Two-way temperature control system of temperature-sensitive element

Abstract

The invention discloses a two-way temperature control system of a temperature-sensitive element. The two-way temperature control system comprises an acquisition module, a control module and a temperature driving module, the acquisition module acquires the temperature of the temperature-sensitive element and outputs high-sensitivity temperature information and low-sensitivity temperature information; the control module controls the temperature of the temperature-sensitive element to a first precision of a target temperature according to the real-time low-sensitivity temperature information, and then controls the temperature of the temperature-sensitive element to a second precision of the target temperature according to the real-time high-sensitivity temperature information; wherein the first precision is lower than the second precision; the acquisition module comprises an adjustable resistor. The temperature control range is adjusted through the adjustable resistor, so that wide-range temperature control is achieved, meanwhile, the control precision is improved through double-channel temperature collection and double-precision temperature control, the working environment and performance of the temperature-sensitive element are remarkably improved, and it is ensured that the temperature-sensitive element can stably and reliably operate in a high-precision application scene.

Description

Technical Field

[0001] The present application relates to temperature control, and more specifically, to a dual-path temperature control system of a temperature-sensitive element. Background Art

[0002] The temperature measurement strategy based on thermistors has been developed for decades. In order to improve the temperature measurement accuracy of thermistors and make them operate stably and reliably in various application scenarios, people have developed many different methods to control the temperature stability of thermistors, such as the two-wire method, the four-wire method (Kelvin method), the balanced DC bridge and the unbalanced AC bridge. The two-wire method has been replaced by the four-wire method in some high-precision measurements due to accuracy issues. However, in the prior art, the temperature control method based on thermistors cannot simultaneously meet the requirements of a wide temperature control range and high-precision control. Summary of the invention

[0003] The present application provides a dual-channel temperature control system for a temperature-sensitive element, which adjusts the temperature control range through adjustable resistors to achieve wide-range temperature control, and at the same time improves the control accuracy through dual-channel temperature acquisition and dual-precision temperature control. As a result, the working environment and performance of the temperature-sensitive element are significantly improved, ensuring that it can operate stably and reliably in high-precision application scenarios.

[0004] The present application provides a dual-path temperature control system for a temperature-sensitive element, including an acquisition module, a control module, and a temperature driving module;

[0005] The acquisition module acquires the temperature of the temperature-sensitive element and outputs high-sensitivity temperature information and low-sensitivity temperature information;

[0006] The control module controls the temperature driving module to perform low-sensitivity temperature adjustment according to the real-time low-sensitivity temperature information. After the temperature of the temperature-sensitive element is controlled to a first accuracy of the target temperature (i.e., the temperature fluctuation of the temperature-sensitive element is controlled within a certain range), the control module controls the temperature driving module to perform high-sensitivity temperature adjustment according to the real-time high-sensitivity temperature information, so that the temperature of the temperature-sensitive element is controlled to a second accuracy of the target temperature (i.e., the temperature fluctuation of the temperature-sensitive element is controlled within a finer range);

[0007] The first precision is lower than the second precision; and the acquisition module includes an adjustable resistor.

[0008] Preferably, the acquisition module includes a temperature sensor, a high-sensitivity temperature acquisition module and a low-sensitivity temperature acquisition module;

[0009] The temperature sensor is used to collect the temperature of the temperature-sensitive element. The first end of the temperature sensor is grounded, and the second end of the temperature sensor is used as an input signal for the high-sensitivity temperature collection module and the low-sensitivity temperature collection module.

[0010] Preferably, the high-sensitivity temperature acquisition module is a differential amplifier circuit, in which the same-direction input terminal of the operational amplifier is connected to the second end of the temperature sensor, the reverse input terminal of the operational amplifier is connected to the first end of the third resistor, the second end of the third resistor is respectively connected to the first end of the first resistor and the first end of the fourth resistor, the second end of the fourth resistor is grounded, and the second end of the first resistor is connected to the positive electrode of the regulated power supply.

