Temperature-adjustable miniature thermoelectric refrigeration system and temperature adjusting method thereof

Abstract

The invention relates to a thermoelectric refrigeration system, in particular to a temperature-adjustable micro thermoelectric refrigeration system and a temperature adjusting method thereof, and solves the technical problem that an existing portable or implantable thermoelectric refrigeration system is difficult to apply to a structure with limited size due to the fact that the existing portable or implantable thermoelectric refrigeration system is large in size and insufficient in temperature control precision or needs to be externally connected with a circulating pipeline. The thermoelectric refrigerating unit is integrated with the clamp type heat conduction copper sheet and the refrigerating probe, the overall size is extremely small, and the shape is suitable for being implanted and fixed in narrow biological spaces such as foramen intervertebrale; meanwhile, a control temperature adjusting module is integrated, complex thermal disturbance in biological tissue can be overcome, quick response and stable maintenance of the set temperature are achieved, and the temperature control precision is high. The invention solves the technical problem of stable and controllable cooling in a narrow biological space, and has a wide application prospect in the field of biomedicine.

Description

Technical Field

[0001] This invention relates to thermoelectric refrigeration systems, and more specifically to a temperature-adjustable micro thermoelectric refrigeration system and its temperature adjustment method. Background Technology

[0002] Thermoelectric coolers are based on the Peltier effect and have advantages such as no moving parts, no working medium, easy miniaturization, and precise temperature control. They are widely used in fields such as heat dissipation of electronic devices and temperature control of optical systems.

[0003] With the development of biomedical technology, there is an urgent need for localized, minimally invasive, and precise temperature control within organisms. For example, in fields such as neuroscience analgesia, there is a need for controllable cooling of specific tissues within extremely small spaces (such as the intervertebral foramen) to study their physiological functions. However, achieving this goal faces many technical challenges: First, commercially available thermoelectric coolers often fail to meet the requirements for miniaturization, biocompatibility, and specific shape factors necessary for implantation in organisms; second, the complex biothermal environment involving blood perfusion and tissue metabolic heat generation makes rapid, precise, and stable temperature control extremely difficult; and finally, there is a lack of integrated temperature control systems that can work in conjunction with in vivo micro-cooling devices.

[0004] Current portable or implantable thermoelectric cooling systems often suffer from problems such as large size, rigid structure, insufficient temperature control accuracy, or the need for external circulation pipelines, making them difficult to apply in size-constrained biological structures. Therefore, there is an urgent need for an integrated micro-thermoelectric cooling system that can meet the stringent requirements of implantation in biological systems and achieve high-performance, precise temperature control. Summary of the Invention

[0005] The purpose of this invention is to solve the technical problems of existing portable or implantable thermoelectric refrigeration systems being bulky, having insufficient temperature control accuracy, or requiring external circulation pipelines, making them difficult to apply in size-constrained structures. The invention provides an adjustable temperature micro thermoelectric refrigeration system and its temperature control method.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A temperature-adjustable micro thermoelectric cooling system for cooling biological tissues is characterized by comprising a micro thermoelectric cooling device, a temperature control module, and a fixation strap. The micro thermoelectric cooling device includes a thermoelectric cooler, a clip-type thermally conductive copper sheet, a columnar heat dissipation copper sheet, and a cooling probe; The hot side of the thermoelectric cooler is connected to the inner side of one end of a clip-type heat-conducting copper sheet, and the outer side of the clip-type heat-conducting copper sheet is connected to a columnar heat-dissipating copper sheet. The clip-type heat-conducting copper sheet is used to straddle the biological skeleton on both sides of the target biological tissue. The cold side of the thermoelectric cooler is connected to a cooling probe, the tip of which is exposed and used to closely adhere to the target biological tissue. A miniature thermocouple temperature probe is mounted on the tip and is used to detect the temperature of the target biological tissue in real time. The output end of the miniature thermocouple temperature probe is connected to the input end of the temperature control module via a temperature sensing wire. The output end of the temperature control module is connected to the power supply end of the thermoelectric cooler via a power supply wire. The temperature control module is used to supply power to the thermoelectric cooler and regulate its operating temperature. The temperature control module is mounted on a fixing strap, which is used to secure the temperature control module.

[0007] Furthermore, the thickness of the thermoelectric cooler is 1.6±0.1mm, the resistance is 2.4~2.6Ω, and the maximum temperature difference ΔTmax between the hot and cold surfaces of the thermoelectric cooler is 125℃.

