Temperature generating device based on thermal differential double-loop control and temperature control method thereof

Abstract

The invention discloses a temperature generation device based on thermal differential double-loop control and a temperature control method thereof. The temperature generation device comprises a temperature generation unit, a double-channel sensor detection unit, a double-loop control conditioning unit, a thermal differential signal processing unit, a control instruction execution unit and a user interaction interface. The dual-channel sensor detection unit outputs temperature signals through two independent channels, so that the stability and reliability of the system are enhanced; due to the introduction of the double-loop control conditioning unit, precise processing and control of temperature signals are realized through differential amplification, gain control and cooperative work of an inner loop feedback assembly and an outer loop feedback assembly; the thermal differential signal processing unit can quickly process the temperature signal, execute a thermal differential algorithm, predict the temperature change trend, generate an accurate control instruction and adjust the working states of the heating element and the cooling element in a PWM control mode, and accurate control over the temperature is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature control, and in particular to a temperature generating device based on thermal differential double-loop control and a temperature control method thereof. Background Art

[0002] In the field of temperature control technology, accurate temperature regulation and fast response are key indicators for measuring the performance of temperature control devices. Most current temperature control devices use a single-loop control structure, that is, a temperature sensor monitors the temperature of the target area and feeds the temperature signal back to the controller. The controller adjusts the working state of the heating or cooling device according to the difference between the preset target temperature and the actual temperature to achieve temperature control.

[0003] However, the single-loop control structure has many shortcomings in practical applications. First, due to the response speed and accuracy limitations of the temperature sensor, the single-loop control system often cannot capture temperature changes in a timely and accurate manner, resulting in lag and error in temperature control. Second, when the ambient temperature changes greatly or there is external interference, the single-loop control system often finds it difficult to maintain a stable temperature output, resulting in large temperature fluctuations.

[0004] In order to overcome the shortcomings of the single-loop control structure, some advanced temperature control devices have begun to adopt a dual-loop control structure. The dual-loop control structure adds one or more auxiliary sensors or feedback links on the basis of the single-loop control to improve the accuracy and response speed of temperature control. However, most of these dual-loop control devices still rely on traditional control algorithms, such as PID (proportional-integral-differential) control algorithms, which often fail to achieve ideal control effects when dealing with rapid temperature changes or complex temperature control tasks.

[0005] In view of the above situation, the present invention aims to provide a new solution to solve this problem. Summary of the invention

[0006] In view of the above situation, in order to overcome the defects of the prior art, the purpose of the present invention is to provide a temperature generating device based on thermal differential double-loop control and a temperature control method thereof.

[0007] The technical solution is: a temperature generating device based on thermal differential double-loop control, the temperature generating device comprising:

[0008] A temperature generating unit, integrating heating elements and cooling elements, for generating and regulating temperature;

[0009] A dual-channel sensor detection unit, used to respectively collect temperature signals generated by the heating element and the cooling element during operation, and form two independent channels to output the collected temperature signals;

[0010] A dual-loop control conditioning unit, used for differential amplification and feedback regulation of the temperature signal;

[0011] A thermal differential signal processing unit, used to receive data from the dual-loop control signal processing circuit, calculate the temperature change trend using a thermal differential algorithm to extract temperature control information, and generate corresponding control instructions;

[0012] a control instruction execution unit, which performs temperature control on the temperature generating unit according to the control instruction provided by the thermal differential signal processing unit;

[0013] The user interface provides an intuitive operation interface that allows users to set target temperature, observe real-time temperature changes, and manually adjust control parameters.

[0014] Preferably, the dual-channel sensor detection unit includes a first temperature sensor for detecting the working temperature of the heating element, and a second temperature sensor for detecting the working temperature of the cooling element; one end of the first temperature sensor and the second temperature sensor are connected to a power supply VCC and grounded through a capacitor C1; the other end of the first temperature sensor is connected to resistor R1, resistor R3 and one end of capacitor C2, the other end of resistor R1 is connected to a first reference voltage source, the other end of capacitor C2 is grounded, and the other end of resistor R3 is connected to a first channel output end of the dual-channel sensor detection unit; the other end of the second temperature sensor is connected to resistor R2, resistor R4 and one end of capacitor C3, the other end of resistor R2 is connected to a second reference voltage source, the other end of capacitor C3 is grounded, and the other end of resistor R4 is connected to a second channel output end of the dual-channel sensor detection unit.

