Cooling device for coal mine electromechanical equipment and cooling method thereof

Abstract

The invention discloses a cooling device for coal mine electromechanical equipment and a cooling method thereof, relates to the technical field of heat dissipation and temperature control of the coal mine electromechanical equipment, and can solve the problems of low heat dissipation efficiency, poor reliability and difficulty in maintenance of the electromechanical equipment under complex working conditions of high dust, high humidity, strong vibration and the like of an underground coal mine in the prior art. The cooling device comprises a cooling main machine arranged in the stable roadway far away from the mining working face and a cooling pipeline connected to the cooling main machine; the cooling pipeline comprises a main pipe laid along a roadway and a plurality of branch pipes communicated with the main pipe and connected in parallel, the branch pipes are attached to the outer surfaces of heating components of the coal mine electromechanical equipment respectively, and a cooling medium circularly flows in the cooling pipeline so as to exchange heat of the heating components and convey the heat into the cooling host; the two ends of the main pipe are connected to a circulating heat exchange assembly of the cooling host. The circulating heat exchange assembly is used for driving the cooling medium to circularly flow and exchange heat with the outside for cooling.

Description

Technical Field

[0001] This application relates to the technical field of heat dissipation and temperature control of coal mine electromechanical equipment, specifically to a cooling device and cooling method for coal mine electromechanical equipment. Background Technology

[0002] There are many types of electromechanical equipment in coal mines. Equipment located near the mining face and adjacent roadways includes coal mining machines, face scraper conveyors, transfer conveyors and crusher drive systems, roadway belt conveyors, emulsion pump stations, etc. These devices generally have characteristics such as high power density, large load fluctuations, frequent start-ups and shutdowns, and some devices need to move with the advancement of the working face. The working face and adjacent roadways near the mining face may experience a combination of conditions including high concentrations of coal dust, methane gas presence and emission, washing water / dripping water and mine water infiltration, fluctuating temperature, humidity and ventilation conditions, narrow spaces and restricted passageways, and impacts and vibrations caused by mining and vehicle operation. Simultaneously, impacts from falling coal / gangue, support movement and compression, and scraping of transport equipment occur frequently. To meet explosion-proof safety requirements, electrical control equipment often uses thick-walled explosion-proof enclosures and limited lead / ventilation channels, with the enclosure surface frequently covered in dust and contaminated by water mist / slurry. Some equipment needs to be moved or repositioned as the working face advances, resulting in frequent bending, dragging, and collisions of external cables and pipelines, and relatively limited space and time for on-site maintenance.

[0003] Due to the aforementioned environmental and structural constraints, existing heat dissipation methods for electromechanical equipment present varying degrees of failure risks and maintenance burdens: Firstly, solutions relying on natural heat dissipation from the outer casing or external heat sinks are limited by the high thermal resistance of the explosion-proof casing, dust accumulation on the outer surface, and small heat dissipation margin; secondly, forced air cooling within cabinets, air-to-air heat exchangers, or small cabinet air conditioners are prone to efficiency degradation due to dust clogging of fins / filters and difficulties in condensate management. Fan lifespan is shortened by vibration and dust, and maintenance of the refrigeration system after seal aging is costly and unreliable under underground conditions; thirdly, compressed air refrigeration methods such as vortex tubes have low energy efficiency and require high air dryness, posing a risk of condensation / icing; fourthly, exposed heat exchangers, pumps, valves, and joints are easily damaged by falling coal, vehicle movement, or support structure movement. In summary, existing technologies struggle to simultaneously achieve both heat dissipation efficiency and operational reliability in complex underground environments, and further improvements are still possible. Summary of the Invention

[0004] Therefore, this application provides a cooling device and cooling method for electromechanical equipment in coal mines, in order to solve the problems of low heat dissipation efficiency, poor reliability and difficult maintenance of electromechanical equipment under complex working conditions such as high dust, high humidity and strong vibration in underground coal mines.

[0005] To achieve the above objectives, this application provides the following technical solution: A cooling device for electromechanical equipment in a coal mine includes a cooling host arranged in a stable roadway away from the mining face and a cooling pipeline connected to the cooling host. The cooling pipeline includes a main pipe laid along the roadway and multiple branch pipes connected to and in parallel with the main pipe. The multiple branch pipes are respectively attached to the outer surface of the heating components of multiple coal mine electromechanical equipment. The cooling medium circulates in the cooling pipeline to exchange and transport the heat of the heating components to the cooling host. The two ends of the main pipe are respectively connected to the circulating heat exchange component of the cooling host. The circulating heat exchange component is used to drive the cooling medium to circulate and exchange heat with the outside environment for cooling.

[0006] Optionally, the cooling pipeline includes an outer tube and an inner tube coaxially disposed inside and spaced apart from the outer tube. An annular gap is formed between the outer tube and the inner tube. A support member is provided between the outer tube and the inner tube to maintain the predetermined geometric dimensions of the annular gap and the coaxiality of the outer tube and the inner tube. The cooling medium includes a first fluid flowing through the annular gap and a second fluid flowing through the inner tube, wherein the flow rate of the second fluid is greater than that of the first fluid.

[0007] Optionally, the cooling host includes a housing, two distributors arranged inside the housing, a first pump, a first cooler, a second pump, a second cooler, and a controller arranged inside the housing; Both ends of the cooling pipeline are connected to the two flow dividers, and a first cooling branch and a second cooling branch are connected between the two flow dividers. The first pump body and the first cooler are connected in series in the first cooling branch, and the second pump body and the second cooler are connected in series in the second cooling branch. One flow divider, in conjunction with the first pump body and the second pump body, is used to guide the first fluid and the second fluid in the cooling pipeline into the first cooling branch and the second cooling branch, respectively. After being cooled, the first fluid and the second fluid are collected by another flow divider and circulated back into the cooling pipeline. The first cooler and the second cooler are used to exchange heat with an external cold source to reduce the temperature of the first fluid and the second fluid flowing through them, respectively. The controller is electrically connected to the first pump body, the second pump body, and the actuator used to adjust the heat exchange conditions of the first cooler and the second cooler.

