An exhaust axial flow fan 303 is installed on the inner wall of the top air groove 301, and an intake axial flow fan 304 is fixedly installed on the inner wall of the bottom air groove 302.

[0033] The inert gas circulating heat conduction structure 4 includes a circulating refrigeration box 401, which is fixedly installed on the inner top wall of the transformer housing 1. A refrigeration chamber 402 is formed inside the circulating refrigeration box 401. A semiconductor cooling chip 403 is fixedly installed on the inner wall of the refrigeration chamber 402. The heat dissipation end of the semiconductor cooling chip 403 extends through and to the top of the transformer housing 1. Uniformly distributed airflow baffles 404 are connected to the inner wall of the refrigeration chamber 402. Adjacent airflow baffles 404 are staggered to form airflow channels, extending the contact time between the airflow and the semiconductor cooling chip 403. A connection between the circulating refrigeration box 401 and the refrigeration chamber 402 is fixedly installed on the inner wall of the circulating refrigeration box 401. The internally connected circulation pump 405 and the heat insulation box 501 are equipped with a bent heat conduction pipe 406. The bent heat conduction pipe 406 is in a continuous bent state and is in contact with the phase change heat storage material layer 503. Both ends of the bent heat conduction pipe 406 pass through and extend to the top of the heat insulation box 501. The circulation pump 405 is connected to a supply pipe 407. The inner wall of the refrigeration chamber 402 is connected to a return pipe 408. The bottom ends of the supply pipe 407 and the return pipe 408 are respectively connected to the two ends of the bent heat conduction pipe 406. The refrigeration chamber 402, the circulation pump 405, the supply pipe 407, the bent heat conduction pipe 406 and the return pipe 408 constitute a circulation system and are filled with nitrogen.

[0034] A uniformly distributed phase change heat storage structure 5 is provided on the outer side of the transformer body 2. An inert gas circulating heat conduction structure 4 is used in conjunction with the phase change heat storage structure 5. The phase change heat storage structure 5 includes a heat insulation box 501. The heat insulation box 501 is detachably connected to the transformer body 2 by bolts. A heat conduction plate 502 is encapsulated at the opening of the heat insulation box 501 close to the transformer body 2. The interior of the heat insulation box 501 is isolated into a sealed space by the heat conduction plate 502. The heat conduction plate 502 is in contact with the heat-generating position of the transformer body 2. The interior of the heat insulation box 501 is filled with a phase change heat storage material layer 503. The phase change heat storage material layer 503 is a paraffin organic PCM, which has been thermally enhanced and flame-retardant modified.

[0035] The transformer housing 1 integrates a processor 6 and a signal transmission module 7. The signal transmission module 7 is used to realize the signal connection and transmission between the backend and the processor 6. The transformer housing 1 also integrates uniformly distributed temperature sensors 8. The temperature sensors 8 are used to acquire the temperature values ​​of each installation position inside the transformer housing 1 and transmit them to the processor 6. The processor 6 controls the opening and closing and power of the intake axial flow fan 304 and the exhaust axial flow fan 303 by comparing the threshold set by the backend with the acquired temperature sensor values.

[0036] A status sensor 9 is installed on the inner wall of the heat insulation box 501. The status sensor 9 is used to acquire the status signal of the phase change thermal storage material layer 503 and transmit it to the processor 6. The processor 6 controls the opening and closing and power of the circulation pump 405 and the semiconductor cooling chip 403 by comparing the acquired status signal with the threshold set in the background. The side of the heat insulation box 501 away from the transformer body 2 is connected to a uniformly distributed heat dissipation fin 12. The ends of the heat dissipation fin 12 are in contact with the phase change thermal storage material layer 503 inside the heat insulation box 501.

[0037] Both the supply pipe 407 and the return pipe 408 are flexible hoses made of heat-insulating material, and are detachably connected to the top of the bottom bent heat-conducting pipe 406 via a threaded sleeve.

[0038] A pressure sensor 14 is fixedly installed on the inner wall of the cooling chamber 402. The pressure sensor 14 is connected to the processor 6. The pressure sensor 14 is used to obtain the pressure value of nitrogen in the circulation system of the cooling chamber 402 and transmit it to the processor 6. The processor 6 compares the obtained pressure value with the background threshold and transmits it to the background.