[0015] Preferably, the dual-loop control conditioning unit is configured as two independent and identical signal conditioning circuits, which correspond to two independent channels connected to the dual-channel sensor detection unit respectively; the signal conditioning circuit includes:

[0016] A differential amplifier component, used for differentially amplifying the temperature signal outputted from the first channel output terminal or the second channel output terminal of the dual-channel sensor detection unit to enhance the signal strength;

[0017] A gain control component for adjusting the signal gain during differential amplification;

[0018] The inner loop feedback component is used to respond to the change of the temperature signal immediately, and to achieve stable temperature control by integrating the differentially amplified signal;

[0019] The outer loop feedback component is used to perform closed-loop feedback regulation on the entire amplification process to suppress system errors.

[0020] Preferably, the differential amplifier component includes an op amp U1A and an op amp U1B, the inverting input terminal of the op amp U1A is connected to one end of a resistor R6 and the first channel output terminal of the dual-channel sensor detection unit through a resistor R5, the other end of the resistor R6 is connected to the inverting input terminal of the op amp U1B, the gain control component is arranged in the negative feedback network of the op amp U1A, the inner loop feedback component is arranged in the negative feedback network of the op amp U1B, and the outer loop feedback component is arranged between the output terminal of the op amp U1B and the non-inverting input terminal of the op amp U1A.

[0021] Preferably, a low-pass filter is also provided between the op amp U1A and the op amp U1B, and the low-pass filter includes a resistor R9 and a capacitor C11, one end of the resistor R9 is connected to the output end of the op amp U1A, and the other end of the resistor R9 is connected to the in-phase input end of the op amp U1B and is grounded through the capacitor C11.

[0022] Preferably, the gain control component includes a resistor R7, a resistor R8 and a field effect transistor Q1, one end of the resistor R7 and the resistor R8 are connected to the inverting input terminal of the operational amplifier U1A, the other end of the resistor R7 is connected to the drain of the field effect transistor Q1, the source of the field effect transistor Q1 and the other end of the resistor R8 are connected to the output terminal of the operational amplifier U1A, and the gate of the field effect transistor Q1 is connected to the thermal differential signal processing unit.

[0023] Preferably, the inner loop feedback component includes a resistor R10 and a capacitor C12, one end of the resistor R10 and the capacitor C12 are connected to the inverting input end of the operational amplifier U1B, and the other end of the resistor R10 and the capacitor C12 are connected to the output end of the operational amplifier U1B.

[0024] Preferably, the outer loop feedback component includes an op amp U1C, an inverting input terminal of the op amp U1C is connected to resistor R12 and one end of resistor R13, the other end of resistor R12 is connected to the adjustment end of an adjustable resistor RP1, one end of the adjustable resistor RP1 is connected to the output terminal of the op amp U1B, the other end of the adjustable resistor RP1 is connected to one end of capacitor C13 and the data receiving end of the thermal differential signal processing unit through resistor R11, the other end of capacitor C13 is grounded, the other end of resistor R13 is connected to the output terminal of the op amp U1C and one end of resistor R15 through capacitor C14, the other end of resistor R15 is connected to the non-inverting input terminal of the op amp U1A, and the non-inverting input terminal of the op amp U1C is grounded through resistor R14.

[0025] Preferably, the thermal differential signal processing unit is configured as an STM32F type single chip microcomputer.

[0026] A temperature control method for a temperature generating device based on thermal differential double-loop control, the method comprising:

[0027] The analog signal output from the dual-loop control signal processing circuit is sampled and converted into a digital signal through an analog-to-digital converter;

[0028] Convert the digital signal into a temperature value according to the digital signal and a calibration curve of the temperature sensor;

[0029] The temperature change rate is calculated using the thermal differential algorithm. The mathematical expression is:

[0030]

[0031] in, is the temperature change rate, T is the temperature value, and t is the time;

[0032] The thermal differential algorithm is used to predict the future temperature change trend. The mathematical expression is:

[0033]

[0034] Among them, T p (t+Δt) is the predicted future temperature value;

[0035] Calculate the error e(t) between the target temperature and the predicted temperature:

[0036] e(t)=T s -T p (t+Δt)

[0037] Among them, T s is the target temperature;

[0038] According to the error e(t), the control instruction is generated by the PID control algorithm. The mathematical expression of the PID control algorithm is:

[0039]

[0040] Among them, u(t) is the control instruction, K p , K i , K d They are proportional, integral, and differential control coefficients respectively;

[0041] The control instruction is sent to the control instruction execution unit to adjust the working state of the heating element and the cooling element.

