All-season refrigeration integrated hot rod carrying photovoltaic direct-driven compression device and application method of all-season refrigeration integrated hot rod

Abstract

The invention discloses an all-season refrigeration integrated hot rod carrying a photovoltaic direct-driven micro compression device and an application method. The all-season refrigeration integrated hot rod comprises a hot rod body, a single photovoltaic panel, a micro compressor, a working medium circulating connecting pipe, a working medium circulating pipe and a built-in micro compression device, wherein the built-in micro compression device is directly embedded into a hot rod condensation section; photovoltaic direct drive: a single photovoltaic panel is integrated with a hot rod; the miniature compressor can be directly driven to refrigerate by a single-sided photovoltaic panel; meanwhile, the photovoltaic panel and the condensation section of the hot rod are welded together, so that the condensation section cannot receive solar illumination, and thermal disturbance of heat conduction of the hot rod body to permafrost of the evaporation section is reduced; all-season intelligent temperature control is achieved, and refrigeration requirements are dynamically matched based on automatic start-stop logic of temperature sensing.

Description

Technical Field

[0001] The present invention relates to an integrated heat rod and an application method thereof, and in particular to an all-season refrigeration integrated heat rod equipped with a photovoltaic direct-drive micro-compression device and an application method thereof, belonging to the field of cold region railway subgrade engineering. Background Art

[0002] In recent years, global climate change has led to more frequent extreme weather events in cold regions and accelerated permafrost degradation, posing a serious challenge to railway subgrade stability. Traditional heat rod technology, while effective in cold weather, becomes completely ineffective in warm weather, as the condensing zone temperature exceeds the permafrost, exacerbating the risk of permafrost thaw. Existing improved technologies (such as increasing heat rod density or installing external electric chillers) can partially alleviate this problem, but they suffer from bottlenecks such as high energy consumption, complex structures, and low thermal efficiency. Industry trends indicate an urgent need to develop all-season, low-energy active cooling solutions that combine renewable energy with intelligent temperature control technologies.

[0003] As railway networks expand in high-altitude and cold regions, technologies for maintaining stable permafrost roadbeds throughout the seasons are needed. Railway operators urgently need low-energy, high-reliability solutions to reduce maintenance costs. Ecologically sensitive areas require a reduction in reliance on traditional energy sources and the promotion of renewable energy such as photovoltaics.

[0004] Publication number CN106120506A discloses a prior art system that uses natural temperature differences to drive the working fluid cycle, dissipating heat in cold weather to maintain frozen soil stability. However, this prior art system does not function in warm weather, is dependent on climatic conditions, and cannot cope with extreme temperature increases. Publication number CN110502847A discloses an electrically driven auxiliary cooling hot rod. This prior art system incorporates an external electric refrigerator to extend the cooling cycle. However, this prior art system consumes a lot of energy and requires a continuous power supply. The external device also increases thermal disturbances, reducing system reliability.

[0005] In addition, the prior art also has the following defects:

[0006] 1. Seasonal dependence: Traditional heat rods are only effective in cold seasons, and the thermal stability of frozen soil is out of control in warm seasons.

[0007] 2. Unsustainable energy: Electric drive solutions rely on the power grid or diesel power generation, which has high operation and maintenance costs and is not environmentally friendly.

[0008] 3. Structural complexity: External refrigeration devices increase installation difficulty and are susceptible to harsh environments.

[0009] 4. Loss of thermal efficiency: The external refrigerator is separated from the heat rod, resulting in low cooling transfer efficiency.

[0010] Traditional electric-driven chillers consume an average of 2.5 kW·h of energy per day, with annual operation and maintenance costs exceeding 10,000 yuan. Furthermore, carbon emissions increase by 30% when relying on diesel generators. Summary of the Invention

[0011] To solve the defects existing in the prior art, the present invention discloses an all-season refrigeration integrated heat pipe equipped with a photovoltaic direct-drive micro-compression device, and its technical solution is as follows:

[0012] An all-season refrigeration integrated heat pipe equipped with a photovoltaic direct-drive micro-compression device, comprising a heat pipe body, a working medium circulation connecting pipe and a working medium circulation pipe, characterized in that:

[0013] A micro-compression device is directly embedded in the condensation section of the heat pipe body;

[0014] A single-piece photovoltaic panel is welded to the outer surface of the condensation section, covering at least 50% of the area of the outer surface of the condensation section, and the inclination angle of the photovoltaic panel is 10° - 20°, for directly driving the micro-compressor;

[0015] The heat pipe body is also provided with a temperature sensor, which is arranged at the junction of the condensation section and the surface soil layer and is connected to the control module to dynamically start and stop the micro-compression device based on the temperature of the condensation section;

[0016] The working medium circulation pipe is connected to the micro-compressor, the evaporation section and the condensation section to form a closed-loop refrigeration cycle, in which the refrigerant is actively driven to circulate by the micro-compressor in the warm season, and the refrigerant is driven to circulate by the natural temperature difference in the cold season.

[0017] Preferably: the size of the photovoltaic panel is 1.5m × 0.6m, the power is 200W, the inclination angle is 15°, and the welding with the condensation section adopts a laser welding process to reduce the thermal resistance.

[0018] Preferably: the measurement accuracy of the temperature sensor is ±0.5°C, and it is connected to the cloud control platform through a wireless transmission module.

[0019] Preferably: the refrigerant in the working medium circulation pipe is R134a, its heat dissipation efficiency in the condensation section is ≥80%, and the system cold quantity transfer efficiency is increased by 40% compared with an external refrigerating machine.

[0020] Preferably: the evaporation section of the heat pipe body adopts a porous copper tube structure, and is covered with a nano-thermal insulation coating to reduce the thermal disturbance of external heat radiation to the frozen soil.

[0021] Preferably: the measurement accuracy of the temperature sensor is ±0.5°C, and it is connected to the cloud control platform through a wireless transmission module.

[0022] Preferably: the refrigeration power of the micro-compressor is 150W, it is internally provided with a capillary structure to optimize the refrigerant evaporation efficiency, and its working noise ≤45dB.

[0023] The present invention also discloses an application method using the above all-season refrigeration integrated heat pipe, characterized by including the following steps:

[0024] (1) Frozen soil investigation and heat demand analysis: Obtain the ice content and temperature field data of frozen soil through borehole sampling and distributed optical fiber sensing technology, and combine with the historical data of the meteorological station to collect the annual average temperature and the frequency of extreme high temperature;

[0025] (2) Selection of micro-compression device: Select a micro-compressor with a refrigeration power of 100 - 200W according to the calculation result of the frozen soil heat load. Its rated voltage is 24V, and R134a environmental protection refrigerant is used;

[0026] (3) Photovoltaic system design: Configure a single photovoltaic panel and energy storage battery. The power of the photovoltaic panel is 150 - 250W, meeting the power supply demand of 8 hours per day in the warm season;

[0027] (4) Heat pipe structure transformation: Embed the micro-compressor into the top of the condensation section of the heat pipe through flange connection and integrally weld it with the working medium circulation pipe;

[0028] (5) Temperature control logic setting: Set the trigger threshold of the temperature sensor to 0°C. When the temperature of the condensation section ≥ 0°C, start the compressor, and the system automatically shuts down at night without light;

[0029] (6) Dynamic regulation of cooling capacity: Based on the frozen soil temperature change rate and train load pressure data, dynamically adjust the operating frequency of the compressor through the PID algorithm;

[0030] (7) Engineering verification and monitoring: Deploy a subgrade deformation monitoring system to collect frozen soil settlement data in real time and feedback it to the control module.

[0031] Preferably: Dynamically regulate the cooling capacity according to the frozen soil temperature, which is divided into three working modes:

[0032] (1) When the permafrost ground temperature is greater than -1.0°C, adopt the photovoltaic + battery, one heat pipe with two micro-compressors, continuous working mode;

[0033] (2) When the permafrost ground temperature is between -2°C and -1.0°C, adopt the photovoltaic + battery, one heat pipe with one micro-compressor, intermittent working mode, start-stop ratio 11:1, daily working 22h;

[0034] (3) When the permafrost ground temperature is less than -2°C, adopt the photovoltaic direct drive micro-compressor mode, without battery participation, intermittent working mode.