[0008] Optionally, the distributor includes a box body connected to the inner wall of the housing and a first cavity formed in the box body. The box body has a first channel communicating with the first cavity and for connecting the outer tube. The box body has a second channel communicating with the first cavity and for connecting the first cooling branch. The cavity wall of the first cavity is integrally formed with a drain pipe extending to the first channel and for connecting with the inner tube. The drain pipe is clearance-fitted with the first channel. The end of the drain pipe near the first channel forms a third channel penetrating to the outer wall of the box body. The third channel is used to connect with the second cooling branch. The housing body has a mating hole that mates with the first channel.

[0009] Optionally, the first channel has a first annular step formed near the outer wall of the box to cooperate with the outer tube, and the third channel has a second annular step formed near one end of the first channel to cooperate with the inner tube. A first annular electromagnetic component is installed at the first annular step for magnetic attraction of the first magnetic annular component at the end of the outer tube, and a second annular electromagnetic component is installed at the second annular step for magnetic attraction of the second magnetic annular component at the end of the inner tube.

[0010] Optionally, the first cooler includes a first finned heat exchanger connected to the first cooling branch, and the actuating component of the first cooler is a first fan connected to the housing and used to cooperate with the first finned heat exchanger; the second cooler includes a second finned heat exchanger connected to the second cooling branch, and the actuating component of the second cooler is a second fan connected to the housing and used to cooperate with the second finned heat exchanger; the first fan and the second fan are electrically connected to the controller.

[0011] Optionally, the support is a flexible spiral heat-conducting rib. The flexible spiral heat-conducting rib extends continuously along the axial direction of the cooling pipeline in a spiral shape around the outer periphery of the inner tube and is wound with a preset pitch. Its inner edge abuts against the outer wall of the inner tube and its outer edge abuts against the inner wall of the outer tube, so as to maintain a predetermined size of the annular gap between the outer tube and the inner tube in a continuously axially supported manner.

[0012] Optionally, a fluorescent tracer is added to the first fluid, and an explosion-proof fluorescent leak detection module is arranged at intervals along the axial direction on the outer wall of the cooling pipeline. The fluorescent leak detection module includes an excitation unit for emitting ultraviolet excitation light and a photosensitive unit for receiving fluorescence and outputting an electrical signal, so as to identify the fluorescent tracer and generate a leak alarm signal when the first fluid leaks from the cooling pipeline.

[0013] This application also discloses a cooling method for a cooling device, which categorizes multiple coal mine electromechanical equipment into high-temperature source equipment, medium-temperature source equipment, and low-temperature source equipment according to the intensity of the heat source. The cooling method includes: Step 1: Through thermal severity calculation, the temperature range of coal mine electromechanical equipment is unified to [0,1]: , The measured temperature of device j This is the starting point for temperature control of device j. The upper limit of the allowable temperature for device j. The thermal severity of device j; Step 2, calculate the effective weight of device j. And overall cooling requirements U: , in, As a weighting system, high-temperature source equipment is assigned a weight of 1.0, medium-temperature source equipment is assigned a weight of 0.6, and low-temperature source equipment is assigned a weight of 0.3. This is an environmental correction factor; Thermal severity of various coal mine electromechanical equipment By effective weight By performing a weighted summation, we obtain the system-level comprehensive cooling requirement U: , ; Step 3: Convert the overall cooling demand U into target operating parameters for the first pump body, the second pump body, the first fan, and the second fan: First pump body: , in, The target rotational speed of the first pump body; , These are the minimum and maximum permissible speeds of the first pump body, respectively. This is the proportionality coefficient; To meet comprehensive cooling requirements The proportion of followers; For environmental feedforward; This is a pressure upper limit constraint device, which detects that the operating pressure of the outer pipe reaches or exceeds the set maximum allowable pressure. At this time, the controller automatically lowers the pump speed command of the first pump body to ensure that the system operating pressure does not exceed the safe upper limit; Among them, environmental severity for: , in, The actual ambient temperature measured in the underground tunnel. As the control benchmark for ambient temperature, The highest permissible ambient temperature, The function restricts the result to between 0 and 1; Second pump body: , , in, The target rotational speed of the second pump body; , These are the minimum and maximum permissible speeds of the second pump body, respectively. As the proportionality coefficient, Linear mapping to The work area; When the overall cooling demand When the value is zero, it indicates that the thermal severity of all equipment is within a safe range, and the second pump body maintains its operating status at the minimum setpoint allowed by the system. To ensure basic circulation and pipeline stability; when the overall cooling demand... Reaching the maximum sum of the severity levels of all heavy equipment When this occurs, it indicates that the entire system is under the highest heat load condition, and at this time, the operating status of the second pump body rises to the maximum allowable set value. To achieve maximum heat dissipation capacity; Fan: , in, The target rotational speed of the first fan / second fan; This refers to the minimum rotational speed of the first fan / second fan; To map the temperature difference signal between the first and second coolers to a proportional factor for the fan speed increment; The logarithmic average temperature difference between the first and second coolers.

[0014] Optionally, the flow distribution of the cooling medium among the branch pipes: , For the first The nominal flow share of each branch; The effective weight of the equipment in this branch pipe; The thermal severity of the equipment in this branch pipe; This is the minimum opening coefficient; The traffic share of each branch is the greater of the two; , For the first The target percentage for each branch; This is the sum of the nominal shares of all branches.