[0008] Furthermore, the cooling probe has a diameter of 0.4 mm, a length of 2 mm, and a tip length of 0.2-0.4 mm.

[0009] Furthermore, the clip-type heat-conducting copper sheet adopts a U-shaped structure, with the inner side of one of the clamping arms connected to the hot surface of the thermoelectric cooler, and the outer side of the bottom of the U-shape connected to a columnar heat dissipation copper sheet. The clamping arm measures 5mm*6mm, the U-shaped bottom measures 5mm*8mm, and the thickness of both the clamping arm and the top is 0.3mm.

[0010] Furthermore, the temperature control module includes a temperature sensor, a microcontroller, a refrigeration drive circuit, and a human-machine interface; The input end of the temperature sensor is connected to the output end of the miniature thermocouple temperature probe via a temperature sensing wire, and the output end is connected to the input end of the microcontroller. The temperature sensor is used to work with the miniature thermocouple temperature probe to detect the temperature in real time. The output terminal of the microcontroller is connected to the control terminal of the refrigeration drive circuit, and is used to output corresponding control signals according to the signals from the temperature sensor. The output terminal of the refrigeration drive circuit is connected to the power supply terminal of the thermoelectric cooler through a power supply wire. It is used to control the input current of the thermoelectric cooler according to the control signal output by the microcontroller, thereby adjusting the working state of the thermoelectric cooler. The human-machine interface is interconnected with the microcontroller and is used to set the target temperature and view the current temperature information via a touch screen and / or remote communication.

[0011] Furthermore, the temperature control module's temperature adjustment process is as follows: A target temperature is set via a human-machine interface; the microcontroller receives the target temperature and simultaneously acquires current temperature information from a temperature sensor; the microcontroller calculates a control signal based on a preset control algorithm and outputs the control signal to the refrigeration drive circuit; the refrigeration drive circuit adjusts the input current of the thermoelectric cooler according to the control signal, changing its cooling capacity; the temperature sensor continuously monitors the temperature change of the refrigeration probe and feeds the signal back to the microcontroller; the microcontroller continuously adjusts the control signal based on the feedback signal and the target temperature until it reaches and maintains within the target temperature range.

[0012] The present invention also provides a temperature control method for the above-mentioned adjustable temperature micro thermoelectric refrigeration system, which is characterized by comprising the following steps: Step 1: Obtain the actual temperature using a miniature thermocouple temperature probe and send it to the temperature control module; Step 2: The temperature control module obtains the deviation between the actual temperature and the target temperature, and generates a control signal based on the temperature deviation using a control algorithm. Step 3: The temperature control module adjusts the input current of the thermoelectric cooler according to the control signal, thereby regulating its temperature; Step 4: Repeat steps 1-3 until the actual temperature reaches the target temperature, thus completing the temperature adjustment.

[0013] Furthermore, in step 2, the control algorithm is a PID control algorithm, and the specific method for generating the control signal through the control algorithm is as follows: Using the PID control algorithm, the control quantity is calculated using the following formula: u(t) = K p ×[e(t) + 1 / T i ×∫e(t)dt + T d [×de(t) / dt]; In the formula, u(t) represents the control quantity of the PID control algorithm at time t, and K p T is the proportionality coefficient. i Let T be the integration time constant. d Let e(t) be the differential time constant, e(t) be the feedback error, and t be the time.

[0014] Furthermore, in step 3, the specific method for adjusting the input current of the thermoelectric cooler is as follows: The load Q of the thermoelectric cooler c= 0 W, hot surface temperature Th = 85℃, under the ambient temperature, change the input current of the thermoelectric cooler, measure the temperature difference between the hot and cold surfaces of the thermoelectric cooler, obtain the temperature difference-input current relationship curve, fit it to obtain the input current adjustment calculation model, and then adjust the input current of the thermoelectric cooler according to the input current adjustment calculation model.

[0015] Furthermore, in step 3, the input current regulation calculation model is as follows: ΔT = 272.01×I - 238.53×I 2 +114.54×I 3 -26.51×I 4 +0.3; In the formula: I is the input current of the thermoelectric cooler, in A; ΔT is the temperature difference between the hot and cold surfaces of the thermoelectric cooler, in °C.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention provides a temperature-adjustable micro thermoelectric cooling system with high miniaturization and implantability: by integrating a thermoelectric cooler with a clip-type thermally conductive copper sheet and a micron-level cooling probe, a device with an extremely small overall size and a shape suitable for implantation and fixation in narrow biological spaces such as the intervertebral foramen is created.