[0042] Through the above technical solution, the beneficial effects of the present invention are:

[0043] 1. The setting of the dual-channel sensor detection unit in this application ensures the accurate acquisition of the working temperature of the heating and cooling elements, outputs the temperature signal through two independent channels, and enhances the stability and reliability of the system;

[0044] 2. The introduction of the dual-loop control conditioning unit realizes accurate processing and control of temperature signals through the coordinated work of differential amplification, gain control, inner loop and outer loop feedback components. The inner loop feedback component smoothes the temperature change trend through the integral regulator to reduce system fluctuations, while the outer loop feedback component effectively suppresses system errors through closed-loop negative feedback regulation, further improving the accuracy of temperature detection and the stability of the system;

[0045] 3. The thermal differential signal processing unit can quickly process temperature signals and execute thermal differential algorithms, predict temperature change trends, generate precise control instructions, and adjust the working states of heating and cooling elements through PWM control to achieve precise temperature control. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a module structure block diagram of the temperature generating device in the present invention.

[0047] Figure 2 The schematic diagram of the circuit for connecting the dual-channel sensor detection unit and the dual-loop control conditioning unit in the present invention.

[0048] Figure 3 It is a circuit function module diagram of the STM32F type single chip microcomputer in the present invention.

[0049] Figure 4 The figure is a flow chart of the temperature control method of the temperature generating device based on thermal differential double-loop control in the present invention. DETAILED DESCRIPTION

[0050] The above and other technical contents, features and effects of the present invention are described in detail below with reference to the attached Figure 1 To Attachment Figure 4 The detailed description of the embodiments will clearly show that the structural contents mentioned in the following embodiments are all based on the drawings in the specification.

[0051] Exemplary embodiments of the present invention will be described below with reference to the accompanying drawings.

[0052] like Figure 1 As shown, a temperature generating device based on thermal differential double-loop control comprises:

[0053] A temperature generating unit, integrating heating elements and cooling elements, for generating and regulating temperature;

[0054] A dual-channel sensor detection unit is used to respectively collect temperature signals generated by the heating element and the cooling element during operation, and form two independent channels to output the collected temperature signals;

[0055] Dual-loop control conditioning unit, used for differential amplification and feedback regulation of temperature signals;

[0056] A thermal differential signal processing unit, which is used to receive data from the dual-loop control signal processing circuit, calculate the temperature change trend by applying a thermal differential algorithm to extract temperature control information, and generate corresponding control instructions;

[0057] The control instruction execution unit controls the temperature of the temperature generating unit according to the control instruction provided by the thermal differential signal processing unit;

[0058] The user interface provides an intuitive operation interface that allows users to set target temperature, observe real-time temperature changes, and manually adjust control parameters.

[0059] In the above, the heating element in the temperature generating unit is used to increase the temperature, and the cooling element is used to reduce the temperature. The two elements work together to ensure that the temperature generating unit can quickly reach and maintain the target temperature set by the user.

[0060] In order to ensure the temperature control accuracy of the device on the temperature generating unit, a dual-channel sensor detection unit is set to collect the working temperature of the temperature generating unit. Figure 2 As shown, the dual-channel sensor detection unit includes a first temperature sensor RT1 for detecting the working temperature of the heating element, and a second temperature sensor RT2 for detecting the working temperature of the cooling element.

[0061] In a specific implementation, one end of the first temperature sensor RT1 and the second temperature sensor RT2 are connected to the power supply VCC and grounded through the capacitor C1; the other end of the first temperature sensor RT1 is connected to the resistor R1, the resistor R3 and one end of the capacitor C2, the other end of the resistor R1 is connected to the first reference voltage source VREF1, the other end of the capacitor C2 is grounded, and the other end of the resistor R3 is connected to the first channel output end OUT1 of the dual-channel sensor detection unit; the other end of the second temperature sensor RT2 is connected to the resistor R2, the resistor R4 and one end of the capacitor C3, the other end of the resistor R2 is connected to the second reference voltage source VREF2, the other end of the capacitor C3 is grounded, and the other end of the resistor R4 is connected to the second channel output end OUT2 of the dual-channel sensor detection unit.