[0011] Preferably, the low-sensitivity temperature acquisition module is a voltage follower, the input end of the voltage follower is connected to the first end of the fifth resistor, the second end of the fifth resistor is connected to the second end of the temperature sensor and the first end of the second resistor, and the second end of the second resistor is connected to the positive electrode of the regulated power supply.

[0012] Preferably, the first resistor and the second resistor are adjustable resistors.

[0013] Preferably, the first resistor is a first load resistor of a first channel of the digital potentiometer, and the second resistor is a second load resistor of a second channel of the digital potentiometer.

[0014] Preferably, the resistance value and the second precision of the second resistor are determined according to the target temperature of the temperature-sensitive element.

[0015] Preferably, the resistance value of the first resistor is determined according to the resistance values ​​of the second resistor and the fourth resistor.

[0016] Preferably, the temperature sensor is a thermistor.

[0017] Preferably, the temperature driving module is a thermoelectric cooler.

[0018] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0020] Figure 1 A control schematic diagram of a dual-path temperature control system for a temperature-sensitive element provided in this application;

[0021] Figure 2 The circuit diagram of the acquisition module provided for this application;

[0022] Figure 3 The three-dimensional graph obtained according to formula (1) provided in this application;

[0023] Figure 4 A dual-path temperature control flow chart of the temperature-sensitive element provided in this application;

[0024] Figure 5 Temperature fluctuation and acquisition accuracy within the temperature acquisition range provided by this application;

[0025] Figure 6 The single-loop PID control effect diagram provided for this application;

[0026] Figure 7 This is the dual-loop PID control effect diagram provided for this application. DETAILED DESCRIPTION

[0027] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0028] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0029] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0030] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0031] The present application provides a dual-channel temperature control system for a temperature-sensitive element, which adjusts the temperature control range through adjustable resistors to achieve wide-range temperature control, and at the same time improves the control accuracy through dual-channel temperature acquisition and dual-precision temperature control. As a result, the working environment and performance of the temperature-sensitive element are significantly improved, ensuring that it can operate stably and reliably in high-precision application scenarios.

[0032] like Figure 1 As shown, the dual-path temperature control system of the temperature-sensitive element provided in the present application includes an acquisition module, a control module and a temperature driving module.

[0033] The acquisition module acquires the temperature of the temperature-sensitive element and outputs high-sensitivity temperature information and low-sensitivity temperature information. The acquisition module includes an adjustable resistor.

[0034] The temperature driving module is used to heat or cool the temperature-sensitive element to achieve dynamic adjustment of the real-time temperature of the temperature-sensitive element. The control module converts the low-sensitivity temperature information output by the acquisition module in real time into a digital signal (ADC analog-to-digital conversion), and performs low-sensitivity PID calculation based on the low-sensitivity temperature information, and uses the obtained low-sensitivity control information to control the temperature driving module to perform low-sensitivity temperature adjustment. When the temperature driving module controls the temperature of the temperature-sensitive element to the first accuracy of the target temperature (that is, the temperature fluctuation of the temperature-sensitive element is controlled within a certain range), the low-sensitivity temperature control is completed. After the low-sensitivity stable control is stable, the control module converts the high-sensitivity temperature information output by the acquisition module in real time into a digital signal, and performs high-sensitivity PID calculation based on the high-sensitivity temperature information, and uses the obtained high-sensitivity control information to control the temperature driving module to perform high-sensitivity temperature adjustment, so that the temperature of the temperature-sensitive element is controlled to the second accuracy of the target temperature (that is, the temperature fluctuation of the temperature-sensitive element is controlled within a finer range), and the high-sensitivity temperature control is completed at this time. Among them, the first accuracy is lower than the second accuracy.

[0035] The control module outputs a pulse width modulation (PWM) signal and a voltage signal with a suitable duty cycle to the temperature driving module to drive the temperature driving module.

[0036] As an embodiment, the temperature driving module is a thermoelectric cooler (TEC).

[0037] As an embodiment, the control module is a field programmable gate array (FPGA), and the FPGA includes a main program, a low-sensitivity PID control program, and a high-sensitivity PID control program.

[0038] As an example, Figure 2 As shown, the acquisition module includes a temperature sensor, a high-sensitivity temperature acquisition module and a low-sensitivity temperature acquisition module.