[0017] 2. The present invention provides a temperature-adjustable micro thermoelectric refrigeration system with efficient heat dissipation and thermal management energy absorption: the clip-type structure can straddle both sides of biological tissue, which not only achieves mechanical fixation, but also provides a large heat dissipation area, ensuring efficient heat dissipation of the hot surface of the thermoelectric cooler, preventing thermal damage to surrounding tissues, and ensuring refrigeration efficiency.

[0018] 3. The present invention provides a temperature-adjustable micro thermoelectric refrigeration system with good biocompatibility and safety: the device design fully considers biocompatibility requirements, the tip of the refrigeration probe is precisely exposed, and the rest is insulated, so as to achieve effective refrigeration while minimizing the unintended impact on surrounding tissues.

[0019] 4. The present invention provides a temperature-adjustable micro thermoelectric refrigeration system with high system integration: it organically combines a micro thermoelectric refrigeration device and a temperature control module to form a complete, reliable and easy-to-operate integrated system.

[0020] 5. The present invention provides a temperature-adjustable micro thermoelectric refrigeration system with precise temperature control: the system integrates a temperature regulation module based on PID control algorithm, which can overcome complex thermal disturbances in biological tissues, achieve rapid response and stable maintenance of the set temperature, and has high temperature control accuracy. Attached Figure Description

[0021] Figure 1 This is a system structure diagram of an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the micro thermoelectric refrigeration device in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a thermoelectric cooler in an embodiment of the present invention, wherein (a) is the overall structure of the thermoelectric cooler, and (b) and (c) are schematic diagrams of the dimensions of the side and front of the thermoelectric cooler, respectively; Figure 4 This is a flowchart of the temperature control method according to an embodiment of the present invention; Figure 5 This is the temperature difference-input current relationship curve of the thermoelectric cooler in an embodiment of the present invention; Figure 6 Figure 1 is a schematic diagram of the application of the present invention for cooling, wherein A is a structural diagram of the micro thermoelectric cooling device, B is a schematic diagram of the micro thermoelectric cooling device being clamped and placed across both sides of the spine, C is a schematic diagram of the cooling probe passing through the intervertebral foramen and approaching the dorsal root ganglion, D is a schematic diagram of the cooling probe passing through the intervertebral foramen and approaching the dorsal root ganglion, and E is an overall schematic diagram of the micro thermoelectric cooling device being implanted into biological tissue. Figure 7 This is a flowchart illustrating the cooling process in an embodiment of the present invention. Figure 8 The following are cooling performance curves of the embodiments of the present invention at different power levels, wherein the power levels of (a), (b), and (c) are 0.124W, 0.176W, and 0.273W, respectively; The annotations in the attached figures are explained as follows: 1-Miniature thermoelectric cooling device, 2-Temperature control module, 3-Fixing strap, 4-Thermoelectric cooler, 5-Clip-type thermally conductive copper sheet, 6-Columnar heat dissipation copper sheet, 7-Cooling probe, 8-Miniature thermocouple temperature probe, 9-Temperature sensor, 10-Microcontroller, 11-Cooling drive circuit, 12-Human-machine interface. Detailed Implementation

[0022] The present invention provides a temperature-adjustable micro thermoelectric refrigeration system and its temperature control method in further detail below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0023] This embodiment provides an adjustable temperature micro thermoelectric refrigeration system, the core of which lies in achieving precise temperature regulation of local tissues within a living organism through miniaturization, integration, and intelligent control. For example... Figure 1As shown, a temperature-adjustable micro thermoelectric cooling system includes a micro thermoelectric cooling device 1, a temperature-adjustable micro thermoelectric cooling system control temperature regulation module 2, and a fixing strap 3. The micro thermoelectric cooling device 1 is implanted into biological tissue during use, the temperature-adjustable module 2 is located outside the biological tissue, and the fixing strap 3 is used to fix the temperature-adjustable module 2 in place.