[0039] In this invention, after the system is powered on for the first time, it automatically completes the self-test process of all components. All temperature sensors 8, status sensors 9, and air pressure sensors 14 complete signal calibration in sequence. The background sends pre-set operating parameters such as the fan start / stop threshold, the phase change material phase change state determination threshold, and the nitrogen circulation system air pressure alarm threshold to the processor 6 through the signal transmission module 7. At the same time, the dustproof nets 11 on the top and bottom of the transformer housing 1 cover the air inlet and outlet throughout the process to prevent external sand and insects from entering the transformer housing 1 and accumulating inside, causing electrical short circuit faults. The entire system enters the real-time monitoring standby state.

[0040] Under normal low-load conditions, temperature sensors 8, evenly distributed throughout the transformer housing 1, collect temperature values ​​from all areas inside the housing in real time and upload them to the processor 6 for comparison. When the temperature inside the housing is within the normal operating range, the processor 6 controls the intake axial flow fan 304 at the bottom air slot 302 to start drawing in low-temperature outside air, while the exhaust axial flow fan 303 at the top air slot 301 starts simultaneously to exhaust hot air from inside the housing, forming a vertical forced convection air duct with bottom inlet and top outlet. At the same time, the processor 6 dynamically adjusts the operating power of the two axial flow fans according to the real-time monitored temperature inside the housing. Under low load, the fan speed is reduced to achieve low-power energy-saving operation. Only when the temperature approaches the first-level temperature control threshold will the fan be increased to full power operation, ensuring heat dissipation while minimizing system operating energy consumption.

[0041] When the transformer body 2 experiences short-term overload or extreme ambient temperature rises in summer, the temperature of the local heating area of ​​the transformer body 2 rises rapidly. The high thermal conductivity heat conduction plate 502 installed in close contact with the heating surface will immediately transfer the heat to the phase change heat storage material layer 503 inside the insulation box 501. The paraffin organic PCM, which has been thermally enhanced and flame-retardant modified, will quickly absorb a large amount of latent heat at the phase change temperature point and transform from a solid to a liquid state. Within a few seconds, it will quickly reduce the sudden temperature rise of the local area of ​​the transformer body 2 and prevent the instantaneous temperature surge from triggering the high-frequency start-stop of the fan.

[0042] Meanwhile, as the overall temperature inside the transformer housing 1 gradually decreases, the phase change thermal storage material layer 503, which has absorbed a large amount of heat, will gradually dissipate heat to the air flowing inside the housing through the high thermal conductivity heat dissipation fins 12 on the outside. After completely releasing the latent heat, it will solidify back from a liquid state to a solid state, automatically restoring its thermal storage capacity. The entire phase change thermal storage and release process can be recycled and reused without additional maintenance. At the same time, the semi-enclosed heat insulation box 501 can prevent the heat of the phase change thermal storage material layer 503 from diffusing back to other non-heating areas, ensuring accurate heat output.

[0043] When the status sensor 9 continuously collects signals indicating that the phase change thermal storage material layer 503 remains in a molten state for a long time and cannot solidify on its own, and at the same time the temperature sensor 8 uploads the overall temperature inside the chamber, which continues to rise and exceeds the secondary temperature control threshold set in the background, the processor 6 automatically triggers the inert gas circulation heat conduction structure 4 to start.

[0044] When the semiconductor refrigeration chip 403 is powered on, its top heat dissipation end directly discharges the generated waste heat to the outside of the transformer housing 1. Its cold end, located inside the refrigeration chamber 402, is in full contact with the extended airflow channel arranged along the staggered airflow baffle 404. After the circulating nitrogen in the channel fully exchanges heat with the cold end of the semiconductor refrigeration chip 403, it is driven by the circulation pump 405 and transported through the heat-insulating material supply pipe 407 to the continuous bent heat conduction pipe 406 inside each phase change heat storage structure 5. It flows evenly through the entire phase change heat storage material layer 503 and quickly removes the large amount of latent heat accumulated, allowing the phase change material to cool down and solidify quickly to restore its full heat storage capacity. The entire circulation pipeline uses high-purity nitrogen as the heat exchange medium, so there is no risk of water vapor condensation or pipeline corrosion.