[0039] The temperature sensor is used to collect the temperature of the temperature-sensitive element. The first end of the temperature sensor is grounded, and the second end of the temperature sensor is used as an input signal for the high-sensitivity temperature collection module and the low-sensitivity temperature collection module.

[0040] As an example, Figure 2 As shown, the temperature sensor is a thermistor, such as a negative temperature coefficient thermistor (NTC). NTC has the characteristics of low cost, small size and wide measurement range, so the present application can perform temperature control on the temperature sensitive element in a wide temperature range.

[0041] As an example, Figure 2 As shown, the low-sensitivity temperature acquisition module is a voltage follower, the input end of the voltage follower (the same-direction input end of the operational amplifier 4) is connected to the first end of the fifth resistor R5, the second end of the fifth resistor R5 is connected to the second end of the temperature sensor NTC and the first end of the second resistor R2, and the second end of the second resistor R2 is connected to the positive electrode Vref of the regulated power supply.

[0042] like Figure 2 As shown, the second end of the temperature sensor NTC is also connected to the capacitor C2, and the other end of the capacitor C2 is grounded. The capacitor C2 plays a role of DC filtering for the low-sensitivity temperature acquisition module. The output end of the operational amplifier 4 is connected to the first end of the sixth resistor R6, and the second end of the sixth resistor R6 is grounded.

[0043] As an example, Figure 2 As shown, the high-sensitivity temperature acquisition module is a nonlinear amplifier circuit, specifically a differential amplifier circuit. In the differential amplifier circuit, the same-direction input terminal of the operational amplifier 3 is connected to the second terminal of the temperature sensor NTC, the reverse input terminal of the operational amplifier 3 is connected to the first terminal of the third resistor R3, the second terminal of the third resistor R3 is respectively connected to the first terminal of the first resistor R1 and the fourth resistor R4, the second terminal of the fourth resistor R4 is grounded, and the second terminal of the first resistor R1 is connected to the positive electrode Vref of the voltage-stabilized power supply. The differential amplifier circuit is used to improve the signal-to-noise ratio and sensitivity, and can detect wider voltage signal fluctuations when the temperature change is small, so as to more accurately capture the temperature change, thereby improving the temperature acquisition accuracy, so that higher-precision temperature control can be performed.

[0044] Preferably, the first resistor R1 and the second resistor R2 are both adjustable resistors.

[0045] On the basis of the above, preferably, Figure 2 As shown, the first resistor R1 is the first load resistor of the first channel 1 of the digital potentiometer (e.g., AD5143), and the second resistor R2 is the second load resistor of the second channel 2 of the digital potentiometer. The digital potentiometer is provided with a pin connected to the positive electrode Vref of the regulated power supply. The digital potentiometer can automatically adjust the resistance of the first load resistor and the second load resistor according to the target temperature range input by the user. Therefore, compared with the control circuit composed of resistors with fixed resistance values, the present application provides a wider temperature control range through the automatic adjustment function of the digital potentiometer.

[0046] based on Figure 2When the temperature of the thermistor changes, the resistance of the NTC will change nonlinearly, and its voltage division value is output through the output terminal OUT2 of the voltage follower. This port is for low-sensitivity temperature acquisition. The change value of the NTC voltage division value is also output through the output terminal OUT1 amplified by the differential amplifier circuit. This port is for high-sensitivity temperature acquisition, thereby outputting two temperature acquisition signals respectively.

[0047] Based on the digital potentiometer, the resistance value of the second resistor and the second precision are determined according to the target temperature of the temperature-sensitive element. The resistance value of the first resistor is determined according to the resistance value of the second resistor and the resistance value of the fourth resistor.

[0048] Specifically, based on Figure 2 For the circuit shown, the temperature change ΔT that can be detected when the ADC analog-to-digital conversion is at the minimum resolution (that is, the minimum temperature fluctuation that the control module can detect and process) is expressed as:

[0049]

[0050] Where, ΔV out1 It is the minimum resolution of ADC analog-to-digital conversion, indicating the smallest unit that can be collected during the acquisition process, and also the minimum temperature change value that can be distinguished, which is a fixed value. K is the amplification factor of the operational amplifier, T is the temperature of the temperature-sensitive element, R0 is the resistance of the thermistor at room temperature, B is the characteristic constant of the NTC (the characteristic constant of a 10K thermistor is 3455), and T0 is the reference normal temperature (usually 25°C).