[0024] like Figure 2 As shown, the miniature thermoelectric cooling device 1 includes a thermoelectric cooler 4, a clip-type heat-conducting copper plate 5, a columnar heat-dissipating copper plate 6, and a cooling probe 7. The hot side of the thermoelectric cooler 4 is connected to the inner side of one end of the clip-type heat-conducting copper plate 5, and the outer side of the clip-type heat-conducting copper plate 5 is connected to the columnar heat-dissipating copper plate 6. The clip-type heat-conducting copper plate 5 is used to straddle both sides of the biological skeleton at the target biological tissue. The cold side of the thermoelectric cooler 4 is connected to the cooling probe 7, and the tip of the cooling probe 7 is exposed to fit tightly against the target biological tissue. A miniature thermocouple temperature probe 8 is mounted on the tip, which is used to detect the temperature of the target biological tissue in real time.

[0025] The output of the miniature thermocouple temperature probe 8 is connected to the input of the temperature control module 2 via a temperature sensing wire. The output of the temperature control module 2 is connected to the power supply of the thermoelectric cooler 4 via a power supply wire. The temperature control module 2 is used to supply power to the thermoelectric cooler 4 and regulate its operating temperature. The temperature control module 2 is mounted on a fixing strap 3, which is used to fix the temperature control module 2.

[0026] The structure of thermoelectric cooler 4 is as follows Figure 3 As shown, it utilizes the Peltier effect. When current flows through a circuit containing two different conductors or semiconductors, a temperature change occurs near the junction. One junction absorbs heat, while the other releases heat, thus creating cooling. The thermoelectric cooler 4 has advantages such as small size, light weight, and low noise. In this embodiment, the thickness of the thermoelectric cooler 4 is 1.6±0.1mm, the resistance is 2.4~2.6Ω, and the maximum temperature difference ΔTmax between the hot and cold surfaces of the thermoelectric cooler 4 is 125℃, as shown in Table 1.

[0027] Table 1 In this embodiment, to achieve effective heat dissipation and a specific shape factor, the hot surface of the thermoelectric cooler 4 is connected to the inner side of a clip-type thermally conductive copper sheet using biocompatible thermally conductive adhesive. This clip-type structure can straddle both sides of a biological skeleton (such as the spine), achieving both mechanical fixation and providing a large heat dissipation area. A columnar heat-dissipating copper sheet is welded to the outer side of the clip-type copper sheet to further enhance heat dissipation. The clip-type thermally conductive copper sheet 5 adopts a U-shaped structure, with the inner side of one clamping arm connected to the hot surface of the thermoelectric cooler 4, and the outer side of the U-shaped bottom connected to the columnar heat-dissipating copper sheet 6. The clamping arm measures 5mm*6mm, the bottom of the U-shape measures 5mm*8mm, and the clip-type thermally conductive copper sheet 5 is an integrated structure formed by bending a single copper sheet with a thickness of 0.3mm. The cold side of the thermoelectric cooler 4 is connected to a cooling probe 7. The cooling probe 7 has a diameter of 0.4 mm, a length of 2 mm, and a tip length of 0.2-0.4 mm. It is made of a highly thermally conductive material, with the tip exposed to ensure cooling effect, while the rest is wrapped in a biocompatible insulating sleeve. A miniature thermocouple temperature probe 8 is integrated at the tip of the cooling probe 7 for real-time and direct measurement of the temperature at the cooling point.

[0028] Under actual operating conditions, heat exchange occurs between the refrigeration device, biological tissue, and the external environment. The total load Q of the refrigeration device... c These processes have had an impact. The heat exchange relationship between the thermoelectric cooler 4 and the biological tissue is as follows: ; In the formula: ρ t Density of biological tissues, unit: kg•m -3 ;c t Heat capacity of biological tissue, unit J•kg -1 •K -1 T is tissue temperature, in K; t is time, in seconds; k t Thermal conductivity of the structure, in W•m -1 •K -1 ;ω b Blood perfusion rate, unit: kg•m -3 •s -1 ;c b Blood specific heat, unit J•kg -1 •K -1 ;T a Arterial blood temperature, unit K; T v Q represents venous blood temperature, in Kelvin (K). met The unit for heat production from tissue metabolism is W•m. -3 Q s Heat exchanged between a thermoelectric cooler and biological tissue, measured in W·m³. -3 .

[0029] The heat exchange quantity Q between the thermoelectric cooler and the external environment h for: ; In the formula: Q h h is the heat exchange rate, in J; h is the convective heat transfer coefficient between the thermoelectric cooler and the environment, in W•m. -2 •K -1 A represents the heat exchange surface area between the thermoelectric cooler of the refrigeration device and the environment, in meters (m²). 2 ;T e Temperature of the thermoelectric cooler in the refrigeration device, in K; T k t represents ambient temperature in Kelvin (K); t represents time in seconds (s).

