A power grid transformer protection device

Abstract

The application belongs to the technical field of power transformers, and discloses a power grid transformer protection device, which comprises a transformer body, a heat dissipation shell is mounted on the surface of the transformer body, a wind box is arranged on the top of the surface of the transformer body, the wind box is located on the top of the heat dissipation shell, heat dissipation fans are in communication with the front side and the rear side of the top of the wind box, and an air inlet filter screen is mounted on the bottom of the heat dissipation shell. When the temperature of transformer oil rises to a set value, the medium-temperature shape memory elastic sheet is heated and shrinks, drives the wind box to move downward along the sliding rod through the sliding block, triggers the heat dissipation fan to start after the multi-section travel switch at the bottom of the wind box contacts the connecting plate, air forms a forced convection channel to efficiently dissipate heat, when the temperature of the oil drops to the set value, the medium-temperature shape memory elastic sheet is elongated and reset, pushes the wind box to rise, the multi-section travel switch is disconnected, the heat dissipation fan stops running, and the natural heat dissipation mode is restored, so that the self-adapting heat dissipation to load change is realized, and the energy-saving effect is remarkable.

Description

Technical Field

[0001] This invention relates to the field of power transformer technology, specifically a power grid transformer protection device. Background Technology

[0002] Transformers are key equipment in power systems that undertake the core functions of voltage transformation, power transmission and distribution. Their operational stability directly determines the reliability and safety level of the power grid. During operation, oil-immersed transformers continuously generate a large amount of heat due to core hysteresis loss, eddy current loss and winding copper loss. If the heat cannot be dissipated in a timely and effective manner, it will lead to excessively high oil temperature at the top of the transformer, accelerated aging of insulation materials, and deterioration and decomposition of insulating oil. In severe cases, it can cause major power accidents such as winding deformation, insulation breakdown or even oil tank explosion, resulting in large-scale power outages and huge economic losses.

[0003] Currently, most existing oil-immersed transformers adopt a single natural heat dissipation mode, relying on the heat exchange between the heat dissipation fins and the air through natural convection. The heat dissipation efficiency is limited and can only be adapted to low load conditions. When the temperature is high in summer or the transformer is under high load or overload, the oil temperature is prone to exceed the standard. At the same time, traditional heat dissipation structures are mostly single-stage forced air cooling, which cannot adjust the fan operation status according to the oil temperature, resulting in high energy consumption and rapid component wear. Summary of the Invention

[0004] To address the above problems, the present invention provides the following technical solution: The transformer includes a transformer body, a heat dissipation shell mounted on the surface of the transformer body, a wind box fitted on the top of the surface of the transformer body, the wind box being located on top of the heat dissipation shell, cooling fans connected to both the front and rear sides of the top of the wind box, and an air inlet filter installed at the bottom of the heat dissipation shell. It also includes: Temperature-sensitive heat sinks are installed inside the air box and are used to actively cool the heat sink housing. The temperature-changing heat dissipation component includes connecting plates installed around the surface of the heat dissipation shell. A sliding rod is installed on the top of the connecting plate, and the top of the sliding rod is installed on the surface of the transformer body. Slider blocks are fixedly connected around the perimeter of the air box, and the sliders are fitted onto the surface of the sliding rod. A medium-temperature shape memory spring is installed on the top of the connecting plate, and the top of the medium-temperature shape memory spring is installed on the surface of the transformer body. An exhaust filter is installed at the bottom of the cooling fan. Multi-stage limit switches are installed at the four corners of the bottom of the air box. The multi-stage limit switches are located on the top of the connecting plate and are used in conjunction with the cooling fan. A high-temperature shape memory spring is installed on the top of the connecting plate, and the top of the high-temperature shape memory spring is installed on the surface of the transformer body. The transformer body utilizes the hot airflow for heat dissipation and dust removal through an air jet component. The heat dissipation channel switching component is installed on the inside of the heat dissipation housing and is used to switch the heat dissipation mode of the heat dissipation housing.