[0045] Meanwhile, the inertness property can also prevent the phase change thermal storage material layer 503 from oxidizing and failing due to long-term high-temperature contact with air. At the same time, the pressure sensor 14 installed inside the cooling chamber 402 monitors the internal pressure value of the entire circulation system in real time. Once a micro-leak in the pipeline causes the pressure to fall below the alarm threshold set in the background, the processor 6 will immediately push the fault alarm information to the remote operation and maintenance background through the signal transmission module 7, reminding the operation and maintenance personnel to complete the nitrogen pressure replenishment maintenance in time to avoid failure of the circulation heat dissipation function.

[0046] Throughout the entire operating cycle, the system will synchronously upload temperature data, phase change material status data, nitrogen circulation system pressure data, and operating status of each actuator to the remote operation and maintenance backend in real time via signal transmission module 7. This allows maintenance personnel to remotely adjust operating thresholds and retrieve historical operating data even when the system is unattended. Meanwhile, the supply pipe 407 and return pipe 408 adopt a detachable quick-connect structure with insulated flexible hoses and threaded sleeves. Through the multi-layered coupled operating logic of phase change heat storage peak shaving and buffering, forced convection normal heat dissipation, and inert gas circulation deep cooling, the entire system can achieve low-power energy-saving operation under normal operating conditions, and can also easily cope with various complex operating conditions such as extreme high temperature, short-term overload, and low temperature start-up, significantly extending the overall service life and power supply reliability of the transformer.

[0047] Please see Figures 1-3 The transformer housing 1 has a dustproof net 11 that can be detachably connected to both the top and bottom. The dustproof net 11 on the top shields and protects the top air slot 301 and the semiconductor cooling chip 403, while the dustproof net 11 on the bottom shields the bottom air slot 302.

[0048] In this invention, the dustproof nets 11 at the top and bottom of the transformer housing 1 are also designed to be detachable, so that maintenance personnel can quickly replace the dustproof nets 11 and perform cleaning and maintenance work, which greatly reduces the maintenance workload throughout the entire life cycle.

[0049] Example 2:

[0050] Please see Figure 4 , 5 7, wherein: an electric heating plate 10 is fixedly installed on the inner bottom wall of the heat insulation box 501, the electric heating plate 10 is in contact with the phase change heat storage material layer 503 at the bottom, the electric heating plate 10 is signal connected to the processor 6 and linked with the status sensor 9.

[0051] In this invention, when the system is started in a low-temperature winter environment or when the remote backend predicts that the power grid will experience a short-term peak overload, the status sensor 9 detects that all phase change thermal storage material layers 503 are completely in a solid state. The processor 6 will automatically link and control the electric heating plate 10 installed at the bottom of the corresponding insulation box 501 to start at low power for a short time, preheating and melting some of the paraffin phase change material in the bottom area, reserving enough latent heat storage space in advance. If the transformer body 2 experiences a sudden heating condition, the phase change thermal storage material layer 503 can immediately start the large latent heat absorption process, completely avoiding the thermal lag problem of the completely solid phase change material heating and absorbing heat, further improving the response speed of the whole system to short-term sudden thermal shock, and ensuring that the operating temperature of the transformer body 2 is always stable within the safe range given by the manufacturer.

[0052] Example 3:

[0053] Please see Figure 2 , 6 7, wherein: the interior of the transformer housing 1 is provided with a uniformly distributed airflow guiding structure 13, the airflow guiding structure 13 includes a small electric push rod 1301, the small electric push rod 1301 is installed on the inner wall of the transformer housing 1, the inner wall of the transformer housing 1 is rotatably connected with a synchronous shaft 1302 arranged at equal distances, a guide plate 1303 is fixedly installed on the synchronous shaft 1302, a synchronous gear 1304 is fixedly installed at the end of the synchronous shaft 1302, a toothed plate 1305 is fixedly installed on the output shaft of the small electric push rod 1301, the toothed plate 1305 is located on the front of the synchronous gear 1304 and meshes with the synchronous gear 1304.