[0035] Preferably: The train load pressure data described in step (6) is collected in real time through the strain gauge installed under the railway track, and the refrigeration power adjustment formula is: , where P0 is the basic power, ΔT is the change in frozen soil temperature, ΔL is the load change rate, and α and β are adjustment coefficients.

[0036] Preferably, the daily power generation of the photovoltaic system should meet the requirement: E_photovoltaic ≥ 1.2 × E_compressor.

[0037] Preferably, in step (7), the monitoring system adopts Beidou satellite positioning technology to monitor the roadbed settlement deviation in real time. The deviation threshold is set at ±5 mm, and when the limit is exceeded, a warning signal is triggered.

[0038] Beneficial effects

[0039] 1. Built-in micro-compression device: directly embedded in the condensation section of the thermosyphon, reducing heat conduction loss and improving the cold transfer efficiency.

[0040] 2. Photovoltaic direct drive: A single photovoltaic panel is integrated with the thermosyphon to achieve continuous power supply throughout the season, reducing external dependence. The working voltage of the micro-compressor is 24V, and only a single-sided photovoltaic panel is required to directly drive the compressor for refrigeration, without the need for an external power supply and an inverter control device, greatly saving the device cost. At the same time, the photovoltaic panel is welded to the condensation section of the thermosyphon, so that the condensation section cannot receive solar light, reducing the thermal disturbance of the permafrost in the evaporation section caused by the heat conduction of the thermosyphon body.

[0041] 3. Intelligent temperature control throughout the season: Based on the automatic start-stop logic of temperature sensing, dynamically matching the refrigeration demand. Description of the drawings

[0042] Figure 1 is a schematic diagram of the application structure of the all-season refrigeration integrated thermosyphon adopted by the present invention;

[0043] Figure 2 is a schematic diagram of the working principle of the thermosyphon. Detailed implementation manners

[0044] Example 1

[0045] The present invention discloses an all-season refrigeration integrated thermosyphon equipped with a photovoltaic direct drive micro-compression device, including a thermosyphon body, a working medium circulation connecting pipe, and a working medium circulation pipe, wherein:

[0046] The micro-compression device is directly embedded in the condensation section of the thermosyphon body; the thermosyphon body is a widely used existing technology, made of stainless steel. The whole thermosyphon is a stainless steel pipe, and the condensation section is provided with fins on the outside to facilitate heat dissipation in the cold season. The length of the condensation section is 2m and the diameter is 130mm. The diameter of the adiabatic section is 89 - 159mm, and the length can be 1 - 3m; the diameter of the evaporation section can be 89 - 159mm, and the length can be in the range of 5m - 15m.

[0047] See Figure 2 shown. The thermosyphon is a liquid-gas two-phase convective circulation heat transfer device, mainly including an evaporation section, an adiabatic section, and a condensation section, as Figure 1-2As shown. The evaporation section is in contact with the permafrost layer, and the condensation section is exposed to the air. When the temperature of the cold end section is lower than the permafrost temperature, the heat pipe starts to work. The liquid working medium in the evaporation section absorbs heat and evaporates into gas. Under the action of the pressure difference, the steam rises along the inner cavity of the pipe to the condensation section, contacts the relatively cold pipe wall, liquefies and releases heat, and condenses into liquid. Under the action of gravity, the liquid working medium flows back along the pipe wall to the evaporation section to absorb heat and evaporate again. In this way, the heat in the foundation is continuously sent into the atmosphere, thereby cooling the permafrost in the foundation and improving the thermal stability of the permafrost. A large number of heat pipes were used during the construction and operation of the Qinghai-Tibet Railway for permafrost protection, which is the most effective among the permafrost cooling protection measures.

[0048] The single-piece photovoltaic panel is welded to the outer surface of the condensation section, covering at least 80% of the outer surface area of the condensation section, and the inclination angle of the photovoltaic panel is 10° - 35°, which is used to directly drive the micro-compressor. An angle of 10 - 35 degrees mainly serves the purpose of shading. The photovoltaic panel faces south. The heat pipe is made of stainless steel, which can avoid the thermal disturbance of the underlying permafrost caused by material heat conduction and improve stability.