[0062] When the heating element and the cooling element start working, the first temperature sensor RT1 and the second temperature sensor RT2 collect their working temperatures respectively and convert them into electrical signals for output. The two reference voltage sources are used to limit the output range of the electrical signal, which helps to standardize the output of the sensor so that the output signal can accurately reflect the actual change of the temperature and is not affected by the fluctuation of the power supply voltage. Capacitors C2 and C3 play a filtering role in the circuit, which helps to eliminate interference signals and improve the accuracy of the temperature signal. Finally, the processed temperature signals are output from the first channel output terminal OUT1 and the second channel output terminal OUT2 respectively.

[0063] In order to effectively process the temperature signals output by the two channels of the dual-channel sensor detection unit, the dual-loop control conditioning unit is configured as two independent and identical signal conditioning circuits in this embodiment, which are respectively connected to the two independent channels of the dual-channel sensor detection unit.

[0064] Specifically, the signal conditioning circuit includes:

[0065] A differential amplifier component, used for differentially amplifying the temperature signal outputted from the first channel output terminal or the second channel output terminal of the dual-channel sensor detection unit to enhance the signal strength;

[0066] A gain control component for adjusting the signal gain during differential amplification;

[0067] The inner loop feedback component is used to respond to the change of the temperature signal immediately, and to achieve stable temperature control by integrating the differentially amplified signal;

[0068] The outer loop feedback component is used to perform closed-loop feedback regulation on the entire amplification process to suppress system errors.

[0069] Taking the temperature signal processing of the first channel output in this application as an example, its workflow and function are described in detail. Figure 2 As shown, first, the differential amplifier component differentially amplifies the temperature signal of the first channel output terminal OUT1 to ensure that the signal maintains a high signal-to-noise ratio during transmission. In a specific embodiment, the differential amplifier component includes an op amp U1A and an op amp U1B, the inverting input terminal of the op amp U1A is connected to one end of the resistor R6 and the first channel output terminal of the dual-channel sensor detection unit through a resistor R5, the other end of the resistor R6 is connected to the inverting input terminal of the op amp U1B, the gain control component is arranged in the negative feedback network of the op amp U1A, the inner loop feedback component is arranged in the negative feedback network of the op amp U1B, and the outer loop feedback component is arranged between the output terminal of the op amp U1B and the non-inverting input terminal of the op amp U1A.

[0070] A low-pass filter is also provided between the op amp U1A and the op amp U1B, and the low-pass filter includes a resistor R9 and a capacitor C11, one end of the resistor R9 is connected to the output end of the op amp U1A, and the other end of the resistor R9 is connected to the in-phase input end of the op amp U1B, and is grounded through the capacitor C11. After the temperature signal output by the first channel is amplified by the differential amplifier component, the high-frequency noise is further filtered out by the low-pass filter, which helps to improve the signal-to-noise ratio of the signal and ensure that the signal received by the subsequent circuit is more stable and accurate.

[0071] In the above differential amplification process, the gain control component is set in the negative feedback network of the operational amplifier U1A to adjust the signal gain in the differential amplification process. Figure 2 As shown, the gain control component includes a resistor R7, a resistor R8 and a field effect transistor Q1, one end of the resistor R7 and the resistor R8 is connected to the inverting input terminal of the operational amplifier U1A, the other end of the resistor R7 is connected to the drain of the field effect transistor Q1, the source of the field effect transistor Q1 and the other end of the resistor R8 are connected to the output terminal of the operational amplifier U1A, and the gate of the field effect transistor Q1 is connected to the MCU analog voltage control (DAC1) terminal of the thermal differential signal processing unit.

[0072] In the gain control process, resistors R7 and R8 form a voltage divider resistor, and the field effect tube Q1 is used as a variable resistor. Its conduction degree is controlled by the analog voltage. By changing the conduction degree of the field effect tube Q1, the voltage divider ratio between resistors R7 and R8 can be adjusted, thereby changing the amplification gain of the op amp U1A. By adjusting the parameters of the gain control component as described above, the output signal gain can be accurately adjusted, and the performance and stability of the differential amplifier circuit can be improved. In practical applications, this gain control mechanism ensures that the circuit can dynamically adjust the amplification factor according to the intensity of the temperature signal and system requirements to adapt to various complex application scenarios.