[0030] The temperature control module 2 includes a temperature sensor 9, a microcontroller 10, a refrigeration drive circuit 11, and a human-machine interface 12. The input terminal of the temperature sensor 9 is connected to the output terminal of a miniature thermocouple temperature probe 8 via a temperature sensing wire, and its output terminal is connected to the input terminal of the microcontroller 10. The temperature sensor 9 works in conjunction with the miniature thermocouple temperature probe 8 to detect temperature in real time. The temperature probe of the temperature sensor 9 is the miniature thermocouple temperature probe 8, which is fixed to the tip of the refrigeration probe 7. The miniature thermocouple temperature probe 8 is connected to the thermocouple circuit within the temperature sensor 9 via a temperature sensing wire. The output terminal of the microcontroller 10 is connected to the control terminal of the refrigeration drive circuit 11, and is used to output corresponding control signals based on the signals from the temperature sensor 9. The output terminal of the refrigeration drive circuit 11 is connected to the power supply terminal of the thermoelectric cooler 4 via a power supply wire, and is used to control the input current of the thermoelectric cooler 4 based on the control signals output by the microcontroller 10, thereby adjusting the operating state of the thermoelectric cooler 4. The human-machine interface 12 is interconnected with the microcontroller 10 and is used to set the target temperature and view the current temperature information via buttons, touch screen and / or remote communication.

[0031] The following is a simple explanation of the circuit principle of a refrigeration system that adjusts temperature via command: 1) Temperature sensor 9: A thermocouple circuit and temperature sensor used to measure the actual temperature of the refrigeration device.

[0032] 2) Microcontroller 10: Receives the signal from temperature sensor 9 and outputs the corresponding control signal according to the preset temperature range and control algorithm.

[0033] 3) Cooling drive circuit 11: According to the control signal output by the microcontroller 10, it controls the input current of the micro thermoelectric cooling device and adjusts the working state of the cooling device.

[0034] 4) Human-computer interaction interface 12: Users can set the target temperature and view the current temperature and other information through buttons, touch screen, remote communication and other means.

[0035] The temperature control process of the temperature regulation module 2 is as follows: the target temperature is set through the human-machine interface 12; the microcontroller 10 receives the target temperature and simultaneously obtains the current temperature information from the temperature sensor 9; the microcontroller 10 calculates the control signal according to the preset PID control algorithm and outputs the control signal to the refrigeration drive circuit 11; the refrigeration drive circuit 11 adjusts the input current of the thermoelectric cooler 4 according to the control signal to change its cooling capacity; the temperature sensor 9 continuously monitors the temperature change of the refrigeration probe 7 and feeds the signal back to the microcontroller 10; the microcontroller 10 continuously adjusts the control signal according to the feedback signal and the target temperature until it reaches and maintains within the target temperature range.

[0036] For example, if the current input current is 0.15A and the cold junction temperature is 28℃, and the user inputs a desired temperature of 26℃, the microcontroller 10 calculates the control signal through a PID control algorithm and adjusts the input current of the thermoelectric cooler 4 (assuming it is 0.2A). The cooling capacity of the thermoelectric cooler 4 increases, the temperature sensor 9 collects the temperature and compares it with the input desired temperature of 26℃. If there is a deviation, the deviation value is returned to the microcontroller 10. The above process is repeated until the measured cooling temperature value is within the range of the input desired temperature, thus achieving temperature control.

[0037] This embodiment also provides a temperature control method for the above-mentioned adjustable temperature micro thermoelectric refrigeration system, such as... Figure 4 As shown, it includes the following steps: Step 1: Use the miniature thermocouple temperature probe 8 to obtain the actual temperature and send it to the temperature control module 2.

[0038] Step 2: The temperature regulation module 2 acquires the deviation between the actual temperature and the target temperature, and generates a control signal based on the temperature deviation using a PID control algorithm. Specifically, the control quantity is calculated using the following formula: u(t) = K p ×[e(t) + 1 / T i ×∫e(t)dt + T d [×de(t) / dt]; In the formula, u(t) represents the control quantity of the PID control algorithm at time t, and K p T is the proportionality coefficient. i Let T be the integration time constant. d Let e(t) be the differential time constant, e(t) be the feedback error, and t be the time.

