Double-layer heating cooperative temperature control structure

Abstract

The invention discloses a double-layer heating cooperative temperature control structure, which adopts a double-layer structure comprising an outer-layer heating module, an inner-layer heating module and an isolating layer, wherein the outer-layer heating module is used for quickly heating and compensating heat loss through a spirally wound high-power density element; the inner layer heating module is embedded into an experimental object through a net-wound low thermal inertia heater to realize local fine temperature control, and thermal coupling interference between the inner layer heating module and the experimental object is reduced through an aerogel or ceramic fiber isolation layer with the thickness of 5-10 mm. The cooperative temperature control unit integrates fuzzy PID composite control, a self-adaptive robust control algorithm and multi-mode strategy dynamic adjustment, thermal coupling strength is fed back in real time through a heat flow sensor, an outer-layer high-power element and an inner-layer low-thermal-inertia element are controlled in a decoupling mode through a solid-state relay, and a double-ring framework is formed. The problems that a traditional single-layer heating system is large in temperature gradient, low in response speed, high in energy consumption and the like are solved, and the temperature control precision and the energy efficiency ratio are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature control, in particular to a double-layer heating cooperative temperature control structure applied to industrial equipment and experimental devices requiring high-precision temperature control. Background Art

[0002] In industrial production and scientific research, precise temperature control technology is crucial to product quality, experimental accuracy, and energy efficiency. Existing heating and temperature control technologies mainly rely on single-layer heating structures such as single heating wires and thin-film heaters combined with PID control algorithms to achieve temperature regulation. However, such solutions have the following problems:

[0003] (1) Poor temperature uniformity: The heat conduction direction of a single-layer heating structure is single, which easily leads to uneven temperature distribution in the heating area, especially in large or special-shaped equipment. For example, the radial temperature gradient of a large chemical reactor can reach ±5°C, and the local temperature difference of a special-shaped workpiece can even exceed ±10°C.

[0004] (2) Insufficient response speed and accuracy: The power adjustment range of single-layer heating is limited, making it difficult to achieve a dynamic balance between rapid heating and high-precision constant temperature. Traditional PID algorithms are prone to overshoot during rapid heating, and the adjustment time during the constant temperature stage is long.

[0005] (3) High energy consumption: To achieve the target temperature, single-layer heating needs to run at full power for a long time, resulting in large thermal inertia, low efficiency, and high energy consumption.

[0006] To address the above issues, existing technologies attempt to optimize through multi-zone independent temperature control devices, but they have defects such as complex systems, high costs, and insufficient coordination. Summary of the Invention

[0007] Aiming at the shortcomings of the existing technology, a double-layer heating and coordinated temperature control structure is proposed.

[0008] The present invention comprises:

[0009] The outer heating module is used to provide rapid temperature rise and compensate for ambient heat loss;

[0010] The inner heating module is used to perform local fine temperature adjustment on the object being measured;

[0011] An isolation layer is provided between the outer heating module and the inner heating module to reduce thermal coupling interference;

[0012] The collaborative temperature control unit is used to dynamically adjust the power distribution of the outer heating module and the inner heating module according to the temperature deviation and temperature change rate, so as to achieve rapid heating and high-precision constant temperature control.

[0013] Beneficial effects of the invention: The invention proposes a double-layer heating collaborative temperature control structure, which solves the problems of uneven temperature, delayed response and high energy consumption of traditional single-layer heating through the collaborative work of the inner and outer double-layer heating structures and dynamic control strategies such as fuzzy PID composite control and adaptive robust control, and realizes rapid heating and high-precision constant temperature control. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a double-layer heating and coordinated temperature control structure;

[0015] Figure 2 This is the logic block diagram of the temperature control method;

[0016] Figure 3 It is the collaborative temperature control curve;

[0017] Figure 4 Comparison of temperature fluctuations during the constant temperature stage. DETAILED DESCRIPTION

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0019] Figure 1 The figure shows a double-layer heating collaborative temperature control structure, which is particularly suitable for application scenarios such as chemical reactors, material heat treatment equipment, semiconductor manufacturing equipment, and biological culture equipment that have high requirements for temperature uniformity and response speed. The structure includes a carbonate solid 2 placed in the innermost cavity, an inner heating module 1, an outer heating module 3, an aerogel isolation layer 6, a thermocouple 4 (T1), and a thermocouple 5 (T2).

[0020] The outer heating module comprises a high power density heating element, which is installed on the outer frame of the equipment in a spiral winding manner, and is used for rapid temperature increase and compensation of environmental heat loss.