[0015] Compared with the prior art, this application has at least the following beneficial effects: The cooling host drives the cooling medium to form a closed loop in the main pipe and multiple branch pipes through the circulating heat exchange components. After flowing into the main pipe, the cooling medium is transported along the roadway and enters the corresponding coal mine electromechanical equipment through each parallel branch pipe. The pipe wall of each branch pipe can be in close contact with the outer surface of the heat-generating parts of the equipment. The heat generated during the operation of the equipment is conducted to the flowing cooling medium. After absorbing the heat, the temperature of the cooling medium rises and then returns to the cooling host along the main pipe to enter the circulating heat exchange components, where it exchanges heat with the outside air or cooling medium, releases the absorbed heat, and cools down again. Through continuous circulation, heat is continuously transported from high-heat-source equipment underground to stable roadways far from the mining face. The stable roadway environment is relatively constant, with good ventilation, low dust concentration, and minimal humidity and temperature fluctuations. Furthermore, it is far from the impact, vibration, and coal erosion of the mining face, effectively reducing the effects of dust abrasion, water vapor corrosion, and vibration fatigue on the equipment. This achieves a thermal management process of localized heat extraction and distant heat exchange. The parallel layout of main and branch pipes allows multiple coal mine electromechanical equipment to be connected to the same cooling system simultaneously, saving layout space and improving energy efficiency. The close-fitting arrangement of branch pipes results in a short heat dissipation path and low thermal resistance, enabling rapid heat removal from heat-generating components and preventing performance degradation or insulation aging caused by localized overheating. Attached Figure Description

[0016] To more intuitively illustrate the prior art and this application, several exemplary figures are provided below. It should be understood that the specific shapes and structures shown in the figures should not generally be regarded as limiting conditions for implementing this application; for example, based on the technical concept disclosed in this application and the exemplary figures, those skilled in the art are able to easily make conventional adjustments or further optimizations to the addition / reduction / classification, specific shapes, positional relationships, connection methods, size ratios, etc. of certain units (components).

[0017] Figure 1 A schematic diagram of the overall structure of a cooling device for coal mine electromechanical equipment provided in one embodiment of this application; Figure 2 This is a schematic diagram of the cooling pipeline of a cooling device for coal mine electromechanical equipment, provided in one embodiment of this application. Figure 3 for Figure 2 Partial structural diagram; Figure 4 A schematic diagram of the structure of a cooling host for a cooling device for coal mine electromechanical equipment, provided in one embodiment of this application; Figure 5 This application provides a schematic diagram of the structure of a circulating heat exchange component for a cooling device used in coal mine electromechanical equipment, as one embodiment of the present application. Figure 6 for Figure 4 Partial structural diagram; Figure 7 A schematic diagram of the structure of a flow divider for a cooling device for coal mine electromechanical equipment, provided in one embodiment of this application; Figure 8 for Figure 7 Sectional view at point aa; Figure 9 for Figure 8 Enlarged view of point A in the middle.

[0018] Explanation of reference numerals in the attached figures: 1. Cooling main unit; 11. Diverter; 111. Mating hole; 112. First cavity; 113. Drain pipe; 1131. Second annular step; 114. First channel; 1141. First annular step; 115. Second channel; 116. Third channel; 12. First cooling branch; 121. First pump body; 122. First cooler; 1221. First finned heat exchanger; 1222. First fan; 13. Second cooling branch; 131. Second pump body; 132. Second cooler; 1321. Second finned heat exchanger; 1322. Second fan; 10. Circulating heat exchange assembly; 2. Cooling pipeline; 21. Main pipe; 22. Branch pipe; 23. Outer pipe; 231. Annular gap; 24. Inner pipe; 25. Support component; 3. Coal mine electromechanical equipment. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0020] In the description of this application: unless otherwise stated, "a plurality of" means two or more. The terms "first," "second," "third," etc., in this application are intended to distinguish the objects referred to and do not have any special meaning in terms of technical connotation (e.g., they should not be construed as an emphasis on importance or order). Expressions such as "including," "comprising," and "having" also mean "not limited to" (certain units, components, materials, steps, etc.).

[0021] refer to Figure 1 This application discloses a cooling device for coal mine electromechanical equipment 3, including a cooling host 1 arranged in a stable roadway far from the mining face and a cooling pipeline 2 connected to the cooling host 1. The cooling pipeline 2 includes a main pipe 21 laid along the roadway and multiple branch pipes 22 connected to the main pipe 21 and in parallel with each other. The multiple branch pipes 22 are respectively attached to the outer surface of the heating components of multiple coal mine electromechanical equipment 3. The cooling medium circulates in the cooling pipeline 2 to exchange and transport the heat of the heating components to the cooling host 1. The two ends of the main pipe 21 are respectively connected to the circulating heat exchange component 10 of the cooling host 1. The circulating heat exchange component 10 is used to drive the cooling medium to circulate and exchange heat with the outside world to cool down.

[0022] The cooling host 1 drives the cooling medium to form a closed loop in the main pipe 21 and multiple branch pipes 22 through the circulating heat exchange component 10. After flowing into the main pipe 21, the cooling medium is transported along the roadway direction and enters the corresponding coal mine electromechanical equipment 3 through each parallel branch pipe 22. The pipe wall of each branch pipe 22 can be in close contact with the outer surface of the heat-generating component of the equipment. The heat generated during the operation of the equipment is conducted to the flowing cooling medium. After absorbing the heat, the temperature of the cooling medium rises and then returns to the cooling host 1 along the main pipe 21 to enter the circulating heat exchange component 10, where it exchanges heat with the outside air or cooling medium, releases the absorbed heat, and cools down again. Through continuous circulation, heat is continuously transported from high-heat-source equipment underground to stable roadways far from the mining face. The stable roadway (generally the main underground roadway) has a relatively constant environment with good ventilation, low dust concentration, and minimal humidity and temperature fluctuations. Furthermore, it is far from the impact, vibration, and coal erosion of the mining face, effectively reducing the effects of dust abrasion, water vapor corrosion, and vibration fatigue on the equipment. This achieves a thermal management process of local heat extraction and remote heat exchange. The parallel layout of the main pipe 21 and branch pipes 22 allows multiple coal mine electromechanical equipment 3 to be connected to the same cooling system simultaneously, saving layout space and improving energy efficiency. The close-fitting arrangement of the branch pipes 22 results in a short heat dissipation path and low thermal resistance, enabling rapid heat removal from heat-generating components and preventing performance degradation or insulation aging caused by localized overheating.