[0005] In the above technical solution, the heat dissipation channel switching component includes a vertical plate installed on the top of the inner wall of the air box. The bottom of the vertical plate extends into the interior of the heat dissipation housing. A rocker arm is provided inside the vertical plate. The side of the rocker arm near the heat dissipation housing is hinged to the surface of the heat dissipation housing via a connecting block and a shaft pin. Sliding sleeves are installed around the heat dissipation housing. A positioning rod is slidably connected inside the sliding sleeve. A frame is provided around the heat dissipation housing. The surface of the positioning rod is mounted on the surface of the frame. A movable sealing plate is installed on the surface of the frame. The movable sealing plate is located inside the heat dissipation housing. A retainer sleeve is fitted onto the surface of the rocker arm. The surface of the retainer sleeve is fixedly connected to the surface of the movable sealing plate. A follow-up dust removal component is provided inside the heat dissipation housing.

[0006] In the above technical solution, the follow-up dust removal component includes a scraper installed on the surface of the movable sealing plate. The surface of the scraper is in contact with the surface of the heat dissipation housing. A dust baffle is installed on the surface of the movable sealing plate. The dust baffle is located on top of the air inlet filter. Auxiliary heat dissipation fins are installed on the surface of the movable sealing plate. Follow-up air guides are installed on the front and rear sides of the top of the transformer body.

[0007] In the above technical solution, the follow-up air guide includes toothed plates fixedly installed on the front and rear sides of the top of the air box. The top of the front and rear sides of the transformer body are both hinged with air guide covers through connecting blocks and shaft pins. Gears are installed inside the air guide covers, and the gears mesh with the toothed plates. The air guide covers are located on the top of the exhaust diversion hood.

[0008] In the above technical solution, the jet component includes a heat dissipation and dust removal jet frame, which is fixedly installed on the heat dissipation housing. An impurity blowing frame is installed at the bottom of the surface of the heat dissipation housing. An exhaust diversion hood is installed on the top of the heat dissipation fan. The output end of the exhaust diversion hood is connected to the heat dissipation and dust removal jet frame. The heat dissipation and dust removal jet frame is connected to the impurity blowing frame through a pipe. The air guide cover is located on the top of the exhaust diversion hood.

[0009] In the above technical solution, limit plates are installed at the four corners of the top of the transformer body. The limit plates are located at the top of the follow-up air guide. A buffer pad is installed at the top of the air box, and a sealing pad is installed at the bottom of the air box.

[0010] In the above technical solution, the surface of the rocker is inlaid with reinforcing strips.

[0011] In the above technical solution, a wear-resistant sleeve is installed on the surface of the rocker, and the surface of the wear-resistant sleeve is in contact with the inner wall of the ferrule.

[0012] In the above technical solution, a limiting plate is sleeved on the surface of the vertical plate, and the surface of the limiting plate is mounted on the surface of the heat dissipation shell.

[0013] In the above technical solution, a limiting block is installed on the surface of the positioning rod, and the limiting block is slidably connected inside the sliding sleeve.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes a dual-temperature-sensitive drive structure with medium-temperature and high-temperature shape memory springs, combined with a multi-stage limit switch, to achieve two-stage cooling at medium and high temperatures based on the transformer oil temperature. In the medium-temperature range, low-power forced air cooling is activated, while in the high-temperature range, full-load forced air cooling is switched. When the oil temperature drops, the mechanism resets step by step, effectively avoiding frequent start-stop of the cooling fan, reducing mechanical wear and operating energy consumption, and adapting to different transformer load conditions.

[0015] Furthermore, when the bellows moves downwards with the contraction of the medium-temperature shape memory spring, the vertical plate simultaneously presses down on the free end of the rocker, causing the rocker to rotate around the pivot pin. Through the ferrule, the movable sealing plate moves along the trajectory defined by the sliding sleeve and the positioning rod to the outside of the heat dissipation shell, sealing the surface gap of the heat dissipation shell and forming a closed forced convection channel from bottom air intake to top air exhaust. When the bellows rises and resets, the vertical plate lifts up and causes the rocker to rotate in the opposite direction. The movable sealing plate resets simultaneously, restoring open natural heat dissipation without additional drive and control, thus improving the local airflow swirl phenomenon in the single natural heat dissipation mode.