[0021] The inner heating module includes a low thermal inertia heater, which is installed on the outer side of the inner container wall in a mesh-like manner. The heating plates are distributed in a ring along the container wall, and heat is transferred to the object being measured (carbonate solid) in the container through the wall surface to achieve local fine temperature regulation.

[0022] The isolation layer is arranged between the outer and inner heating modules, is made of flexible insulation materials such as aerogel or ceramic fiber, has a thickness of 5-10 mm, and is used to reduce thermal coupling interference.

[0023] Collaborative temperature control unit: Integrating fuzzy PID composite control algorithm and adaptive robust control algorithm, the collaborative temperature control unit includes:

[0024] The temperature rise control module controls the outer module to perform full-power pulse heating (80% duty cycle) during the temperature rise phase (ΔT>20°C). The inner module dynamically adjusts the auxiliary power based on the real-time temperature difference (ΔT) and change rate (dT / dt) to shorten the overall temperature rise time.

[0025] The constant temperature control module controls the outer module to operate at low power to maintain the base temperature during the constant temperature stage (ΔT < 10°C). The inner module uses a fuzzy PID composite algorithm to correct local temperature fluctuations in real time, combined with robust compensation to suppress interference, and control temperature fluctuations within ±0.5°C.

[0026] The multi-modal switching module constitutes the execution core of the multi-modal control strategy, based on temperature deviation, rate of change and heat flux gradient , automatically switches between heating, transition, constant temperature and interference suppression modes. In the transition stage (10℃≤ΔT≤20℃), fuzzy PID compound control is started to achieve power coordinated regulation; dynamic weight distribution module, power distribution formula is:

[0027]

[0028]

[0029] in, It is the experimental calibration coefficient, which is defined as follows and dynamically adjusted according to the characteristics of the equipment:

[0030] k1 (external heating module deviation weight coefficient): The unit is W / °C. It controls the response intensity of the external heating power to the temperature deviation (ΔT) and determines the external basic power during the heating stage.

[0031] k2 (weight coefficient of change rate of outer heating module): unit is W s / ℃, controls the dynamic compensation sensitivity of the outer layer power to the temperature change rate (dT / dt);

[0032] k3 (inner layer heating module deviation weight coefficient): The unit is W / °C, which controls the fine adjustment benchmark of the inner layer heating power to the local temperature deviation;

[0033] k4 (weight coefficient of change rate of inner heating module): unit is W s / ℃, and suppress the overshoot of inner layer temperature fluctuation through negative feedback.

[0034] In some embodiments, the fuzzy PID composite control algorithm is implemented by a two-dimensional fuzzy controller, the input of which is the temperature deviation (ΔT) and the deviation change rate (dT / dt), which are normalized to the fuzzy domain by the quantization factor, and the output of the PID parameter correction value (ΔK p , ΔK i , ΔK d), the membership function adopts Gaussian curve, and the defuzzification strategy is the centroid method.

[0035] In some embodiments, the adaptive robust control algorithm introduces an extended state observer (ESO) to estimate the disturbance term in real time. ,The control law is the superposition of basic PID power and robust compensation power, and the robust gain γ is optimized through Lyapunov stability theory to ensure that the disturbance estimation error is small.

[0036] In some embodiments, the outer heating module uses high power density components such as silicon molybdenum rods, and the inner heating module uses nano-thin film heating sheets with low thermal inertia.

[0037] In some embodiments, high-precision heat flow sensors are added on both sides of the isolation layer to measure the heating heat flow in real time to dynamically adjust the fuzzy PID parameters; When the threshold is exceeded, a two-dimensional fuzzy PID controller is triggered to optimize power distribution:

[0038] Input heat flow deviation and temperature change rate , calculate the Δk1-Δk4 correction amount through the Gaussian membership function;

[0039] The power allocation formula is recalculated based on the revised k1-k4 to suppress thermal coupling interference and control temperature fluctuations within the threshold.

[0040] In some embodiments, the multimodal switching module includes:

[0041] Heating stage: The outer layer heats up rapidly, while the inner layer is preheated to prevent condensation;

[0042] Constant temperature stage: The inner layer is controlled by fine adjustment, combined with pulse PID control to achieve stable temperature control;

[0043] Interference suppression mode: When ΔT>5°C or a sudden load change is detected, the outer layer high-frequency modulation and the inner layer local compensation are activated synchronously.