[0023] It should be noted that the coal mine electromechanical equipment 3 includes, but is not limited to: coal mining machine and its frequency conversion drive unit, working face scraper conveyor, transfer conveyor and crusher drive system, roadway belt conveyor, emulsion pump station, support electro-hydraulic control console, central substation power distribution equipment, communication and monitoring control box, video surveillance system and other electrical control cabinets or hydraulic drive equipment that require heat dissipation.

[0024] The branch pipe 22 can be arranged to be attached to the heating element by winding or coiling, or it can be attached to a plane or curved surface of the heating element by S-shaped coiling. Specifically, the branch pipe 22 can be connected to the heating element by adhesive, fixing structure (such as clamp, C-clamp, etc.). In some embodiments, since most of the coal mine electromechanical equipment 3 near the working face will move with the mining of the working face, both the branch pipe 22 and the main pipe 21 can be equipped with electric winches so that the branch pipe 22 and the main pipe 21 can be wound up and down with the mining of the working face.

[0025] In some embodiments, multiple branch pipes 22 are connected between two main pipes 21. The main pipes 21 and the branch pipes 22 can be connected by a multi-way valve, which can regulate the flow rate of the multiple branch pipes 22.

[0026] The cooling pipe 2 includes an outer pipe 23 and an inner pipe 24 coaxially disposed inside the outer pipe 23 and spaced apart from it. An annular gap 231 is formed between the outer pipe 23 and the inner pipe 24. A support member 25 is provided between the outer pipe 23 and the inner pipe 24 to maintain the predetermined geometric dimensions of the annular gap 231 and the coaxiality of the outer pipe 23 and the inner pipe 24. The cooling medium includes a first fluid flowing through the annular gap 231 and a second fluid flowing through the inner tube 24, with the flow rate of the second fluid being greater than that of the first fluid.

[0027] refer to Figure 2-3 The outer tube 23 and the inner tube 24 are arranged coaxially and maintained by a fixed gap through the support member 25. The cooling host 1 drives the first fluid and the second fluid to circulate in the annular gap 231 and the inner tube 24 respectively, forming a dual-loop heat exchange system. The support member 25 plays a role in spacing and support in structure. It can effectively prevent the inner tube 24 from being significantly eccentric or sticking to the wall when the pipeline is bent, compressed or vibrated, and ensure that the annular gap 231 maintains the predetermined geometric dimensions and fluid flow channel stability along its entire length, thereby ensuring uniform flow field distribution and constant heat transfer area.

[0028] The second fluid in the inner tube 24 has a higher flow velocity, enabling it to quickly remove heat and maintain a large heat exchange temperature difference when flowing through the heat-generating components of various electromechanical devices, achieving rapid heat absorption and efficient heat dissipation. Meanwhile, the first fluid flowing through the annular gap 231 has a relatively lower flow velocity, forming a temperature gradient buffer layer on the outer surface. This reduces structural stress caused by the temperature difference between the inner and outer tubes and prevents fatigue damage caused by localized condensation, expansion, or vibration on the surface of the outer tube 23. Through the differentiated design of the inner and outer fluid flow velocities and the geometric constraint of the support component 25, the entire dual-tube structure maintains flexible installation capabilities while also ensuring thermal conductivity, vibration resistance, and long-term operational reliability.

[0029] In some embodiments, the first fluid and the second fluid may be solutions with good thermal conductivity, low freezing point and corrosion resistance, such as aqueous solutions of ethylene glycol, aqueous solutions of propylene glycol, or composite coolants containing corrosion inhibitors, antibacterial agents and defoamers.

[0030] refer to Figure 4-9 The cooling host 1 includes a box, two distributors 11 arranged inside the box, a first pump body 121, a first cooler 122, a second pump body 131, a second cooler 132, and a controller arranged inside the box. The two ends of the cooling pipe 2 are connected to two distributors 11 respectively. A first cooling branch 12 and a second cooling branch 13 are connected between the two distributors 11. A first pump body 121 and a first cooler 122 are connected in series in the first cooling branch 12. A second pump body 131 and a second cooler 132 are connected in series in the second cooling branch 13. One distributor 11, together with the first pump body 121 and the second pump body 131, is used to guide the first fluid and the second fluid in the cooling pipe 2 into the first cooling branch 12 and the second cooling branch 13 respectively. After being cooled, the first fluid and the second fluid are collected by another distributor 11 and circulated into the cooling pipe 2. The first cooler 122 and the second cooler 132 are used to exchange heat with the external cold source to reduce the temperature of the first fluid and the second fluid respectively. The controller is electrically connected to the first pump body 121, the second pump body 131 and the actuator used to adjust the heat exchange conditions of the first cooler 122 and the second cooler 132.

[0031] The first pump body 121 and the second pump body 131 provide flow rate and head for the first cooling branch 12 and the second cooling branch 13, respectively. A distributor 11 directs the first and second fluids from the cooling pipe 2 into their respective branches according to their medium affiliation, allowing the two fluids to circulate independently in their respective branches without cross-flow. The first cooler 122 and the second cooler 132 in the two branches exchange heat with the external cold source, promptly removing the heat carried by their respective fluids. The low-temperature fluids after heat exchange are collected by another distributor 11 and returned to the cooling pipe 2, forming a continuous and stable circulating heat dissipation channel. This arrangement clearly separates the two loops structurally and allows them to operate in parallel functionally, reducing the decrease in heat exchange efficiency and the risk of backheating along the flow path caused by mixed flow, while also facilitating independent adjustment of the two branches for different operating conditions. The controller is electrically connected to the actuators of the two pump bodies and coolers, and can coordinate the pumping and heat exchange intensity according to the operating conditions, thereby achieving higher heat exchange efficiency and more stable heat dissipation.