[0016] Furthermore, when the movable sealing plate moves horizontally with the rocker, the scraper and dust baffle move synchronously with the auxiliary heat dissipation fins. During high-temperature forced heat dissipation, the movable sealing plate moves outward, the scraper scrapes along the surface of the heat dissipation shell to remove accumulated dust and catkins, the dust baffle blocks large particles of debris from entering the air inlet filter, and the auxiliary heat dissipation fins perform auxiliary heat exchange. During low-temperature reset, the scraper reverses and scrapes away residual dust a second time, thus achieving automatic dust removal by switching the heat dissipation mode and keeping the heat dissipation shell clean. Attached Figure Description

[0017] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings; Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the movable sealing plate of the present invention; Figure 3 This is a schematic diagram of the exhaust manifold of the present invention; Figure 4 This is a schematic diagram of the structure of the heat dissipation and dust removal jet frame of the present invention; Figure 5 This is a schematic diagram of the rocker arm of the present invention; Figure 6 This is a schematic diagram of the structure of the follower air guide in this invention; Figure 7 This is a schematic diagram of the structure of the heat dissipation channel switching component of the present invention; Figure 8 This is a schematic diagram of the structure of the bellows of the present invention. Figure 9 For the present invention Figure 2 Enlarged structural diagram at point A in the middle.

[0018] In the diagram: 1. Transformer body; 2. Heat sink housing; 3. Air box; 4. Cooling fan; 5. Inlet filter; 6. Temperature-sensitive heat sink; 61. Connecting plate; 62. Slide rod; 63. Slider; 64. Medium-temperature shape memory spring; 65. Exhaust filter; 66. Multi-stage limit switch; 67. High-temperature shape memory spring; 68. Air jet component; 681. Heat dissipation and dust removal air jet frame; 682. Impurity blowing frame; 683. Exhaust duct hood; 7. Heat dissipation channel switching component; 71. Vertical plate; 72. Rocker plate; 73. Sliding sleeve; 74. Positioning rod; 75. Frame; 76. Movable sealing plate; 77. Sleeve; 8. Follow-up dust removal component; 81. Scraper; 82. Dust baffle; 83. Auxiliary heat dissipation fins; 9. Follow-up air guide component; 91. Toothed plate; 92. Air guide cover plate; 93. Gear; 10. Limiting plate; 11. Buffer pad; 12. Sealing gasket; 13. Reinforcing strip; 14. Wear-resistant sleeve; 15. Limiting clamping plate; 16. Limiting block. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] like Figures 1 to 6 As shown, the present invention provides a power grid transformer protection device, including a transformer body 1, a heat dissipation shell 2 installed on the surface of the transformer body 1, a wind box 3 sleeved on the top of the surface of the transformer body 1, the wind box 3 being located on top of the heat dissipation shell 2, and cooling fans 4 connected to both the front and rear sides of the top of the wind box 3. An air inlet filter 5 is installed at the bottom of the heat dissipation shell 2. The device is characterized by further comprising: Temperature-sensitive heat sink 6 is installed inside the air box 3 and is used to actively cool the heat sink housing 2. The temperature-sensitive heat sink 6 includes a connecting plate 61 installed around the surface of the heat sink housing 2. A slide rod 62 is installed on the top of the connecting plate 61, and the top of the slide rod 62 is installed on the surface of the transformer body 1. Slider blocks 63 are fixedly connected around the wind box 3, and the sliders 63 are fitted onto the surface of the slide rod 62. A medium-temperature shape memory spring 64 is installed on the top of the connecting plate 61, and the top of the medium-temperature shape memory spring 64 is installed on the surface of the transformer body 1. An exhaust filter 65 is installed at the bottom of the cooling fan 4. Multi-stage limit switches 66 are installed at the four corners of the bottom of the wind box 3. The multi-stage limit switches 66 are located on the top of the connecting plate 61 and are used in conjunction with the cooling fan 4. A high-temperature shape memory spring 67 is installed on the top of the connecting plate 61, and the top of the high-temperature shape memory spring 67 is installed on the surface of the transformer body 1. The transformer body 1 utilizes the hot airflow for heat dissipation and dust removal through the jet 68.