[0073] In order to achieve accurate control of the temperature signal and effectively suppress system errors, the present application uses two feedback components, the inner loop and the outer loop, to work together to adjust the temperature signal. Specifically, Figure 2 As shown, the inner loop feedback component includes a resistor R10 and a capacitor C12, one end of the resistor R10 and the capacitor C12 are connected to the inverting input terminal of the operational amplifier U1B, and the other end of the resistor R10 and the capacitor C12 are connected to the output terminal of the operational amplifier U1B.

[0074] The outer loop feedback component includes an operational amplifier U1C, an inverting input terminal of the operational amplifier U1C is connected to resistor R12 and one end of resistor R13, the other end of resistor R12 is connected to the adjustment end of adjustable resistor RP1, one end of adjustable resistor RP1 is connected to the output terminal of the operational amplifier U1B, the other end of adjustable resistor RP1 is connected to one end of capacitor C13 and a data receiving end of a thermal differential signal processing unit through resistor R11, the other end of capacitor C13 is grounded, the other end of resistor R13 is connected to the output terminal of the operational amplifier U1C and one end of resistor R15 through capacitor C14, the other end of resistor R15 is connected to the non-inverting input terminal of the operational amplifier U1A, and the non-inverting input terminal of the operational amplifier U1C is grounded through resistor R14.

[0075] During the operation of the inner loop feedback component, resistor R10 and capacitor C12 form an integral regulator, which accumulates the change rate and time of the input signal of the operational amplifier U1B, thereby outputting a smooth signal that can reflect the temperature change trend and reduce system instability caused by temperature fluctuations.

[0076] During the operation of the outer loop feedback component, the output signal of the differential amplifier component is sampled through the adjustable resistor RP1 and sent to the operational amplifier U1C for enhanced processing. The resistor R13 and the capacitor C14 play a compensating role in the amplification of the sampled signal to maintain the stability of the feedback process. The output signal of the operational amplifier U1C is fed back to the in-phase input terminal of the operational amplifier U1A, thereby forming a closed-loop negative feedback regulation of the entire differential amplification process. When the system produces a fluctuation error due to external interference, the adjustment function of the outer loop feedback component can be used to quickly adjust the output signal to offset the error, effectively improving the accuracy of temperature detection and the stability of the system.

[0077] In a specific embodiment, the thermal differential signal processing unit is configured as a STM32F type single chip microcomputer. Figure 3 As shown in the figure, the microcontroller integrates high-speed processor core, rich peripheral interfaces and high-precision analog-to-digital converter (ADC) and other components. Among them, the built-in ADC of the STM32F microcontroller can quickly receive data from the dual-loop control signal processing circuit, and convert it from analog signal to digital signal, providing accurate input data for the thermal differential algorithm. In addition, the STM32F microcontroller also has a rich peripheral interface, which is convenient for data transmission and synchronous control with the user interface. The control instruction execution unit performs precise temperature control on the temperature generating unit through high-precision pulse width modulation (PWM) instructions according to the control instructions provided by the STM32F microcontroller.

[0078] Based on the same inventive concept, the embodiment of the present application also provides a temperature control method for a temperature generating device based on thermal differential double-loop control, such as Figure 4 As shown, the method includes:

[0079] The analog signal output from the dual-loop control signal processing circuit is sampled and converted into a digital signal through an analog-to-digital converter;

[0080] According to the digital signal and the calibration curve of the temperature sensor, the digital signal is converted into a temperature value; for example, the temperature sensor of the present application may adopt an NTC thermistor, and its calibration curve is a characteristic curve of the resistance value of the NTC thermistor changing with temperature. By inputting the characteristic curve model into the STM32F type microcontroller, the digital signal can be accurately converted into the corresponding temperature value;

[0081] The temperature change rate is calculated using the thermal differential algorithm. The mathematical expression is:

[0082]

[0083] in, is the temperature change rate, T is the temperature value, and t is the time;