[0032] The distributor 11 includes a box connected to the inner wall of the housing and a first cavity 112 formed in the box. The box has a first channel 114 that communicates with the first cavity 112 and is used to connect the outer tube 23. The box has a second channel 115 that communicates with the first cavity 112 and is used to connect the first cooling branch 12. The cavity wall of the first cavity 112 is integrally formed with a drain pipe 113 that extends to the first channel 114 and is used to connect with the inner tube 24. The drain pipe 113 is clearance-fitted with the first channel 114. The end of the drain pipe 113 near the first channel 114 forms a third channel 116 that penetrates to the outer wall of the box. The third channel 116 is used to connect with the second cooling branch 13. The housing has a mating hole 111 that mates with the first channel 114, so that the cooling pipe 2 can be connected to the distributor 11 through the mating hole 111.

[0033] When the cooling unit 1 is running, the first fluid (within the annular gap 231) and the second fluid (within the inner tube 24) from the cooling pipe 2 enter the casing of the distributor 11 through different channels. The first cavity 112 inside the casing is used to contain and guide the first fluid. The first channel 114 introduces the first fluid into the first cavity 112, while the second channel 115 guides the first fluid to the corresponding first cooling branch 12. Simultaneously, the guide pipe 113 is coaxially arranged within the first channel 114, serving as an independent flow channel for the second fluid. One end of the guide pipe is connected to the inner tube 24, and the other end is connected to the second cooling branch 13 through the third channel 116, guiding the second fluid into the second cooling branch 13. The fluid power for both the first and second fluids is provided by the first pump body 121 and the second pump body 131. Through this flow-dividing structure, the first and second fluids can achieve independent circulation within a limited space, avoiding mixing and improving the stability of the fluid transport and heat exchange process.

[0034] The first channel 114 has a first annular step 1141 formed near the outer wall of the box to engage with the outer tube 23. The third channel 116 has a second annular step 1131 formed near one end of the first channel 114 to engage with the inner tube 24. A first annular electromagnetic component is installed at the first annular step 1141 for magnetic engagement with the first magnetic annular component at the end of the outer tube 23. A second annular electromagnetic component is installed at the second annular step 1131 for magnetic engagement with the second magnetic annular component at the end of the inner tube 24.

[0035] When the distributor 11 is connected to the cooling pipe 2, the first annular electromagnetic component, after being energized, generates a circumferential magnetic field at the opening of the first channel 114. This field applies radial self-guiding and axial attraction to the first magnetic annular component at the end of the outer tube 23, causing the end face of the outer tube 23 to be pulled and pressed against the first annular step 1141 for positioning and clamping. Simultaneously, the second annular electromagnetic component located at the end of the third channel 116 near the first channel 114 generates a coaxial attraction effect on the second magnetic annular component at the end of the inner tube 24, guiding the end of the inner tube 24 to the second annular step 1131 and achieving axial contact. The two sets of electromagnetic attraction use the step as a thrust and radial limiting reference, which can automatically correct minor eccentricity and tilting errors during the connection process, thereby achieving synchronous, coaxial, and rapid connection of the outer tube 23 and the inner tube 24 at the same interface position.

[0036] It reduces assembly errors and time costs caused by manual alignment and tightening, forms a stable axial preload to improve the reliability of vibration and shock resistance connection, and enables quick disassembly and assembly by power-off unlocking when maintenance or replacement is required.

[0037] In some embodiments, the first magnetic ring component, the first ring electromagnetic component, the second magnetic ring component, and the second ring electromagnetic component can all be wrapped with rubber layers at their corresponding positions. On the one hand, the rubber layer can effectively isolate the metal components from the erosion of humid air, coal dust, and corrosive mine water, prevent the metal components from rusting or the insulation performance of the electromagnetic components from decreasing, and extend the service life of the magnetic structure. On the other hand, the rubber layer can form a flexible sealing interface when it is electrically attracted, improving the airtightness and waterproof performance between the electromagnetic components and the tube end, while also buffering the micro-vibrations and impacts at the magnetic joint.

[0038] The first cooler 122 includes a first finned heat exchanger 1221 connected to the first cooling branch 12. The actuating component of the first cooler 122 is a first fan 1222 connected to the housing and used to cooperate with the first finned heat exchanger 1221. The second cooler 132 includes a second finned heat exchanger 1321 connected to the second cooling branch 13. The actuating component of the second cooler 132 is a second fan 1322 connected to the housing and used to cooperate with the second finned heat exchanger 1321. The first fan 1222 and the second fan 1322 are electrically connected to the controller.

[0039] When the cooling system is working, the first pump body 121 and the second pump body 131 drive the first fluid and the second fluid to flow through the corresponding first cooler 122 and second cooler 132, respectively. When the first fluid flows through the pipes of the first finned heat exchanger 1221, it conducts heat with the metal wall between the fins. After the first fan 1222 starts running, it forms a through-flow airflow, causing the air to pass through the fins at high speed, thereby enhancing the convective heat transfer process of the air to the surface of the heat exchanger. Similarly, the second fluid in the second finned heat exchanger 1321 exchanges heat through the inner wall and is forced to remove heat by the second fan 1322. By coordinating and adjusting the speed and operating status of the two fans through the controller, heat exchange can be achieved on demand according to changes in the fluid temperature, flow rate, and heat load of each branch.

[0040] The support is a flexible spiral heat-conducting rib. The flexible spiral heat-conducting rib extends continuously along the axial direction of the cooling pipe 2 in a spiral shape around the outer periphery of the inner tube 24 and is wound with a preset pitch. Its inner edge abuts against the outer wall of the inner tube 24 and its outer edge abuts against the inner wall of the outer tube 23, so as to maintain the predetermined size of the annular gap 231 between the outer tube 23 and the inner tube 24 in a continuous axial support.