[0049] The heat pipe body is also provided with a temperature sensor, which is arranged at the junction of the condensation section and the surface soil layer and is connected to the control module to dynamically start and stop the micro-compression device based on the temperature of the condensation section;

[0050] The working medium circulation pipe connects the micro-compressor, the evaporation section and the condensation section to form a closed-loop refrigeration cycle. In the warm season, the refrigerant is actively driven by the micro-compressor to circulate, and in the cold season, the refrigerant is driven by the natural temperature difference to circulate. The inside of the condensation section is a hollow structure. The refrigeration copper pipe of the compressor is embedded in the condensation section in a spiral winding manner. The refrigeration copper pipe can be selected with a diameter of 5 - 10 mm and a length of 5 - 15 m is appropriate. See Figure 1 As shown.

[0051] The size of the photovoltaic panel is 1.5 m × 0.6 m, the power is 200 W, the inclination angle is 15°, and the welding with the condensation section adopts the laser welding process to reduce the thermal resistance.

[0052] The measurement accuracy of the temperature sensor is ±0.5 °C, and it is connected to the cloud control platform through a wireless transmission module.

[0053] The refrigerant in the working medium circulation pipe is R134a, its heat dissipation efficiency in the condensation section is ≥80%, and the system cold quantity transfer efficiency is increased by 40% compared with the external refrigeration machine.

[0054] The evaporation section of the heat pipe body adopts a porous copper pipe structure, covered with a nano-thermal insulation coating to reduce the thermal disturbance of external thermal radiation to the permafrost.

[0055] The measurement accuracy of the temperature sensor is ±0.5 °C, and it is connected to the cloud control platform through a wireless transmission module.

[0056] The refrigeration power of the micro-compressor is 150W, and it is built with a capillary structure to optimize the refrigerant evaporation efficiency, and its operating noise is ≤45dB.

[0057] Example 2

[0058] An application method of using the above all-season refrigeration integrated heat rod includes the following steps:

[0059] 1. Frozen soil investigation and heat demand analysis: Obtain the ice content and temperature field data of frozen soil through borehole sampling and distributed optical fiber sensing technology, and collect the annual average temperature, extreme high temperature frequency, sunshine duration, etc. in combination with the historical data of the meteorological station. Among them, the requirements for the ground temperature observation of permafrost in the investigation stage are as follows:

[0060] (1) The ground temperature observation of the frozen soil layer should include the temperature of each depth of the frozen soil layer and the change process over time and environment. According to the ground temperature observation results of the frozen soil, the characteristic parameters of the ground temperature of the frozen soil layer such as the seasonal freezing and thawing depth of the soil, the annual change depth of the frozen soil ground temperature, the annual average ground temperature of the frozen soil, and the lower limit of the frozen soil can be calculated.

[0061] (2) The ground temperature observation holes of the frozen soil layer should be set in typical natural environmental conditions and geomorphic units, or in natural sites within the monitoring area that are not affected by human and engineering disturbances.

[0062] (3) The depth of the ground temperature observation holes of the frozen soil layer should exceed 3m below the annual change depth of the ground temperature. As the observation depth of the regional control long-term monitoring hole, it is advisable to exceed 5m below the lower limit of permafrost. The depth of the observation hole is determined according to the characteristics of permafrost in the plateau or high-latitude regions, and should not be less than 16m.

[0063] (4) The observation holes should be drilled with a drill, and the final hole diameter should not be less than Φ90mm. A temperature measuring tube should be inserted into the hole, with a pipe diameter of Φ60mm, and the material should be aluminum-plastic pipe, ordinary steel pipe or stainless steel pipe. The bottom and joints of the temperature measuring tube should be sealed. The gap between the borehole wall and the temperature measuring tube should be backfilled with a mixture of sand and water with a particle size of 0.5mm - 2.0mm by vibration. When the temperature measuring hole is set, due to the heat during the drilling process, the frozen soil around the borehole melts, and the immediately observed ground temperature cannot represent the ground temperature of permafrost. Generally, it takes about 30 days for the ground temperature of the frozen soil to recover. Therefore, the temperature measuring holes should be constructed in advance.