[0051] In formula (1), the variables are ΔT, T and R2, and the others are constants. ΔT and T have a nonlinear relationship, and in order to obtain the best sensitivity at each temperature point, it can be adjusted by controlling the resistance value of the second resistor R2. According to formula (1), we can get Figure 3 The three-dimensional graph shown shows the relationship between the resistance of the second resistor R2, the temperature of the temperature-sensitive element and the accuracy of the high-sensitivity temperature acquisition module (shown as high-sensitivity accuracy, that is, the second accuracy).

[0052] As an example, for a specific temperature, the resistance values ​​of R1 and R2 are determined by the following method:

[0053] Figure 3 In the figure, a concave curve of the relationship between the R2 resistance and the high sensitivity accuracy is formed on the cross section perpendicular to the temperature coordinate value. For each temperature point, the curve has a minimum point (i.e., the point with the highest high sensitivity corresponding to the temperature). The R2 resistance corresponding to the minimum point is the R2 resistance matched with the temperature. At this time, the relationship between R2 and T is as follows:

[0054]

[0055] Therefore, after determining the target temperature of the temperature-sensitive element, the target temperature is input into the digital potentiometer through the PC end, and the digital potentiometer can automatically adjust the resistance value of the second load resistor to the corresponding R2 resistance value, and adjust the second accuracy to the accuracy corresponding to the lowest point. Thus, by changing the resistance value of the second load resistor to adjust the optimal sensitivity point of the target temperature, the accuracy of temperature control is improved.

[0056] Combination Figure 2 In the low-sensitivity temperature acquisition module, if the temperature of the temperature-sensitive element is certain, then when R2 is fixed, the partial pressure of the NTC is also certain. Therefore, for each temperature, R2 and the partial pressure of the NTC have a one-to-one correspondence.

[0057] On this basis, combined with Figure 2 , for the second channel 2 of the digital potentiometer, the second end of R2 is connected to the positive electrode Vref of the regulated power supply, and the first end of the temperature sensor NTC is grounded. Thus, Vref, R2 and NTC form a loop. For the first channel 1 of the digital potentiometer, the second end of R1 is connected to the positive electrode Vref of the regulated power supply, and the second end of the fourth resistor R4 is grounded. Thus, Vref, R1 and R4 form a loop. When the temperature of the temperature-sensitive element is determined, the resistance value of R2 and the voltage division of NTC are determined. When the voltage division of NTC is the same as the voltage division of the fourth resistor R4, the output value of the output terminal OUT1 of the differential amplifier circuit is 0, and high-sensitivity temperature control of the temperature is achieved at this time. Based on this, the resistance value of R1 that makes the voltage division of NTC and the voltage division of the fourth resistor R4 the same is used as the resistance value of the first load resistor corresponding to the temperature. T, R1, and R2 satisfy the following relationship:

[0058]

[0059] Therefore, after the target temperature of the temperature-sensitive element is determined and the target temperature is input into the digital potentiometer through the PC terminal, the digital potentiometer can automatically adjust the resistance value of the first load resistor to the corresponding resistance value of R1.

[0060] Therefore, by automatically adjusting the resistance value of R1, the resistance value of R2 and the second precision to match the target temperature through the digital potentiometer, high-precision temperature control can be ensured.

[0061] On the other hand, Figure 3In the figure, a curve of the relationship between temperature and high sensitivity precision is formed on the cross section perpendicular to the coordinate value of the R2 resistance value. It can be seen that different R2 resistance values ​​have different temperature control ranges and control precisions. By changing the R2 resistance value, the temperature control range and control precision can be changed. The user can select a suitable R2 resistance value according to the actual temperature control range and control precision. In addition, the first load resistor and the second load resistor of the digital potentiometer have a preset resistance range. According to formula (3), R1 or R2 is fixed, and different control temperatures can be determined by changing R2 or R1. Therefore, compared with the control circuit composed of resistors with fixed resistance values, the overall temperature control range of the present application is wider.