[0021] Specifically, the medium-temperature shape memory spring 64 is a common two-way nickel-titanium shape memory alloy spring. Its austenitic phase transformation completion temperature in the fully contracted state is 65 degrees Celsius, and its martensitic phase transformation completion temperature in the fully extended and reset state is 45 degrees Celsius. It is the core temperature-sensitive drive element for the medium-temperature range, deforming in response to oil temperature changes within the medium-temperature range to provide the first stage of driving force for the downward movement of the bellows 3. The high-temperature shape memory spring 67 is also a common two-way nickel-titanium shape memory alloy spring. Its austenitic phase transformation completion temperature in the fully contracted state is 78 degrees Celsius, and its martensitic phase transformation completion temperature in the fully extended and reset state is 58 degrees Celsius. Its phase transformation trigger temperature is higher than that of the medium-temperature shape memory spring 64, and it superimposes the deformation force in the high-temperature oil temperature range to achieve graded control of the bellows 3's stroke. Both the medium-temperature shape memory spring 64 and the high-temperature shape memory spring 67 have a thickness of 1.8 mm, a width of 25 mm, and a straight length of 120 mm. The air box 3 is pre-bent into an arc shape with an initial arch height of 25 mm, and its restoring force can meet the load drive requirements. The multi-stage limit switch 66 is a commercially available multi-position direct-acting limit switch, which can trigger different contacts according to the downward stroke of the air box 3 to accurately switch the operating speed of the cooling fan 4. The connecting plate 61 is the bottom support mounting base, and also undertakes multiple functions such as fixing the slide rod 62 and triggering the multi-stage limit switch 66. The slide rod 62 is a commercially available standard industrial linear optical shaft, which is used in conjunction with the slider 63 to provide stable vertical motion guidance for the air box 3 and prevent deviation and jamming during the lifting process. The slider 63 is a commercially available standard linear motion slider, which is fixedly installed on the side wall of the air box 3 and slides along the surface of the slide rod 62 to ensure that the lifting action of the air box 3 is smooth and stable. The exhaust filter 65 is installed on the air inlet side of the cooling fan 4 to filter the impeller of the cooling fan 4, and prevent impurities from jamming the impeller of the cooling fan 4 and causing equipment damage.

[0022] like Figures 1 to 5As shown, the heat dissipation channel switching component 7 is installed inside the heat dissipation housing 2 and is used to switch the heat dissipation mode of the heat dissipation housing 2. The heat dissipation channel switching component 7 includes a vertical plate 71 installed on the top of the inner wall of the air box 3. The bottom of the vertical plate 71 extends into the interior of the heat dissipation housing 2. A rocker plate 72 is provided inside the vertical plate 71. The side of the rocker plate 72 near the heat dissipation housing 2 is hinged to the surface of the heat dissipation housing 2 by a connecting block and a shaft pin. Sliding sleeves 73 are installed around the heat dissipation housing 2. A positioning rod 74 is slidably connected inside the sliding sleeve 73. A frame 75 is provided around the heat dissipation housing 2. The surface of the positioning rod 74 is installed on the surface of the frame 75. A movable sealing plate 76 is installed on the surface of the frame 75. The movable sealing plate 76 is located inside the heat dissipation housing 2. A retaining sleeve 77 is fitted on the surface of the rocker plate 72. The surface of the retaining sleeve 77 is fixedly connected to the surface of the movable sealing plate 76.

[0023] Specifically, the vertical plate 71 is installed on the top of the inner wall of the air box 3 and rises and falls synchronously with the air box 3. It is the power input component of the heat dissipation channel switching component 7, transmitting the vertical movement of the air box 3 to the rocker plate 72. The rocker plate 72 is hinged to the surface of the heat dissipation housing 2 through a shaft pin. As a force conversion and amplification component, it converts the vertical linear movement of the vertical plate 71 into the horizontal linear movement of the movable sealing plate 76. The sliding sleeve 73 is a standard industrial linear sliding sleeve, which cooperates with the positioning rod 74 to provide precise horizontal movement guidance for the movable sealing plate 76 and prevent the movable sealing plate 76 from deviating or getting stuck during movement. The frame 75 is used to fix the movable sealing plate 76, distribute the force during the transmission process, and prevent the movable sealing plate 76 from deforming and affecting the sealing effect. The movable sealing plate 76 is the core execution component. By moving to close or open the outer gap of the heat dissipation housing 2, the heat dissipation channel is switched. The clamp 77 is sleeved on the surface of the rocker plate 72 and fixedly connected to the movable sealing plate 76 to achieve gapless transmission between the rocker plate 72 and the sealing plate, ensuring the synchronization of the action.

[0024] like Figures 1 to 7 As shown, the heat dissipation housing 2 is provided with a follow-up dust removal component 8. The follow-up dust removal component 8 includes a scraper 81 installed on the surface of the movable sealing plate 76. The surface of the scraper 81 is in contact with the surface of the heat dissipation housing 2. A dust baffle 82 is installed on the surface of the movable sealing plate 76. The dust baffle 82 is located on top of the air inlet filter 5. An auxiliary heat dissipation fin 83 is installed on the surface of the movable sealing plate 76.