[0064] (5) The ground temperature observation element should preferably use a thermistor or a platinum resistance temperature sensor, the observation temperature accuracy should be 0.05°C, and the measuring instrument should use a digital multimeter or data acquisition instrument with no less than 4 1 / 2 digits, and the output current should be less than 10μA. The ground temperature observation should be carried out after the frozen soil temperature state in the borehole is stable.

[0065] (6)The layout of ground temperature measurement points in permafrost should meet the following requirements: The observation depth should not be less than 1.0 m below the annual variation depth of ground temperature; The measurement points of temperature sensors should be arranged according to the engineering needs. Within the depth range of more than 5 m from the ground surface, they should be arranged at an interval of 0.5 m, and below 5 m, they should be arranged at an interval of 1.0 m.

[0066] (7)The ground temperature observation time in permafrost should meet the following requirements: Ground temperature observation can be carried out after the hole is formed. The annual average ground temperature should be based on the readings measured after the ground temperature has stabilized; For the ground temperature observation time, it should not be less than 3 times per month within half a year, and not less than 1 time per month from half a year to one year; For the long-term ground temperature observation holes over 3 years, the observation frequency should be set according to the engineering needs; The observation time for the maximum seasonal thaw depth should be from September to November, and the observation time for the maximum seasonal freezing depth should be from March to May.

[0067] (8)For the collation of ground temperature observation data in permafrost, it is advisable to use the horizontal coordinate as the ground temperature in permafrost and the vertical coordinate as the depth, and draw the distribution curve of the ground temperature in permafrost along the depth at different observation times. The depth value of the intersection point of the ground temperature curve and the vertical coordinate should be determined as the upper limit of permafrost for many years. In representative permafrost sections, ground temperature observation holes should be set. In principle, there should be no less than 1 per kilometer and no less than 2 per construction site; Long-term ground temperature observation holes should be set for major projects.

[0068] (9)Characteristic parameters such as the ground temperature gradient in permafrost for many years, the annual average ground temperature at the upper limit, the annual variation depth of ground temperature, and the annual average ground temperature can be calculated according to the provisions of GB50324 - 2014 "Code for Geological Investigation of Frozen Soil Engineering".

[0069] (10)Determination of the upper limit of permafrost for many years: The sounding method is to insert a steel bar into the soil, and judge the thawing depth at that time according to the principle that the thawed soil has a small hardness and the frozen soil has a large hardness. The description method is to judge the thawing depth at that time according to the characteristics that the thawed soil has a deep color, no ice crystals, and the frozen soil has a light color and contains ice crystals. The temperature measurement method is to measure the temperature with a thermometer at certain intervals, and then draw the curve of ground temperature changing with depth. The depth where the curve passes through the zero temperature axis is the thawing depth at that time.

[0070] According to the permafrost temperature, the dynamic regulation of cooling capacity is divided into three working modes:

[0071] (1)When the ground temperature of permafrost for many years is greater than -1.℃, use photovoltaic + battery (one thermosyphon with two micro compressors). Continuous working mode (continuous for 24 h);

[0072] (2)When the ground temperature of permafrost for many years is between -2℃ and -1.0℃, use photovoltaic + battery (one thermosyphon with one micro compressor). Intermittent working mode (start-stop ratio 11:1, daily working for 22 h);

[0073] (3)When the permafrost ground temperature is less than -2°C, the photovoltaic direct-drive micro-compressor mode (without battery) is adopted. Intermittent working mode (working during the day);

[0074] 2. Selection of micro-compression device: Select a micro-compressor with a refrigeration power of 100 - 200W according to the calculation result of the frozen soil heat load. Its rated voltage is 24V, and the environmentally friendly refrigerant R134a is used;

[0075] For a large-scale frozen soil area, a parallel control strategy of multiple micro-compressors is adopted, and the refrigeration tasks are dynamically allocated according to the regional heat load differences.