[0041] The flexible spiral heat-conducting ribs serve both structural support and heat conduction / flow guidance functions during operation. Extending spirally around the outer circumference of the inner tube 24 with a preset pitch, they absorb external forces through elastic deformation when the cooling pipe 2 is subjected to bending, vibration, or pressure changes, limiting the inner tube 24's offset relative to the outer tube 23 or its contact with the wall, ensuring continuous and unobstructed flow of the first fluid. Simultaneously, the spiral arrangement of the flexible spiral heat-conducting ribs generates a certain circumferential component and turbulence effect within the annular gap 231, breaking the laminar boundary layer, enhancing convective heat transfer, and preventing uneven temperature distribution or localized stagnation along the flow path.

[0042] A fluorescent tracer is added to the first fluid. Explosion-proof fluorescent leakage detection modules are arranged at intervals along the axial direction on the outer wall of the cooling pipe 2. The fluorescent leakage detection module includes an excitation unit for emitting ultraviolet excitation light and a photosensitive unit for receiving fluorescence and outputting electrical signals, so as to identify the fluorescent tracer and generate a leakage alarm signal when the first fluid leaks from the cooling pipe 2.

[0043] When the system is operating normally, the first fluid circulates within the closed cooling pipe 2, with the fluorescent tracer uniformly dispersed within it, preventing contact with the external environment. Explosion-proof fluorescent leak detection modules are spaced axially along the cooling pipe 2, and their excitation units periodically emit ultraviolet light of a specific wavelength towards the pipe wall. When leakage or micro-cracks occur in the pipe, the first fluid containing the fluorescent tracer seeps to the pipe wall surface. Under ultraviolet excitation light, the fluorescent tracer emits a characteristic fluorescent signal, which is received in real time by adjacent photosensitive units and converted into an electrical signal. After signal processing, the controller identifies this as a leak event and triggers an alarm or shutdown command. This operating method enables non-contact, real-time online monitoring in the early stages of leakage, avoiding losses of cooling fluid or moisture damage to electrical equipment caused by delays in manual inspections.

[0044] This application also discloses a cooling method for a cooling device, which, in order to adapt to the differences in heat load, heat flux density and operating conditions of different equipment in the working face and its adjacent roadways, divides multiple coal mine electromechanical equipment into high-temperature source equipment, medium-temperature source equipment and low-temperature source equipment according to the strength of the heat source. High-temperature source equipment is typically characterized by dense power electronic devices, high heat flux density, and significant load steps, such as traction / cutting frequency converters for coal mining machines, drive frequency converters for scraper conveyor heads, and drive and braking units for crushers / transfer conveyors. Medium-temperature source equipment mainly consists of electrical sets and electromagnetic components with continuous heat dissipation and moderate fluctuation, such as frequency converters for belt conveyor drives / tensioning sections, busbars and contacts of power supply switch cabinets, reactors and small transformers, etc. Low-temperature source equipment mainly consists of devices with low or intermittent heat dissipation requirements, such as sensor / communication boxes, electronic components of bracket electro-hydraulic control consoles, and other auxiliary devices.

[0045] The purpose of the above-mentioned classification is to provide a unified priority and weight basis for subsequent temperature control and flow allocation, so that the controller can prioritize the peak heat dissipation capacity of high-temperature sources under the same resource constraints, maintain steady-state temperature rise for medium-temperature sources, and prevent overcooling and condensation risks for low-temperature sources. This enables on-demand cooling, improves system energy efficiency and reliability, and provides clear parameterized boundaries for setting temperature target ranges, alarm thresholds and pre-cooling trigger strategies for various types of equipment. The classification can be determined before commissioning based on design and test data, or it can be adaptively fine-tuned during operation based on heat load statistics and environmental correction coefficients within a certain time window to maintain long-term matching with field conditions.

[0046] Specifically, the controller classifies the equipment into "high temperature source / medium temperature source / low temperature source" and assigns weights, calculates the severity of heat based on real-time temperature (or branch temperature difference), and then synthesizes it into a comprehensive cooling demand. Based on this, it generates the speed / power of the cooling system consisting of two pumps and two fans in the cooling host. At the same time, it introduces environmental feedforward and dew point protection, external loop pressure limiting and branch allocation to achieve stable and efficient collaborative control.

[0047] Cooling methods include: Step 1: Through thermal severity calculation (normalized temperature deviation), the temperature range of coal mine electromechanical equipment is unified to [0,1]: , The measured temperature of device j This is the starting point for temperature control of device j. The upper limit of the allowable temperature for device j. Let J be the thermal severity of device j (a dimensionless number from 0 to 1). Among them, when , This indicates that the actual measured temperature of the equipment is still below the set "control starting point" and is within the safe range. The cooling system can maintain minimum power operation and does not require additional accelerated cooling. when , A value of 1 indicates that the measured temperature of the equipment has reached its maximum permissible limit. Exceeding this limit could trigger over-temperature protection, cause damage, or pose a safety risk, requiring the cooling system to operate at full capacity.