[0044] Further, if Figure 2 As shown:

[0045] Heating stage: The outer heater operates in full power pulse mode to quickly increase the system temperature, and the inner heater ) and the rate of change ( ) Dynamically adjust power ( ) output auxiliary power, where k3 and k4 are calibrated through experiments and are used to compensate for local heat loss of the object being measured. Compared with the traditional single-layer heating system which takes 120s to heat up, the double-layer collaborative temperature control structure of this embodiment only takes 60s to complete the heating under the same conditions, which improves the efficiency by 50%. The curve of the heater power and the temperature change of the unit under test during the temperature control process is shown in the figure below. Figure 3 shown.

[0046] Constant temperature stage: the outer layer switches to low power mode, and the inner layer adopts fuzzy PID composite control combined with robust compensation. Figure 4 The temperature fluctuation in the constant temperature stage is controlled within ±0.3°C, while the fluctuation of the three traditional PID controls reaches ±1.2°C.

[0047] Interference suppression: When a sudden load change is detected When the outer layer starts high-frequency modulation, the inner layer performs local compensation. After the adaptive robust control is added, the system recovers stability within 10 seconds, and the overshoot is reduced by 80%.

[0048] Through the above-mentioned double-layer heating and coordinated temperature control, the heat generation of the sample can be accurately measured while meeting the requirements of temperature uniformity and response speed at different stages.

[0049] The above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, it may also include many other equivalent embodiments, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A double-layer heating coordinated temperature control structure, characterized in that: include: The outer heating module is used to provide rapid temperature rise and compensate for ambient heat loss; The inner heating module is used to perform local and fine temperature adjustment on the object being measured; An isolation layer is provided between the outer heating module and the inner heating module to reduce thermal coupling interference; The collaborative temperature control unit is used to dynamically adjust the power distribution of the outer heating module and the inner heating module according to the temperature deviation and temperature change rate, so as to achieve rapid heating and high-precision constant temperature control.

2. A double-layer heating cooperative temperature control structure according to claim 1, characterized in that: The outer heating module includes a high power density heating element and is installed on the outer frame of the device in a spiral winding manner.

3. The double-layer heating cooperative temperature control structure according to claim 1, characterized in that: The inner layer heating module includes a low thermal inertia heater, which is installed on the outer side of the inner layer container wall in a mesh-shaped attachment manner, and the heating plates are distributed in a ring along the container wall.

4. The double-layer heating coordinated temperature control structure according to claim 1, characterized in that: The isolation layer is made of flexible thermal insulation material and has a thickness of 5-10 mm.

5. A double-layer heating cooperative temperature control structure according to any one of claims 1 to 4, characterized in that: The collaborative temperature control unit includes: The temperature rise control module is used to control the full-power pulse heating of the outer heating module during the temperature rise stage, and the inner heating module dynamically adjusts the auxiliary power according to the real-time temperature difference and change rate; The constant temperature control module is used to control the outer layer acceleration module to operate at low power to maintain the basic temperature during the constant temperature stage, and the inner layer module uses the fuzzy PID composite algorithm to correct local temperature fluctuations in real time; The multi-mode switching module is used to automatically switch between heating, transition, constant temperature and interference suppression modes based on temperature deviation, rate of change and heat flux gradient.

6. The double-layer heating cooperative temperature control structure according to claim 5, characterized in that: The fuzzy PID composite control algorithm is implemented through a two-dimensional fuzzy controller. The input is the temperature deviation and the deviation change rate, which are normalized to the fuzzy domain through a quantization factor, and the PID parameter correction is output. The membership function adopts a Gaussian curve, and the defuzzification strategy is the center of gravity method.

7. The double-layer heating cooperative temperature control structure according to claim 5, characterized in that: The adaptive robust control algorithm introduces an extended state observer to estimate the disturbance term in real time. The control law is the superposition of basic PID power and robust compensation power. The robust gain is optimized through Lyapunov stability theory to ensure that the disturbance estimation error is small.

8. The double-layer heating coordinated temperature control structure according to claim 1, characterized in that: The outer heating module adopts silicon molybdenum rods, and the inner heating module adopts nano film heating sheets.

9. A double-layer heating cooperative temperature control structure according to claim 1 or 8, characterized in that: High-precision heat flow sensors are added on both sides of the isolation layer to measure the heating heat flow in real time to dynamically adjust the fuzzy PID parameters.

10. The double-layer heating coordinated temperature control structure according to claim 5, characterized in that: The multi-mode switching module includes: Heating stage: The outer layer heats up rapidly, while the inner layer is preheated to prevent condensation; Constant temperature stage: The inner layer is controlled by fine adjustment, combined with pulse PID control to achieve stable temperature control; Interference suppression mode: When a temperature deviation greater than a threshold or a sudden load change is detected, the outer layer high-frequency modulation and the inner layer local compensation are activated synchronously.

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