[0076] 3. Design of photovoltaic system: Configure a single photovoltaic panel and a storage battery. The power of the photovoltaic panel is 150 - 250W, and the capacity of the storage battery is 5 - 10kWh, meeting the power supply demand of 8 hours per day in the warm season; The storage battery is a lithium iron phosphate battery, and the charge and discharge efficiency is ≥95%. And the daily power generation of the photovoltaic system needs to meet: E_photovoltaic ≥ 1.2 × E_compressor. When the battery fails, the system can still work during the day, and when there is a battery, it is powered by the battery at night. Achieve 24-hour work throughout the day.

[0077] Integrated design of double-sided photovoltaic panel and reflector: Install a parabolic reflector on the back of the photovoltaic panel to increase the light absorption efficiency by 20% - 30%, and at the same time avoid the light on the condensation section (controlled by the reflector angle). Light-storage-cooling collaborative control: Energy storage scheduling strategy based on weather forecast, for example, pre-store electric energy before rainy weather to ensure continuous operation of the compressor.

[0078] 4. Modification of the thermosyphon structure: Embed the micro-compressor into the top of the condensation section of the thermosyphon through flange connection and integrally weld it with the working fluid circulation pipe;

[0079] Bionic fin design: The evaporation section adopts tree-root-shaped fractal fins to increase the contact area with the frozen soil and improve the cold transfer efficiency by more than 15%.

[0080] 5. Setting of temperature control logic: Set the trigger threshold of the temperature sensor to 5°C. When the temperature of the condensation section ≥ 5°C, start the compressor, and when the temperature ≤ 0°C, turn it off;

[0081] Combined with fuzzy logic (dealing with the non-linear thermal characteristics of frozen soil) and PID control (precise temperature adjustment), dynamically adjust the start-stop threshold of the compressor; Sensor data fusion: Integrate temperature, humidity, and wind speed sensors to build a multi-dimensional temperature control model. For example, automatically increase the refrigeration power by 10% in a high-humidity environment.

[0082] 6. Dynamic regulation of cold quantity: Based on the frozen soil temperature change rate and train load pressure data, dynamically adjust the operating frequency of the compressor through the PID algorithm; The train load pressure data is collected in real time by a strain gauge installed under the railway track. The refrigeration power adjustment formula is: , where P0 is the base power, ΔT is the change in permafrost temperature, ΔΔL is the load change rate, and α and β are adjustment coefficients.

[0083] 7. Engineering verification and monitoring: Deploy a subgrade deformation monitoring system to collect permafrost settlement data in real time and feed it back to the control module; the monitoring system uses Beidou satellite positioning technology to monitor the subgrade settlement deviation in real time, and the deviation threshold is set at ±5 mm. When the limit is exceeded, a warning signal is triggered. The permafrost deformation data and refrigeration efficiency data are uploaded to the blockchain to ensure the immutability of the monitoring results and provide a credible basis for technology promotion. When the subgrade settlement deviation > 5 mm is detected, the system automatically starts the micro-pile repair program and adjusts the refrigeration power to the maximum.

[0084] Workflow:

[0085] Warm season: The temperature sensor triggers the compressor to start, and the refrigerant circulates through the built-in pipeline to absorb heat, and the temperature of the condensation section drops below -5°C.

[0086] Cold season: The natural temperature difference drives the working fluid circulation mainly, and the compressor works during the day to obtain a lower temperature, which greatly improves the working efficiency of the heat pipe.

[0087] The present invention integrates a micro-compression device and a photovoltaic system to achieve active cooling of the heat pipe throughout the year; through an in-built structure design, the cold transfer efficiency is improved; a "refrigeration-energy storage-temperature control" integrated system is constructed to enhance the long-term stability of the subgrade.

[0088] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. An all-season refrigeration integrated heat pipe equipped with a photovoltaic direct-drive micro-compression device, comprising a heat pipe body, a working fluid circulation connecting pipe, and a working fluid circulation pipe, characterized in that: A micro-compression device is directly embedded in the condensation section of the heat pipe body; The photovoltaic panel is welded to the outer surface of the condensation section, covering at least 80% of the outer surface area of the condensation section, and the inclination angle of the photovoltaic panel is 10° - 20°, for directly driving the micro-compressor; The heat pipe body is also provided with a temperature sensor, arranged at the junction of the condensation section and the surface soil layer, and connected to the control module, to dynamically start and stop the micro-compression device based on the temperature of the condensation section; The working fluid circulation pipe connects the micro-compressor, the evaporation section, and the condensation section to form a closed-loop refrigeration cycle, where in the warm season, the refrigerant is circulated actively by the micro-compressor, and in the cold season, the refrigerant is circulated by the natural temperature difference.