[0054] The miniature electric actuator 1301 is connected to the processor 6 via a signal. The processor 6 controls the operation of the miniature electric actuator 1301 to change the direction of part of the rising airflow by comparing the set threshold with the status signal.

[0055] In this invention, when the temperature sensor 8 detects that the internal temperature of the transformer housing 1 continues to rise after the dual-channel heat dissipation is activated and exceeds the extreme high temperature threshold, the processor 6 automatically controls all airflow guiding structures 13 to start synchronously. The small electric push rod 1301 drives the toothed plate 1305 at the output end to move horizontally. The toothed plate 1305 synchronously meshes and drives all the equidistant synchronous gears 1304 to rotate. Then, through the synchronous shaft 1302, all the air guide plates 1303 are synchronously deflected and tilted, so that the part of the originally vertically upward forced convection airflow is directly guided to the surface of the heat dissipation fins 12 facing the outside of the phase change heat storage structure 5. The high-speed flowing low-temperature fresh air directly washes and exchanges heat on the heat dissipation fins 12, quickly removing the heat accumulated on the surface of the fins. It forms a two-way heat dissipation channel with the nitrogen circulation cooling inside the phase change heat storage material layer 503, which greatly improves the overall heat exchange efficiency under extreme conditions and completely avoids the problem of local hot spot accumulation inside the transformer housing 1.

[0056] The above description is merely a preferred embodiment of the present invention; however, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and its improved concepts, should be covered within the scope of protection of the present invention.

Claims

1. A transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling, comprising a transformer substation housing (1) and a transformer body (2) installed inside it, characterized in that: The interior of the transformer housing (1) is provided with a uniformly distributed forced convection structure (3) and an inert gas circulating heat conduction structure (4), and the exterior of the transformer body (2) is provided with a uniformly distributed phase change heat storage structure (5). The inert gas circulating heat conduction structure (4) is used in conjunction with the phase change heat storage structure (5). The forced convection structure (3) includes a top air trough (301) and a bottom air trough (302). The top air trough (301) and the bottom air trough (302) are respectively opened at the top and bottom of the transformer housing (1) and are connected to the interior of the transformer housing (1). The top air trough (301) is located on the vertical line at the top of the bottom air trough (302). An exhaust axial flow fan (303) is installed on the inner wall of the top air trough (301), and an intake axial flow fan (304) is fixedly installed on the inner wall of the bottom air trough (302). The phase change thermal storage structure (5) includes a heat insulation box (501), which is detachably connected to the transformer body (2) by bolts. A heat-conducting plate (502) is encapsulated at the opening of the heat insulation box (501) close to the transformer body (2). The interior of the heat insulation box (501) is isolated into a closed space by the heat-conducting plate (502). The heat-conducting plate (502) is attached to the heat-generating position of the transformer body (2). The interior of the heat insulation box (501) is filled with a phase change thermal storage material layer (503). The phase change thermal storage material layer (503) is a paraffin organic PCM, which has been thermally enhanced and flame-retardant modified. The inert gas circulating heat conduction structure (4) includes a circulating refrigeration box (401), which is fixedly installed on the inner top wall of the transformer housing (1). A refrigeration chamber (402) is provided inside the circulating refrigeration box (401). A semiconductor refrigeration chip (403) is fixedly installed on the inner wall of the refrigeration chamber (402). The heat dissipation end of the semiconductor refrigeration chip (403) extends through and to the top of the transformer housing (1). A uniformly distributed airflow baffle (404) is connected to the inner wall of the refrigeration chamber (402). Adjacent airflow baffles (404) are staggered to form an airflow channel to extend the contact time between the airflow and the semiconductor refrigeration chip (403). A device connected to the interior of the refrigeration chamber (402) is fixedly installed on the inner wall of the circulating refrigeration box (401). The circulating pump (405) is connected to the heat insulation box (501), and a bent heat conduction pipe (406) is provided inside the heat insulation box (501). The bent heat conduction pipe (406) is in a continuous bent state and is in contact with the phase change heat storage material layer (503). Both ends of the bent heat conduction pipe (406) are connected through and extend to the top of the heat insulation box (501). A supply pipe (407) is connected to the circulating pump (405), and a return pipe (408) is connected to the inner wall of the refrigeration chamber (402). The bottom ends of the supply pipe (407) and the return pipe (408) are respectively connected to the two ends of the bent heat conduction pipe (406). The refrigeration chamber (402), the circulating pump (405), the supply pipe (407), the bent heat conduction pipe (406) and the return pipe (408) constitute a circulation system and are filled with nitrogen. The transformer housing (1) integrates a processor (6) and a signal transmission module (7). The signal transmission module (7) is used to realize the signal connection and transmission between the background and the processor (6). The transformer housing (1) integrates uniformly distributed temperature sensors (8). The temperature sensors (8) are used to obtain the temperature values ​​of each installation position inside the transformer housing (1) and transmit them to the processor (6). The processor (6) controls the opening and closing and power of the intake axial flow fan (304) and the exhaust axial flow fan (303) by comparing the threshold set by the background with the obtained temperature sensor (8) values. A status sensor (9) is installed on the inner wall of the heat insulation box (501). The status sensor (9) is used to acquire the status signal of the phase change heat storage material layer (503) and transmit it to the processor (6). The processor (6) controls the opening and closing and power of the circulation pump (405) and the semiconductor cooling chip (403) by comparing the acquired status signal with the threshold set in the background.