[0039] Step 3: The temperature control module 2 adjusts the current input to the thermoelectric cooler 4 according to the control signal, thereby regulating its temperature. Under the load Q of the thermoelectric cooler 4... c= 0 W, hot surface temperature Th = 85℃, operating ambient temperature, such as room temperature of approximately 22℃, change the input current of thermoelectric cooler 4, measure the temperature difference between its hot and cold surfaces, and obtain the following results: Figure 5 The temperature difference-input current relationship curve shown is used to obtain the input current adjustment calculation model as shown in the following formula through fitting. Then, the input current of thermoelectric cooler 4 is adjusted accordingly: ΔT = 272.01×I - 238.53×I 2 +114.54×I 3 -26.51×I 4 +0.3; In the formula: I is the input current of thermoelectric cooler 4, in A; ΔT is the temperature difference between the hot end and the cold end of thermoelectric cooler 4, in °C.

[0040] To verify the cooling performance of this embodiment, a temperature control test was conducted by implanting it at a specific location in a mouse, including: System implantation: such as Figure 6 As shown, a miniature thermoelectric cooling device is implanted near the target tissue, a clip-shaped copper plate is fixed to the bone, the tip of the cooling probe is in close contact with the target tissue, and a wire is led through a subcutaneous tunnel to the head for fixation. The working principle is as follows: Figure 7 As shown.

[0041] Performance testing: Under ideal operating ambient temperature, such as room temperature of about 22°C, different electrical powers (0.124W, 0.176W, 0.273W) were applied to the adjustable temperature micro thermoelectric cooling system provided in this embodiment, and the temperature of the cooling probe tip (representing the biological tissue cooling temperature) and the temperature of the heat sink copper plate (representing the hot end temperature) were recorded simultaneously.

[0042] Test results are as follows Figure 8 As shown, the results demonstrate that this embodiment can rapidly cool the target tissue to a set temperature (e.g., below 25°C) with extremely low power consumption, while maintaining the hot end temperature within a safe range (below 40°C). This fully demonstrates the system's ability to perform efficient, safe, and precise local cooling within a living organism.

Claims

1. A thermoelectric micro-refrigeration system for biological tissue cooling, characterized in that: It includes a micro thermoelectric cooling device (1), a temperature control module (2), and a fixing strap (3); The micro thermoelectric cooling device (1) includes a thermoelectric cooler (4), a clip-type heat-conducting copper sheet (5), a columnar heat-dissipating copper sheet (6), and a cooling probe (7). The hot side of the thermoelectric cooler (4) is connected to the inner side of one end of the clip-type heat-conducting copper sheet (5), and the outer side of the clip-type heat-conducting copper sheet (5) is connected to the columnar heat-dissipating copper sheet (6). The clip-type heat-conducting copper sheet (5) is used to straddle the biological skeleton on both sides of the target biological tissue. The cold side of the thermoelectric cooler (4) is connected to the cooling probe (7). The tip of the cooling probe (7) is exposed and used to closely adhere to the target biological tissue. The tip is equipped with a miniature thermocouple temperature probe (8). The miniature thermocouple temperature probe (8) is used to detect the temperature of the target biological tissue in real time. The output end of the miniature thermocouple temperature probe (8) is connected to the input end of the temperature control module (2) through a temperature sensing line. The output end of the temperature control module (2) is connected to the power supply end of the thermoelectric cooler (4) through a power supply wire. The temperature control module (2) is used to supply power to the thermoelectric cooler (4) and adjust its working temperature. The temperature control module (2) is mounted on the fixing strap (3), which is used to fix the temperature control module (2).

2. A thermoelectric micro-refrigeration system according to claim 1, wherein: The thickness of the thermoelectric cooler (4) is 1.6±0.1mm, the resistance is 2.4~2.6Ω, and the maximum temperature difference ΔTmax between the hot and cold surfaces of the thermoelectric cooler (4) is 125℃.

3. A thermoelectric micro-refrigeration system according to claim 2, wherein: The cooling probe (7) has a diameter of 0.4 mm and a length of 2 mm.

4. A thermoelectric micro-refrigeration system according to claim 3, wherein: The clamp-type heat-conducting copper sheet (5) adopts a U-shaped structure, with the inner side of one of the clamping arms connected to the hot surface of the thermoelectric cooler (4), and the outer side of the bottom of the U-shape connected to the columnar heat dissipation copper sheet (6). The clamping arm measures 5mm*6mm, the U-shaped bottom measures 5mm*8mm, and the thickness of both the clamping arm and the top is 0.3mm.