[0025] Specifically, the scraper 81 is a common industrial rubber scraper on the market, installed on the edge of the movable sealing plate 76. Its surface is in close contact with the heat dissipation housing 2. By reciprocating with the movable sealing plate 76, it scrapes away dust, catkins, insects and other debris attached to the surface of the heat dissipation housing 2 in both directions, effectively eliminating the increase in thermal resistance caused by dust accumulation, and eliminating the need for regular manual cleaning. The dust baffle 82 is a rectangular metal baffle, fixed at the bottom of the movable sealing plate 76. When the air is naturally cooled, it blocks the area above the air intake filter 5 to prevent large particles such as leaves and plastic pieces from entering the air intake filter 5.

[0026] like Figures 1 to 6 As shown, follower air guides 9 are installed on the front and rear sides of the top of the transformer body 1. The follower air guides 9 include toothed plates 91 fixedly installed on the front and rear sides of the top of the air box 3. Air guide covers 92 are hinged to the top of the front and rear sides of the transformer body 1 through connecting blocks and shaft pins. Gears 93 are installed inside the air guide covers 92. The gears 93 mesh with the toothed plates 91. The air guide covers 92 are located on the top of the exhaust diversion hood 683.

[0027] Specifically, the gear plate 91 is a common standard industrial spur rack, vertically fixedly installed on the top of the air box 3, and rises and falls smoothly and synchronously with the air box 3. It is the power input component of the follower air guide 9, and maintains precise meshing with the gear 93 throughout the lifting process. Through tooth surface meshing, the vertical linear motion of the air box 3 is stably converted into the rotational motion of the gear 93. The gear 93 is a standard cylindrical spur gear, fixedly embedded at the hinge shaft of the air guide cover 92 with an interference fit. It does not rotate relative to the hinge shaft, and the angle transmission is precise when meshing with the gear plate 91. It can drive the air guide cover 92 to achieve synchronous rotation that strictly corresponds to the lifting stroke of the air box 3. The transmission is smooth and the transmission ratio is stable. The air guide cover 92 has excellent electrical insulation performance and outdoor weather resistance, which can prevent the induced electricity generated by the high voltage part of the transformer from being conducted to the air guide cover. The surface of plate 92 poses a safety hazard and is not prone to aging, cracking, deformation, or failure when exposed to high and low temperatures and ultraviolet radiation outdoors for a long time. It is hinged to the top of the transformer body 1 by a shaft pin. When open, it can guide the hot airflow discharged by the cooling fan to diffuse rapidly and diagonally upwards to the surrounding airspace, avoiding the accumulation of hot air on the top of the transformer body 1 to form a heat island effect and prevent exhaust air from being drawn back into the air duct, reducing the heat dissipation efficiency. When closed, it completely covers the top opening of the exhaust diversion hood 683, forming a tight physical barrier to prevent rainwater, dust, fallen leaves, flying insects, and other debris from entering the air duct of the cooling fan 4 and the heat dissipation shell 2. At the same time, it can prevent snow and ice from blocking the exhaust channel in winter, effectively protecting the internal cooling fan 4, exhaust filter 65, and other components from corrosion by the complex outdoor environment and extending the overall service life of the equipment.

[0028] like Figures 2 to 3As shown, the jet component 68 includes a heat dissipation and dust removal jet frame 681, which is fixedly installed on the heat dissipation housing 2. An impurity removal frame 682 is installed at the bottom of the surface of the heat dissipation housing 2. An exhaust diversion hood 683 is installed on the top of the heat dissipation fan 4. The output end of the exhaust diversion hood 683 is connected to the heat dissipation and dust removal jet frame 681. The heat dissipation and dust removal jet frame 681 is connected to the impurity removal frame 682 through a through pipe. The air guide cover 92 is located on the top of the exhaust diversion hood 683.