[0048] Step 2, calculate the effective weight of device j. And overall cooling requirements U: , in, As a weighting system, high-temperature source equipment is assigned a weight of 1.0, medium-temperature source equipment is assigned a weight of 0.6, and low-temperature source equipment is assigned a weight of 0.3. The environmental correction factor (poor ventilation / heavy dust / limited maintenance, etc., preferably 1.0-1.3); Thermal severity of various coal mine electromechanical equipment By effective weight By performing weighted summation, the system-level comprehensive cooling demand U is obtained. This indicator can quantitatively reflect the overall heat load and provide a unified control basis for the power distribution of pumps and fans. , , Step 3: Convert the overall cooling demand U into target operating parameters (speed / power commands) for the first pump body, the second pump body, the first fan, and the second fan, thus establishing a quantitative correspondence between the cooling load and the corresponding execution unit's operating state. First pump body: , in, The target rotational speed of the first pump body; , These are the minimum and maximum permissible speeds of the first pump body, respectively. This is the proportionality coefficient; To meet comprehensive cooling requirements The following ratio (preferably 0.3-0.7) is used to determine the extent to which the first pump body of the outer pipe follows the overall cooling demand U for adjustment; To provide environmental feedforward, the operating power of the first pump body is appropriately increased when the thermal environment is harsh or the dew point is close, and cooling is enhanced in advance in harsh environments. This is a pressure upper limit constraint device, which detects that the operating pressure of the outer pipe reaches or exceeds the set maximum allowable pressure. At this time, the controller automatically lowers the pump speed command of the first pump body to ensure that the system operating pressure does not exceed the safe upper limit; Among them, environmental severity for: , in, The actual ambient temperature measured in the underground tunnel. As the control benchmark for ambient temperature, The highest permissible ambient temperature, The function restricts the result to between 0 and 1; When the underground ambient temperature rises and exceeds the set upper limit, Senv will gradually increase, indicating that the environment is becoming increasingly harsh. This value will be sent to the controller to determine whether the first pump and the first blower need to increase their workload in advance. Second pump body: , , in, The target rotational speed of the second pump body; , These are the minimum and maximum permissible speeds of the second pump body, respectively. As the proportionality coefficient, Linear mapping to The work area; When the overall cooling demand When the value is zero, it indicates that the thermal severity of all equipment is within a safe range, and the second pump body maintains its operating status at the minimum setpoint allowed by the system. To ensure basic circulation and pipeline stability; when the overall cooling demand... Reaching the maximum sum of the severity levels of all heavy equipment When this occurs, it indicates that the entire system is under the highest heat load condition, and at this time, the operating status of the second pump body rises to the maximum allowable set value. To achieve maximum heat dissipation capacity; Fan: , in, The target rotational speed of the first fan / second fan; This refers to the minimum rotational speed of the first fan / second fan; To map the temperature difference signal between the first and second coolers to a proportional factor for the fan speed increment; The logarithmic mean temperature difference between the first cooler and the second cooler; When the temperature difference (LMTD) between the first and second coolers increases, it indicates an increase in cooling demand; the formula will be increased accordingly. This means that as the fan speed increases, convective heat transfer on the air side is enhanced. When the temperature difference decreases, the formula automatically reduces the fan speed to save energy.

[0049] Flow distribution of cooling medium among the branch pipes: , For the first The nominal flow share of each branch; The effective weight of the equipment in this branch pipe; The thermal severity of the equipment in this branch pipe; The minimum opening coefficient is typically 10–15%, ensuring that even with a very low equipment load, the flow will not be completely interrupted, thus avoiding air resistance or liquid stagnation. The flow share for each branch is the greater of two values—either the result of weight multiplied by severity, or the minimum opening. This ensures that the system can respond to equipment thermal loads without completely shutting down any branch. , For the first The target percentage for each branch; The sum of the nominal shares of all branches is used for normalization to ensure that the total allocation ratio of all branches equals 1.

[0050] A relative proportion is calculated based on the heat demand and minimum opening of all branch pipes, and the flow is then distributed to each branch proportionally. In a parallel system, the cooling flow allocation for each branch depends not only on the thermal severity and weight of the equipment but also on ensuring a minimum flow threshold to prevent branch pipe flow interruption. Through normalization, the target flow proportions of all branches are summed to 1, and the valve opening of each branch is controlled according to these proportions, thereby achieving a rational allocation of cooling resources among different equipment.

[0051] The technical features of the above embodiments can be combined in any way (as long as there is no contradiction in the combination of these technical features). For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; these embodiments not explicitly written should also be considered to be within the scope of this specification.

[0052] The present application has been described in a relatively specific and detailed manner above through general descriptions and specific embodiments. It should be understood that, based on the technical concept of the present application, several conventional adjustments or further innovations can be made to these specific embodiments; however, as long as they do not depart from the technical concept of the present application, the technical solutions obtained by these conventional adjustments or further innovations also fall within the protection scope of the claims of the present application.

Claims

1. A cooling device for electromechanical equipment in coal mines, characterized in that, Includes a cooling host located in a stable roadway far from the mining face and cooling pipelines connected to the cooling host; The cooling pipeline includes a main pipe laid along the roadway and multiple branch pipes connected to and in parallel with the main pipe. The multiple branch pipes are respectively attached to the outer surface of the heating components of multiple coal mine electromechanical equipment. The cooling medium circulates in the cooling pipeline to exchange and transport the heat of the heating components to the cooling host. The two ends of the main pipe are respectively connected to the circulating heat exchange component of the cooling host. The circulating heat exchange component is used to drive the cooling medium to circulate and exchange heat with the outside environment for cooling.

2. The cooling device according to claim 1, characterized in that, The cooling pipeline includes an outer tube and an inner tube coaxially disposed inside the outer tube and spaced apart from it. An annular gap is formed between the outer tube and the inner tube. A support is provided between the outer tube and the inner tube to maintain the predetermined geometric dimensions of the annular gap and the coaxiality of the outer tube and the inner tube. The cooling medium includes a first fluid flowing through the annular gap and a second fluid flowing through the inner tube, wherein the flow rate of the second fluid is greater than that of the first fluid.

3. The cooling device according to claim 2, characterized in that, The cooling host includes a housing, two distributors arranged inside the housing, a first pump body, a first cooler, a second pump body, a second cooler, and a controller, all arranged inside the housing. Both ends of the cooling pipeline are connected to the two flow dividers, and a first cooling branch and a second cooling branch are connected between the two flow dividers. The first pump body and the first cooler are connected in series in the first cooling branch, and the second pump body and the second cooler are connected in series in the second cooling branch. One flow divider, in conjunction with the first pump body and the second pump body, is used to guide the first fluid and the second fluid in the cooling pipeline into the first cooling branch and the second cooling branch, respectively. After being cooled, the first fluid and the second fluid are collected by another flow divider and circulated back into the cooling pipeline. The first cooler and the second cooler are used to exchange heat with an external cold source to reduce the temperature of the first fluid and the second fluid flowing through them, respectively. The controller is electrically connected to the first pump body, the second pump body, and the actuator used to adjust the heat exchange conditions of the first cooler and the second cooler.