5. A miniature thermoelectric cooling system according to any one of claims 1 to 4, wherein: The temperature control module (2) includes a temperature sensor (9), a microcontroller (10), a refrigeration drive circuit (11), and a human-machine interface (12). The input end of the temperature sensor (9) is connected to the output end of the miniature thermocouple temperature probe (8) through a temperature sensing line, and the output end is connected to the input end of the microcontroller (10). The temperature sensor (9) is used to cooperate with the miniature thermocouple temperature probe (8) to detect the temperature in real time. The output terminal of the microcontroller (10) is connected to the control terminal of the refrigeration drive circuit (11) and is used to output corresponding control signals according to the signal of the temperature sensor (9); The output terminal of the refrigeration drive circuit (11) is connected to the power supply terminal of the thermoelectric cooler (4) through a power supply wire. It is used to control the input current of the thermoelectric cooler (4) according to the control signal output by the microcontroller (10), thereby adjusting the working state of the thermoelectric cooler (4). The human-machine interface (12) is interconnected with the microcontroller (10) and is used to set the target temperature and view the current temperature information through a touch screen and / or remote communication.

6. A thermoelectric micro-refrigeration system according to claim 5, wherein The temperature control module (2) performs the following temperature adjustment process: the target temperature is set through the human-machine interface (12); the microcontroller (10) receives the target temperature and obtains the current temperature information from the temperature sensor (9); the microcontroller (10) calculates the control signal according to the preset PID control algorithm and outputs the control signal to the refrigeration drive circuit (11); the refrigeration drive circuit (11) adjusts the input current of the thermoelectric cooler (4) according to the control signal to change its cooling capacity; the temperature sensor (9) continuously monitors the temperature change of the refrigeration probe (7) and feeds the signal back to the microcontroller (10); the microcontroller (10) continuously adjusts the control signal according to the feedback signal and the target temperature until it reaches and is maintained within the target temperature range.

7. A method of temperature adjustment of a micro thermoelectric refrigeration system according to any one of claims 1 to 6, wherein Includes the following steps: Step 1: Use a miniature thermocouple temperature probe (8) to obtain the actual temperature in real time and send it to the temperature control module (2). Step 2: The temperature control module (2) obtains the deviation between the actual temperature and the target temperature, and generates a control signal based on the temperature deviation through the control algorithm; Step 3: The temperature control module (2) adjusts the input current of the thermoelectric cooler (4) according to the control signal, thereby adjusting its temperature; Step 4: Repeat steps 1-3 until the actual temperature reaches the target temperature, thus completing the temperature adjustment.

8. The method of claim 7, wherein the temperature of the micro-thermoelectric cooling system is adjusted by varying the current supplied to the micro-thermoelectric cooling system. In step 2, the control algorithm is a PID control algorithm, and the specific method for generating the control signal through the control algorithm is as follows: Using the PID control algorithm, the control quantity is calculated using the following formula: u(t) = K p ×[e(t) + 1 / T i ×∫e(t)dt + T d ×de(t) / dt] where u(t) represents the control amount of the PID control algorithm at time t, K p is a proportional coefficient, T i is an integral time constant, T d is a differential time constant, e(t) is a feedback error, and t is time.

9. The temperature adjustment method of a thermoelectric micro-refrigeration system according to claim 7 or 8, wherein, In step 3, the specific method for adjusting the input current of the thermoelectric cooler (4) is as follows: In the heat-electricity refrigerator (4), the load Q c = 0 W, the hot surface temperature Th = 85℃, under the temperature of the using environment, the input current of the heat-electricity refrigerator (4) is changed, the temperature difference between the hot surface and the cold surface of the heat-electricity refrigerator (4) is measured, the temperature difference-input current relation curve is obtained, the input current adjustment calculation model is obtained by fitting, and then the input current of the heat-electricity refrigerator (4) is adjusted according to the input current adjustment calculation model.

10. The temperature control method of a temperature-adjustable micro thermoelectric refrigeration system according to claim 9, characterized in that, In step 3, the input current regulation calculation model is as follows: ΔT = 272.01 x I - 238.53 x I 2 + 114.54 x I 3 - 26.51 x I 4 + 0.3; In the formula: I is the input current of the thermoelectric cooler (4), in A; ΔT is the temperature difference between the hot and cold surfaces of the thermoelectric cooler (4), in °C.

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