[0029] Specifically, the jet component 68, as the core hub for the reuse of exhaust energy in this solution, establishes a mechanical and fluid coupling relationship with the temperature-changing heat sink 6, the heat dissipation channel switching component 7, and the follow-up air guide component 9. When the oil temperature rises, it drives the medium-temperature shape memory spring 64 and the high-temperature shape memory spring 67 to contract and drive the air box 3 downward. At the same time, the exhaust diversion hood 683 is connected to the circuit synchronously with the cooling fan 4. When the multi-stage limit switch 66 triggers the operation of the cooling fan 4 according to the oil temperature level, the exhaust diversion hood 683 immediately diverts the generated forced convection airflow proportionally. One path is sprayed out by the high-pressure airflow through the heat dissipation dust removal jet frame 681 arranged circumferentially on the top of the heat sink shell 2 to blow away the dust accumulated on the auxiliary heat dissipation fins 83 from top to bottom. The other path is introduced through the pipe. The impurity blowing frame 682 at the bottom blows the bottom of the air inlet filter 5 from the outside to the inside, cleaning the impurities adsorbed at the bottom of the air inlet filter 5. At the same time, the vertical plate 71 presses down the rocker plate 72, which drives the movable sealing plate 76 to close the gap of the heat dissipation shell 2 to form a closed air duct. This achieves a seamless process of cleaning first, sealing then cooling. Meanwhile, the air guide cover 92 flips open under the meshing drive of the toothed plate 91 and the gear 93, so that the hot airflow is directed to the upper side to eliminate the heat island effect and prevent airflow short circuit. It also provides carrying power for the dust blown down. The entire dust removal process is driven entirely by the waste kinetic energy discharged by the heat dissipation fan 4. No additional air source or electronic control components are required, achieving on-demand cleaning and zero-power self-maintenance related to heat dissipation load.

[0030] like Figures 2 to 5 As shown, limit plates 10 are installed at the four corners of the top of the transformer body 1. The limit plates 10 are located on the top of the follower air guide 9. A buffer pad 11 is installed on the top of the air box 3. A sealing pad 12 is installed on the bottom of the air box 3. A reinforcing strip 13 is inlaid on the surface of the rocker plate 72. A wear-resistant sleeve 14 is installed on the surface of the rocker plate 72. The surface of the wear-resistant sleeve 14 contacts the inner wall of the sleeve 77. A limit plate 15 is sleeved on the surface of the vertical plate 71. The surface of the limit plate 15 is installed on the surface of the heat dissipation shell 2. A limit block 16 is installed on the surface of the positioning rod 74. The limit block 16 is slidably connected to the inside of the sliding sleeve 73.

[0031] Specifically, the limiting plate 10 is fixedly installed at the four corners of the top of the transformer body 1, located on the top of the follower air guide 9, to limit the maximum flipping stroke of the air guide cover 92, prevent the air guide cover 92 from excessively rotating and getting stuck or dislodged, and ensure the stability of the meshing transmission between the toothed plate 91 and the gear 93; the buffer pad 11 is a commercially available general-purpose industrial rubber buffer pad, fixedly installed on the top of the air box 3, and contacts the transformer body 1 when the air box 3 rises and resets, absorbing impact energy, eliminating mechanical collision noise, and preventing damage to the air box 3 and its internal components due to impact; the sealing gasket 12 is a commercially available general-purpose silicone rubber flat sealing gasket, fixedly installed at the bottom of the air box 3, and tightly fits the top end face of the heat dissipation shell 2 in the forced heat dissipation mode, filling the connection gap, realizing the airtight connection of the air duct, preventing airflow leakage, ensuring stable air pressure in the air duct, and improving the forced convection heat transfer efficiency; the reinforcing strip 13 is a common standard flat steel reinforcing strip, embedded in the surface of the rocker plate 72, significantly improving the bending strength and torsional stiffness of the rocker plate 72, preventing the rocker plate 72 from being damaged by impact. The bending deformation that occurs during long-term reciprocating transmission under stress ensures transmission accuracy and operational reliability. The wear-resistant sleeve 14 is a commercially available general-purpose industrial nylon wear-resistant sleeve, which is fixedly installed on the contact surface between the rocker plate 72 and the ferrule 77, significantly reducing the coefficient of friction when the two slide relative to each other, reducing transmission wear, extending the service life of the rocker plate 72 and the ferrule 77, and reducing the risk of jamming during long-term operation. The limiting plate 15 is a customized U-shaped metal plate, which is fixedly installed on the surface of the heat dissipation housing 2 and sleeved on the outside of the vertical plate 71, limiting the lateral displacement and sway of the vertical plate 71, preventing the vertical plate 71 from shifting during lifting and lowering, which would cause uneven force on the rocker plate 72, and ensuring that the vertical plate 71 always transmits smoothly in the vertical direction. The limiting block 16 is a commercially available standard shaft elastic retaining ring, which is fixedly installed on the surface of the positioning rod 74 and slidably connected inside the sliding sleeve 73, used to limit the maximum sliding stroke of the positioning rod 74 in the sliding sleeve 73, preventing the movable sealing plate 76 from moving excessively and detaching from the guide rail or colliding with surrounding components, and ensuring accurate action boundaries for switching heat dissipation channels.