4. The cooling device according to claim 3, characterized in that, The distributor includes a box body connected to the inner wall of the housing and a first cavity formed in the box body. The box body has a first channel communicating with the first cavity and for connecting the outer tube. The box body has a second channel communicating with the first cavity and for connecting the first cooling branch. The cavity wall of the first cavity is integrally formed with a drain pipe that extends to the first channel and is used to connect with the inner tube. The drain pipe is clearance-fitted with the first channel. The end of the drain pipe near the first channel forms a third channel that penetrates to the outer wall of the box body. The third channel is used to connect with the second cooling branch. The box body has a mating hole that mates with the first channel.

5. The cooling device according to claim 4, characterized in that, The first channel has a first annular step formed near the outer wall of the box to cooperate with the outer tube, and the third channel has a second annular step formed near one end of the first channel to cooperate with the inner tube. A first annular electromagnetic component is installed at the first annular step for magnetic attraction of the first magnetic annular component at the end of the outer tube. A second annular electromagnetic component is installed at the second annular step for magnetic attraction of the second magnetic annular component at the end of the inner tube.

6. The cooling device according to claim 3, characterized in that, The first cooler includes a first finned heat exchanger connected to the first cooling branch, and the actuating component of the first cooler is a first fan connected to the housing and used to cooperate with the first finned heat exchanger. The second cooler includes a second finned heat exchanger connected to the second cooling branch, and the actuating component of the second cooler is a second fan connected to the housing and used to cooperate with the second finned heat exchanger. The first fan and the second fan are electrically connected to the controller.

7. The cooling device according to claim 2, characterized in that, The support is a flexible spiral heat-conducting rib. The flexible spiral heat-conducting rib extends continuously along the axial direction of the cooling pipeline in a spiral shape around the outer periphery of the inner tube and is wound with a preset pitch. Its inner edge abuts against the outer wall of the inner tube and its outer edge abuts against the inner wall of the outer tube, so as to maintain the predetermined size of the annular gap between the outer tube and the inner tube in a continuous axial support.

8. The cooling device according to claim 2, characterized in that, A fluorescent tracer is added to the first fluid. An explosion-proof fluorescent leak detection module is arranged at intervals along the axial direction on the outer wall of the cooling pipeline. The fluorescent leak detection module includes an excitation unit for emitting ultraviolet excitation light and a photosensitive unit for receiving fluorescence and outputting an electrical signal, so as to identify the fluorescent tracer and generate a leak alarm signal when the first fluid leaks from the cooling pipeline.

9. A cooling method for a cooling device, characterized in that, Multiple coal mine electromechanical equipment are classified into high-temperature source equipment, medium-temperature source equipment, and low-temperature source equipment according to the intensity of the heat source. Cooling methods include: Step 1: Through thermal severity calculation, the temperature range of coal mine electromechanical equipment is unified to [0,1]: ， The measured temperature of device j This is the starting point for temperature control of device j. The upper limit of the allowable temperature for device j. The thermal severity of device j; Step 2, calculate the effective weight of device j. And overall cooling requirements U: ， in, As a weighting system, high-temperature source equipment is assigned a weight of 1.0, medium-temperature source equipment is assigned a weight of 0.6, and low-temperature source equipment is assigned a weight of 0.

3. This is an environmental correction factor; Thermal severity of various coal mine electromechanical equipment By effective weight By performing a weighted summation, we obtain the system-level comprehensive cooling requirement U: ， ， Step 3: Convert the overall cooling demand U into target operating parameters for the first pump body, the second pump body, the first fan, and the second fan: First pump body: ， in, The target rotational speed of the first pump body; , These are the minimum and maximum permissible speeds of the first pump body, respectively. This is the proportionality coefficient; To meet comprehensive cooling requirements The proportion of followers; For environmental feedforward; This is a pressure upper limit constraint device, which detects that the operating pressure of the outer pipe reaches or exceeds the set maximum allowable pressure. At this time, the controller automatically lowers the pump speed command of the first pump body to ensure that the system operating pressure does not exceed the safe upper limit; Among them, environmental severity for: ， in, The actual ambient temperature measured in the underground tunnel. As the control benchmark for ambient temperature, The highest permissible ambient temperature, The function restricts the result to between 0 and 1; Second pump body: ， ， in, The target rotational speed of the second pump body; , These are the minimum and maximum permissible speeds of the second pump body, respectively. As the proportionality coefficient, Linear mapping to The work area; When the overall cooling demand When the value is zero, it indicates that the thermal severity of all equipment is within a safe range, and the second pump body maintains its operating status at the minimum setpoint allowed by the system. To ensure basic circulation and pipeline stability; when the overall cooling demand... Reaching the maximum sum of the severity levels of all heavy equipment When this occurs, it indicates that the entire system is under the highest heat load condition, and at this time, the operating status of the second pump body rises to the maximum allowable set value. To achieve maximum heat dissipation capacity; Fan: ， in, The target rotational speed of the first fan / second fan; This refers to the minimum rotational speed of the first fan / second fan; To map the temperature difference signal between the first and second coolers to a proportional factor for the fan speed increment; The logarithmic average temperature difference between the first and second coolers.

10. The cooling method according to claim 9, characterized in that, Flow distribution of cooling medium among the branch pipes: ， For the first The nominal flow share of each branch; The effective weight of the equipment in this branch pipe; The thermal severity of the equipment in this branch pipe; This is the minimum opening coefficient; The traffic share of each branch is the greater of the two; ， For the first The target percentage for each branch; It is the sum of the nominal shares of all branches.

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