2. The transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to claim 1, characterized in that: An electric heating plate (10) is fixedly installed on the inner bottom wall of the heat insulation box (501). The electric heating plate (10) is in contact with the phase change heat storage material layer (503) at the bottom. The electric heating plate (10) is signal connected to the processor (6) and linked with the status sensor (9).

3. The transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to claim 1, characterized in that: The top and bottom of the transformer housing (1) are detachably connected with dustproof nets (11). The dustproof net (11) on the top shields and protects the top air slot (301) and the semiconductor cooling chip (403), while the dustproof net (11) on the bottom shields the bottom air slot (302).

4. The transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to claim 1, characterized in that: The heat insulation box (501) is connected to a side away from the transformer body (2) with uniformly distributed heat dissipation fins (12), and the ends of the heat dissipation fins (12) are in contact with the phase change heat storage material layer (503) inside the heat insulation box (501).

5. The transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to claim 1, characterized in that: The interior of the transformer substation housing (1) is provided with a uniformly distributed airflow guiding structure (13). The airflow guiding structure (13) includes a small electric push rod (1301). The small electric push rod (1301) is installed on the inner wall of the transformer substation housing (1). The inner wall of the transformer substation housing (1) is rotatably connected with synchronous shafts (1302) arranged at equal distances. A guide plate (1303) is fixedly installed on the synchronous shaft (1302). A synchronous gear (1304) is fixedly installed at the end of the synchronous shaft (1302). A toothed plate (1305) is fixedly installed on the output shaft of the small electric push rod (1301). The toothed plate (1305) is located on the front of the synchronous gear (1304) and meshes with the synchronous gear (1304). The small electric push rod (1301) is connected to the processor (6) by signal. The processor (6) controls the operation of the small electric push rod (1301) to change the direction of part of the rising airflow by comparing the set threshold with the status signal.

6. The transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to claim 1, characterized in that: Both the supply pipe (407) and the return pipe (408) are flexible hoses made of heat-insulating material, and are detachably connected to the top of the bottom bent heat-conducting pipe (406) via a threaded sleeve.

7. The transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to claim 1, characterized in that: A pressure sensor (14) is fixedly installed on the inner wall of the cooling chamber (402). The pressure sensor (14) is connected to the processor (6) via signal. The pressure sensor (14) is used to obtain the pressure value of nitrogen inside the circulation system of the cooling chamber (402) and transmit it to the processor (6). The processor (6) compares the obtained pressure value with the background threshold and transmits it to the background.