[0032] The working principle and usage process of this invention: Under low temperature and low load conditions, the medium temperature shape memory spring 64 and the high temperature shape memory spring 67 are both kept in the extended state, the air box 3 is in the upper position, the multi-stage limit switch 66 is not triggered, the cooling fan 4 is stopped, the movable sealing plate 76 is kept in the position inside the heat dissipation shell 2, the heat dissipation shell 2 is in an open natural heat dissipation state, the air guide cover 92 is closed simultaneously to block the exhaust diversion hood 683, and the dust baffle 82 blocks the air inlet filter 5 from the top to prevent debris from entering; When the transformer oil temperature rises to the medium temperature threshold, the medium temperature shape memory spring 64 contracts due to heat, causing the air box 3 to move slightly downward along the slide rod 62 via the slider 63. The multi-stage limit switch 66 contacts the connecting plate 61, triggering the cooling fan 4 to run at low speed. At the same time, the vertical plate 71 presses down on the rocker plate 72, which moves the movable sealing plate 76 slightly inward along the trajectory defined by the slide sleeve 73 and the positioning rod 74 through the sleeve 77. The scraper 81 moves to initially scrape off the surface dust in the gap outside the semi-enclosed heat sink 2. The toothed plate 91 moves down and engages the gear 93 to partially open the air guide cover 92. The exhaust diversion hood 683 diverts the exhaust air to the heat sink dust removal jet frame 681 and the impurity blowing frame 682, and performs a light airflow purging on the heat sink 2 and the air inlet filter 5. When the oil temperature continues to rise to the high temperature threshold, the high temperature shape memory spring 67 is superimposed and contracted, the air box 3 continues to descend to the maximum stroke, the multi-stage limit switch 66 switches to the high speed, the cooling fan 4 operates at full load, the movable sealing plate 76 seals most of the gap on the outside of the heat sink housing 2, and forms a fully enclosed forced convection air duct with the sealing gasket 12. The heat dissipation dust removal jet frame 681 and the impurity blowing frame 682 simultaneously strengthen the blowing force, and the air guide cover 92 is fully opened to guide the hot airflow to diffuse obliquely and be discharged. As the oil temperature gradually decreases, the medium-temperature shape memory spring 64 and the high-temperature shape memory spring 67 extend and reset in sequence, the air box 3 moves upward step by step, the cooling fan 4 slows down until it stops, all linkage components reset synchronously, and the device returns to the natural cooling state.

[0033] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to any specific implementation. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A power grid transformer protection device, comprising a transformer body (1), a heat dissipation shell (2) installed on the surface of the transformer body (1), a wind box (3) sleeved on the top of the surface of the transformer body (1), the wind box (3) being located on the top of the heat dissipation shell (2), a cooling fan (4) being connected to both the front and rear sides of the top of the wind box (3), and an air inlet filter (5) installed at the bottom of the heat dissipation shell (2), characterized in that, Also includes: Temperature-sensitive heat sink (6) is installed inside the air box (3) and is used to actively cool the heat sink housing (2); The temperature-changing heat sink (6) includes a connecting plate (61) installed around the surface of the heat sink housing (2). A sliding rod (62) is installed on the top of the connecting plate (61). The top of the sliding rod (62) is installed on the surface of the transformer body (1). A slider (63) is fixedly connected around the wind box (3). The slider (63) is sleeved on the surface of the sliding rod (62). A medium-temperature shape memory spring (64) is installed on the top of the connecting plate (61). The top of the medium-temperature shape memory spring (64) is installed on the surface of the transformer body (1). An exhaust filter (65) is installed at the bottom of the heat sink fan (4). A multi-stage limit switch (66) is installed at each of the four corners of the bottom of the wind box (3). The multi-stage limit switch (66) is located on the top of the connecting plate (61). The multi-stage limit switch (66) is used in conjunction with the heat sink fan (4). A high-temperature shape memory spring (67) is installed on the top of the connecting plate (61). The heat dissipation channel switching component (7) is installed on the inside of the heat dissipation housing (2) and is used to switch the heat dissipation mode of the heat dissipation housing (2).