[0084] The thermal differential algorithm is used to predict the future temperature change trend. The mathematical expression is:

[0085]

[0086] Among them, T p (t+Δt) is the predicted future temperature value;

[0087] Calculate the error e(t) between the target temperature and the predicted temperature:

[0088] e(t)=T s -T p (t+Δt)

[0089] Among them, T s is the target temperature;

[0090] According to the error e(t), the control instruction is generated by the PID control algorithm. The mathematical expression of the PID control algorithm is:

[0091]

[0092] Among them, u(t) is the control instruction, K p , K i , K d They are proportional, integral, and differential control coefficients respectively;

[0093] The control instruction is sent to the control instruction execution unit to adjust the working state of the heating element and the cooling element.

[0094] In the specific control process, the control instructions are passed to the control instruction execution unit in the form of PWM control. The control instruction execution unit integrates mature drive circuits. These circuits can respond to changes in PWM signals and quickly adjust the power of heating and cooling elements. After receiving the PWM signal, the heating element will control the on and off of the current according to the size of the duty cycle, thereby achieving precise control of the temperature. The cooling element is also controlled by the PWM signal, and the desired cooling effect is achieved by adjusting the flow of the cooling medium or the speed of the fan. The entire control process is dynamic. The system will monitor temperature changes in real time and adjust the PWM signal based on feedback to ensure that the temperature is maintained within the set target range. This control method not only improves the accuracy of temperature control, but also reduces energy consumption and extends the service life of the temperature generating unit.

[0095] The above is a further detailed description of the present invention in combination with a specific implementation method, and it cannot be determined that the specific implementation of the present invention is limited to this; for technical personnel in the technical field to which the present invention belongs and related technical fields, based on the technical solution of the present invention, the expansion and replacement of operating methods and data should all fall within the protection scope of the present invention.

Claims

1. A temperature generating device based on thermal differential double-loop control, characterized in that: The temperature generating device comprises: A temperature generating unit, integrating heating elements and cooling elements, for generating and regulating temperature; A dual-channel sensor detection unit, used to respectively collect temperature signals generated by the heating element and the cooling element during operation, and form two independent channels to output the collected temperature signals; A dual-loop control conditioning unit, used for differential amplification and feedback regulation of the temperature signal; A thermal differential signal processing unit, used to receive data from the dual-loop control signal processing circuit, calculate the temperature change trend using a thermal differential algorithm to extract temperature control information, and generate corresponding control instructions; a control instruction execution unit, which performs temperature control on the temperature generating unit according to the control instruction provided by the thermal differential signal processing unit; The user interface provides an intuitive operation interface that allows users to set target temperature, observe real-time temperature changes, and manually adjust control parameters.

2. The temperature generating device based on thermal differential double-loop control according to claim 1, characterized in that: The dual-channel sensor detection unit includes a first temperature sensor for detecting the working temperature of the heating element, and a second temperature sensor for detecting the working temperature of the cooling element; one end of the first temperature sensor and the second temperature sensor are connected to a power supply VCC and grounded through a capacitor C1; the other end of the first temperature sensor is connected to a resistor R1, a resistor R3 and one end of a capacitor C2, the other end of the resistor R1 is connected to a first reference voltage source, the other end of the capacitor C2 is grounded, and the other end of the resistor R3 is connected to a first channel output end of the dual-channel sensor detection unit; the other end of the second temperature sensor is connected to a resistor R2, a resistor R4 and one end of a capacitor C3, the other end of the resistor R2 is connected to a second reference voltage source, the other end of the capacitor C3 is grounded, and the other end of the resistor R4 is connected to a second channel output end of the dual-channel sensor detection unit.

3. The temperature generating device based on thermal differential double-loop control according to claim 2, characterized in that: The dual-loop control conditioning unit is configured as two independent and identical signal conditioning circuits, which are respectively connected to two independent channels of the dual-channel sensor detection unit; The signal conditioning circuit comprises: A differential amplifier component, used for differentially amplifying the temperature signal outputted from the first channel output terminal or the second channel output terminal of the dual-channel sensor detection unit to enhance the signal strength; A gain control component for adjusting the signal gain during differential amplification; The inner loop feedback component is used to respond to the change of the temperature signal immediately, and to achieve stable temperature control by integrating the differentially amplified signal; The outer loop feedback component is used to perform closed-loop feedback regulation on the entire amplification process to suppress system errors.