[0062] As an embodiment, the first accuracy is set to a constant value, that is, controlled within ±0.01°C.

[0063] Based on the above, in this application, Figure 4 As shown, the control flow of the control module is as follows:

[0064] S410: Receive low-sensitivity temperature information output in real time by the acquisition module.

[0065] S420: Calculate a first difference between the low-sensitivity temperature information and a preset low-sensitivity target temperature, and determine whether the first difference is greater than a first set value. If yes, execute S430; otherwise, execute S440.

[0066] The first setting value has a first accuracy, for example, controlled within ±0.01°C.

[0067] S430: Enter the low-sensitivity PID control program, and then execute S440.

[0068] Among them, in the low-sensitivity PID control process, in each PID cycle, the control module transmits the obtained low-sensitivity control information to the temperature driving module, and the temperature driving module drives the temperature-sensitive element to adjust the temperature and then feeds back the real-time temperature to the acquisition module, and then obtains new low-sensitivity temperature information and enters the next PID cycle. Until the first difference is less than or equal to the first set value, the low-sensitivity PID control program ends at this time.

[0069] S440: timing a preset time interval to allow the low-sensitivity temperature control to enter a stable state.

[0070] S450: Receive high-sensitivity temperature information output in real time by the acquisition module.

[0071] S460: Calculate the second difference between the high-sensitivity temperature information and the preset high-sensitivity target temperature, and determine whether the second difference is greater than the second set value. If yes, execute S470; otherwise, return to S410.

[0072] The second setting value has a second accuracy, for example, controlled within ±0.003°C.

[0073] S470: Enter the high-sensitivity PID control program, and then return to S410.

[0074] Among them, in the high-sensitivity PID control process, in each PID cycle, the control module transmits the obtained high-sensitivity control information to the temperature driving module, and the temperature driving module drives the temperature-sensitive element to adjust the temperature and then feeds back the real-time temperature to the acquisition module, and then obtains new high-sensitivity temperature information and enters the next PID cycle. Until the second difference is less than or equal to the second set value, the high-sensitivity PID control program ends at this time.

[0075] Among them, PID uses incremental PID, which reduces the computational complexity and has the characteristics of fast response in real-time systems. Dual-loop PID control can reduce overshoot and thus reduce control time.

[0076] Theoretically, according to the characteristics of the nonlinear amplifier circuit and equation (1), Figure 2 The circuit model shown has the highest sensitivity at 45°C.

[0077] Furthermore, in the experimental environment of about 27℃, R2 is 3000Ω, the temperature of the temperature-sensitive element is tested in the range of 15-75℃, the temperature is controlled by the dual-loop PID, and the 1200S data is measured after the system is stable, and the standard deviation of the corresponding temperature points in the range of 15-75℃ is calculated. The results are as follows: Figure 5 shown. Figure 5 The acquisition accuracy at 45°C is the highest, which is consistent with the theoretical calculation, proving that the control effect is best at 45°C. Figure 5 It can also be seen that the temperature fluctuation range is within 0.0062° C. In addition, the optimal temperature control point can be adjusted by adjusting the second load resistor R2.

[0078] When the dual-loop PID control is turned on and high sensitivity plus low sensitivity is used for control, the single-loop and dual-loop PID control diagrams are shown below: Figure 6 and 7 As shown. Figure 6It can be seen that when the single-loop PID channel is turned on, the low-sensitivity acquisition channel is entered for calculation. After the work tends to be stable, the temperature is basically stable at 34.987±0.01℃. It is found that the oscillation amplitude is too large during the control process. When the dual-loop PID channel is turned on, the work tends to be stable, and the data of 10000S is measured. The temperature is basically stable at 34.987±0.003℃, and its stability is significantly improved. The results show that after the nonlinear amplification circuit is used and controlled, the control accuracy is significantly improved, which also reflects the control advantages of the dual-loop PID, thereby ensuring that the temperature-sensitive element can work normally.