2. The all-season refrigeration integrated heat pipe according to claim 1, wherein: The size of the photovoltaic panel is 1.5m × 0.6m, the power is 200W, the inclination angle is 15°, and the welding with the condensation section adopts the laser welding process; the photovoltaic panel is a double-sided photovoltaic panel, and a parabolic reflector is installed on the back of the photovoltaic panel.

3. The all-season refrigeration integrated heat pipe according to claim 1, characterized in that: The measurement accuracy of the temperature sensor is ±0.5°C, and it is connected to the cloud control platform through a wireless transmission module.

4. An application method of the all-season refrigeration integrated heat pipe described in claim 1, characterized in that It includes the following steps: (1) Frozen soil investigation and heat demand analysis: Obtain the ice content and temperature field data of the frozen soil through drilling sampling and distributed optical fiber sensing technology, and combine the historical data of the meteorological station to collect the annual average temperature and the frequency of extreme high temperatures; (2) Selection of micro-compression device: Select a micro-compressor with a refrigeration power of 100 - 200W according to the calculation result of the frozen soil heat load, its rated voltage is 24V, and the R134a environmental protection refrigerant is used; (3) Photovoltaic system design: Configure a single photovoltaic panel and an energy storage battery, and the power of the photovoltaic panel is 150 - 250W, to meet the power supply demand of 8 hours per day in the warm season; (4) Heat pipe structure transformation: Embed the micro-compressor into the top of the heat pipe condensation section through flange connection, and integrally weld it with the working fluid circulation pipe; (5) Temperature control logic setting: Set the trigger threshold of the temperature sensor to 0°C, start the compressor when the temperature of the condensation section ≥ 0°C, and the system automatically shuts down at night without light; (6) Dynamic regulation of cooling capacity: Based on the frozen soil temperature change rate and train load pressure data, dynamically adjust the operating frequency of the compressor through the PID algorithm; (7) Engineering verification and monitoring: Deploy a subgrade deformation monitoring system, and collect the frozen soil settlement data in real time and feedback it to the control module.

5. The application method according to claim 4, wherein: According to the frozen soil temperature, the dynamic regulation of cooling capacity is divided into three working modes: (1) When the permafrost ground temperature is greater than -1.0°C, adopt the photovoltaic + battery, one heat pipe with two micro-compressors, continuous working mode; (2) When the permafrost ground temperature is between -2°C and -1.0°C, adopt the photovoltaic + battery, one heat pipe with one micro-compressor, intermittent working mode, start-stop ratio 11:1, work 22h per day; (3) When the permafrost ground temperature is less than -2°C, adopt the photovoltaic direct-drive micro-compressor mode, without battery participation, intermittent working mode.

6. The application method according to claim 4, wherein: The step (5), Combining fuzzy logic and PID control, the compressor start and stop thresholds are dynamically adjusted; sensor data fusion: integrating temperature, humidity, and wind speed sensors to build a multi-dimensional temperature control model.

7. The application method according to claim 4, characterized in that: The daily power generation of the photovoltaic system must meet the following requirements: EPV ≥ 1.2 × Ecompressor.

8. The application method according to claim 4, characterized in that: The train load pressure data described in step (6) is collected in real time by strain gauges installed under the rails, and the refrigeration power adjustment formula is: , where P0 is the basic power, ΔT is the change in frozen soil temperature, ΔL is the load change rate, and α and β are adjustment coefficients.

9. The application method according to claim 4, wherein: The monitoring system described in step (7) uses Beidou satellite positioning technology to monitor the roadbed settlement deviation in real time. The deviation threshold is set to ±5mm, and an early warning signal is triggered when the limit is exceeded.

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