4. The temperature generating device based on thermal differential double-loop control according to claim 3 is characterized in that: The differential amplifier component includes an op amp U1A and an op amp U1B, the inverting input terminal of the op amp U1A is connected to one end of a resistor R6 and the first channel output terminal of the dual-channel sensor detection unit through a resistor R5, the other end of the resistor R6 is connected to the inverting input terminal of the op amp U1B, the gain control component is arranged in the negative feedback network of the op amp U1A, the inner loop feedback component is arranged in the negative feedback network of the op amp U1B, and the outer loop feedback component is arranged between the output terminal of the op amp U1B and the non-inverting input terminal of the op amp U1A.

5. The temperature generating device based on thermal differential double-loop control according to claim 4, characterized in that: A low-pass filter is also provided between the operational amplifier U1A and the operational amplifier U1B. The low-pass filter includes a resistor R9 and a capacitor C11. One end of the resistor R9 is connected to the output end of the operational amplifier U1A, and the other end of the resistor R9 is connected to the in-phase input end of the operational amplifier U1B and is grounded through the capacitor C11.

6. The temperature generating device based on thermal differential double-loop control according to claim 4, characterized in that: The gain control component includes a resistor R7, a resistor R8 and a field effect transistor Q1, one end of the resistor R7 and the resistor R8 is connected to the inverting input end of the operational amplifier U1A, the other end of the resistor R7 is connected to the drain of the field effect transistor Q1, the source of the field effect transistor Q1 and the other end of the resistor R8 are connected to the output end of the operational amplifier U1A, and the gate of the field effect transistor Q1 is connected to the thermal differential signal processing unit.

7. The temperature generating device based on thermal differential double-loop control according to claim 4, characterized in that: The inner loop feedback component includes a resistor R10 and a capacitor C12, one end of the resistor R10 and the capacitor C12 are connected to the inverting input end of the operational amplifier U1B, and the other end of the resistor R10 and the capacitor C12 are connected to the output end of the operational amplifier U1B.

8. The temperature generating device based on thermal differential double-loop control according to claim 4, characterized in that: The outer loop feedback component includes an operational amplifier U1C, an inverting input terminal of the operational amplifier U1C is connected to resistors R12 and one end of resistor R13, the other end of resistor R12 is connected to the adjustment end of an adjustable resistor RP1, one end of the adjustable resistor RP1 is connected to the output terminal of the operational amplifier U1B, the other end of the adjustable resistor RP1 is connected to one end of a capacitor C13 and a data receiving end of the thermal differential signal processing unit through a resistor R11, the other end of the capacitor C13 is grounded, the other end of the resistor R13 is connected to the output terminal of the operational amplifier U1C and one end of a resistor R15 through a capacitor C14, the other end of the resistor R15 is connected to the non-inverting input terminal of the operational amplifier U1A, and the non-inverting input terminal of the operational amplifier U1C is grounded through a resistor R14.

9. The temperature generating device based on thermal differential double-loop control according to claim 1, characterized in that: The thermal differential signal processing unit is configured as an STM32F type single chip microcomputer.

10. A temperature control method for a temperature generating device based on thermal differential double-loop control as claimed in any one of claims 1 to 9, characterized in that: The method comprises: The analog signal output from the dual-loop control signal processing circuit is sampled and converted into a digital signal through an analog-to-digital converter; Convert the digital signal into a temperature value according to the digital signal and a calibration curve of the temperature sensor; The temperature change rate is calculated using the thermal differential algorithm. The mathematical expression is: in, is the temperature change rate, T is the temperature value, and t is the time; The thermal differential algorithm is used to predict the future temperature change trend. The mathematical expression is: Among them, T p (t+Δt) is the predicted future temperature value; Calculate the error e(t) between the target temperature and the predicted temperature: e(t)=T s -T p (t+Δt) Among them, T s is the target temperature; According to the error e(t), the control instruction is generated by the PID control algorithm. The mathematical expression of the PID control algorithm is: Among them, u(t) is the control instruction, K p , K i , K d They are proportional, integral, and differential control coefficients respectively; The control instruction is sent to the control instruction execution unit to adjust the working state of the heating element and the cooling element.

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