8. The operation method of the transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to claim 1, applicable to the transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to any one of claims 1-7, includes the following steps: S1. After the system is powered on for the first time, it automatically completes the self-test of all components. All temperature sensors (8), status sensors (9), and air pressure sensors (14) complete signal calibration in sequence. The background sends the fan start / stop threshold, phase change material phase change state judgment threshold, nitrogen circulation system air pressure alarm threshold and other operating parameters to the processor (6) through the signal transmission module (7). The dustproof nets (11) on the top and bottom of the transformer housing (1) completely block the air inlet and outlet positions. The system enters the real-time monitoring standby state. S2. Under normal low load conditions, the temperature sensor (8) collects the temperature values ​​inside the box in real time at all points and uploads them to the processor (6) for comparison. When the temperature inside the box is within the normal working range, the processor (6) controls the intake axial flow fan (304) at the bottom air slot (302) to start drawing in outside air, and the exhaust axial flow fan (303) at the top air slot (301) starts to discharge hot air, forming a vertical forced convection air duct with bottom inlet and top outlet. The processor (6) dynamically adjusts the operating power of the two fans according to the real-time temperature. The speed is reduced when the load is low and increased to full power when the temperature is close to the first-level temperature control threshold. S3. When the transformer body (2) experiences a short-term overload or an extreme ambient temperature rises, the high thermal conductivity heat-conducting plate (502) attached to the heating surface introduces heat into the phase change heat storage material layer (503) inside the insulation box (501). The paraffin organic PCM absorbs latent heat at the phase change temperature point and transforms from solid to liquid. When the temperature inside the box drops, the phase change heat storage material layer (503) releases heat to the flowing air through the high thermal conductivity heat dissipation fins (12) on the outside, solidifies and restores its heat storage capacity, and the semi-enclosed insulation box (501) prevents heat from diffusing in the opposite direction. S4. When the status sensor (9) shows that the phase change thermal storage material layer (503) remains in a molten state for a long time and cannot solidify, and the temperature inside the chamber uploaded by the temperature sensor (8) continues to exceed the secondary temperature control threshold, the processor (6) triggers the inert gas circulation heat conduction structure (4) to start: the semiconductor cooling chip (403) is powered on, the heat dissipation end dissipates heat to the outside of the chamber, the cold end cools the circulating nitrogen in the cooling chamber (402), the circulation pump (405) drives the nitrogen through the supply pipe (407) into the continuous bending heat conduction pipe (406) inside each phase change thermal storage structure (5), flows through the phase change thermal storage material layer (503) to carry away the latent heat, so that it cools down and solidifies; the pressure sensor (14) monitors the air pressure of the circulation system in real time, and when it is lower than the alarm threshold, the processor (6) pushes a fault alarm to the remote background through the signal transmission module (7); S5. When the temperature continues to rise beyond the extreme high temperature threshold after the above dual-path heat dissipation is started, the processor (6) controls all airflow guiding structures (13) to start: the small electric push rod (1301) drives the toothed plate (1305) to move horizontally, the toothed plate (1305) meshes with the synchronous gear (1304) to rotate, and drives the air guide plate (1303) to deflect through the synchronous shaft (1302), directing part of the forced convection airflow to the surface of the heat dissipation fins (12) facing the outside of the phase change heat storage structure (5), forming a bidirectional heat dissipation with the internal nitrogen circulation.

9. The transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to claim 8, characterized in that: When the winter low temperature starts or the remote background predicts a short-term peak overload, the status sensor (9) detects that the phase change heat storage material layer (503) is completely solid. The processor (6) controls the electric heating plate (10) at the bottom of the corresponding heat insulation box (501) to start with low power for a short time, pre-melt the bottom part of the paraffin phase change material, and reserve the latent heat storage space.

10. The transformer substation heat dissipation system based on phase change thermal storage and forced convection coupling according to claim 8, characterized in that: Throughout the entire operating cycle, the system will upload temperature data, phase change material status data, nitrogen circulation system pressure data, and operating status of each actuator to the remote operation and maintenance backend in real time via the signal transmission module (7), supporting remote adjustment of operating thresholds and retrieval of historical data; the supply pipe (407) and return pipe (408) adopt a detachable quick-connect structure with heat-insulated hoses and threaded sleeves, and the dustproof net (11) adopts a detachable design for easy maintenance; the system operates through phase change heat storage, forced convection, inert gas circulation, and wind-guided enhanced multi-layer coupling.

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