2. The power grid transformer protection device according to claim 1, characterized in that: The heat dissipation channel switching component (7) includes a vertical plate (71) installed on the top of the inner wall of the air box (3). The bottom of the vertical plate (71) extends into the interior of the heat dissipation housing (2). A rocker plate (72) is provided inside the vertical plate (71). The side of the rocker plate (72) near the heat dissipation housing (2) is hinged to the surface of the heat dissipation housing (2) by a connecting block and a shaft pin. Sliding sleeves (73) are installed around the heat dissipation housing (2). A positioning rod (74) is slidably connected inside the sliding sleeve (73). A frame (75) is provided around the heat dissipation housing (2). The surface of the positioning rod (74) is installed on the surface of the frame (75). A movable sealing plate (76) is installed on the surface of the frame (75). The movable sealing plate (76) is located inside the heat dissipation housing (2). A retainer (77) is fitted on the surface of the rocker plate (72). The surface of the retainer (77) is fixedly connected to the surface of the movable sealing plate (76). A follow-up dust removal component (8) is provided inside the heat dissipation housing (2).

3. The power grid transformer protection device according to claim 2, characterized in that: The following dust removal component (8) includes a scraper (81) installed on the surface of the movable sealing plate (76), the surface of the scraper (81) is in contact with the surface of the heat dissipation housing (2), a dust baffle (82) is installed on the surface of the movable sealing plate (76), the dust baffle (82) is located on the top of the air inlet filter (5), an auxiliary heat dissipation fin (83) is installed on the surface of the movable sealing plate (76), and following air guide components (9) are installed on the front and rear sides of the top of the transformer body (1).

4. A power grid transformer protection device according to claim 3, characterized in that: The follow-up air guide (9) includes a toothed plate (91) fixedly installed on the front and rear sides of the top of the air box (3). The top of the front and rear sides of the transformer body (1) are both hinged with air guide covers (92) through connecting blocks and shaft pins. A gear (93) is installed inside the air guide cover (92), and the gear (93) meshes with the toothed plate (91).

5. A power grid transformer protection device according to claim 1, characterized in that: The top of the high-temperature shape memory spring (67) is mounted on the surface of the transformer body (1), and the transformer body (1) utilizes the hot airflow for heat dissipation and dust removal through the jet component (68).

6. A power grid transformer protection device according to claim 5, characterized in that: The jet component (68) includes a heat dissipation and dust removal jet frame (681), which is fixedly installed on the heat dissipation housing (2). An impurity blowing frame (682) is installed at the bottom of the surface of the heat dissipation housing (2). An exhaust diversion hood (683) is installed on the top of the heat dissipation fan (4). The output end of the exhaust diversion hood (683) is connected to the heat dissipation and dust removal jet frame (681). The heat dissipation and dust removal jet frame (681) is connected to the impurity blowing frame (682) through a pipe.

7. A power grid transformer protection device according to claim 1, characterized in that: Limiting plates (10) are installed at the four corners of the top of the transformer body (1). The limiting plates (10) are located at the top of the follow-up air guide (9). A buffer pad (11) is installed at the top of the air box (3). A sealing pad (12) is installed at the bottom of the air box (3).

8. A power grid transformer protection device according to claim 2, characterized in that: The surface of the rocker (72) is inlaid with a reinforcing strip (13), and the surface of the rocker (72) is fitted with a wear-resistant sleeve (14), the surface of the wear-resistant sleeve (14) being in contact with the inner wall of the sleeve (77).

9. A power grid transformer protection device according to claim 2, characterized in that: The surface of the vertical plate (71) is fitted with a limiting plate (15), and the surface of the limiting plate (15) is mounted on the surface of the heat dissipation shell (2).

10. A power grid transformer protection device according to claim 2, characterized in that: A limiting block (16) is installed on the surface of the positioning rod (74), and the limiting block (16) is slidably connected inside the sliding sleeve (73).

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