[0079] This application combines two-way temperature acquisition and a dual-loop incremental PID algorithm to achieve temperature control in the range of 15°C to 75°C. The accuracy of single-loop low-sensitivity PID control is ±0.01°C, while the accuracy of dual-loop PID control is increased to ±0.003°C.

[0080] In summary, this application can achieve a wide range of temperature adjustment and more precise temperature control within a specific frequency band through a dual-channel temperature acquisition circuit and dual-channel PID control, thereby significantly improving the working environment and performance of the temperature-sensitive element, ensuring that it can operate stably and reliably in high-precision application scenarios. In addition, the design has good portability and can be applied to other temperature control systems, and compared with the single-chip microcomputer system on the market, it provides better scalability, which makes this system have significant application value in the field of industrial intelligence.

[0081] Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are only for illustration, not for limiting the scope of the present application. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A dual-path temperature control system for a temperature-sensitive element, characterized in that: It includes an acquisition module, a control module and a temperature driving module; The acquisition module acquires the temperature of the temperature-sensitive element and outputs high-sensitivity temperature information and low-sensitivity temperature information; The control module controls the temperature driving module to perform low-sensitivity temperature adjustment according to the real-time low-sensitivity temperature information, and after the temperature of the temperature-sensitive element is controlled to a first accuracy of the target temperature, the control module controls the temperature driving module to perform high-sensitivity temperature adjustment according to the real-time high-sensitivity temperature information, so that the temperature of the temperature-sensitive element is controlled to a second accuracy of the target temperature; Among them, the first accuracy is lower than the second accuracy; and the acquisition module includes an adjustable resistor.

2. The dual-path temperature control system of the temperature-sensitive element according to claim 1, characterized in that: The acquisition module includes a temperature sensor, a high-sensitivity temperature acquisition module and a low-sensitivity temperature acquisition module; The temperature sensor is used to collect the temperature of the temperature-sensitive element. The first end of the temperature sensor is grounded, and the second end of the temperature sensor serves as an input signal for the high-sensitivity temperature collection module and the low-sensitivity temperature collection module.

3. The dual-path temperature control system of the temperature-sensitive element according to claim 2, characterized in that: The high-sensitivity temperature acquisition module is a differential amplifier circuit. In the differential amplifier circuit, the same-direction input terminal of the operational amplifier is connected to the second end of the temperature sensor, the reverse input terminal of the operational amplifier is connected to the first end of the third resistor, the second end of the third resistor is respectively connected to the first end of the first resistor and the first end of the fourth resistor, the second end of the fourth resistor is grounded, and the second end of the first resistor is connected to the positive electrode of the regulated power supply.

4. The dual-path temperature control system of the temperature-sensitive element according to claim 3, characterized in that: The low-sensitivity temperature acquisition module is a voltage follower, the input end of the voltage follower is connected to the first end of the fifth resistor, the second end of the fifth resistor is connected to the second end of the temperature sensor and the first end of the second resistor, and the second end of the second resistor is connected to the positive electrode of the regulated power supply.

5. The dual-path temperature control system of the temperature-sensitive element according to claim 4, characterized in that: The first resistor and the second resistor are the adjustable resistors.

6. The dual-path temperature control system of the temperature-sensitive element according to claim 5, characterized in that: The first resistor is a first load resistor of a first channel of the digital potentiometer, and the second resistor is a second load resistor of a second channel of the digital potentiometer.

7. The dual-path temperature control system of the temperature-sensitive element according to claim 4, characterized in that: The resistance value of the second resistor and the second accuracy are determined according to a target temperature of the temperature-sensitive element.

8. The dual-path temperature control system of the temperature-sensitive element according to claim 7, characterized in that: The resistance value of the first resistor is determined according to the resistance values ​​of the second resistor and the fourth resistor.

9. The dual-path temperature control system of the temperature-sensitive element according to claim 2, characterized in that: The temperature sensor is a thermal element.

10. The dual-path temperature control system of the temperature-sensitive element according to claim 1, characterized in that: The temperature driving module is a thermoelectric cooler.

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