Heating frame temperature control method and system

Abstract

The invention discloses a heating frame temperature control method and system, and relates to the technical field of temperature control, and the method comprises the steps: carrying out the region division of a heating frame according to the heating task information, and obtaining a high-temperature region and a low-temperature region; calculating a parasitic alternating magnetic field generated on the low-temperature area according to a first alternating current parameter of a heating element in the high-temperature area; a preset number of heating elements are selected from all the heating elements of the heating frame to serve as magnetic field offset units; calculating a second alternating current parameter of the magnetic field offset unit according to the parasitic alternating magnetic field; the second alternating current parameter is applied to the magnetic field counteracting unit, so that the magnetic field counteracting unit generates a counteracting alternating magnetic field on the low-temperature area, and the counteracting alternating magnetic field and the parasitic alternating magnetic field are equal in size and opposite in direction. The temperature control of the heating frame is realized, and the accuracy and the reliability are improved.

Description

Technical Field

[0001] This invention relates to the field of temperature control technology, and in particular to a method and system for controlling the temperature of a heating rack. Background Technology

[0002] In the field of precision heat treatment, especially in the curing process of high-performance composite materials, it is often necessary to generate a non-uniform temperature field with fine and steep temperature gradients using a heating frame. These heating frames typically employ a high-density array of independent heating elements to precisely control local temperatures. However, when the heating elements in the heating zone operate at high power, the resulting alternating magnetic field may induce electromagnetic induction in inactive heating elements in adjacent areas, leading to parasitic eddy current heating and causing the actual temperature in the adjacent areas to be higher than expected. Traditional methods control temperature through power adjustment; however, the heat generated by electromagnetic induction is not actively supplied, making it impossible to regulate temperature by reducing the power in adjacent areas. Reducing the power of the heating zone itself to regulate temperature results in the heating zone failing to meet the required temperature, making it difficult to simultaneously meet the temperature requirements of different areas, leading to low temperature control accuracy and reliability.

[0003] In summary, the technical problems existing in the relevant technologies need to be improved. Summary of the Invention

[0004] The main objective of this invention is to propose a method and system for controlling the temperature of a heating frame, which can achieve temperature control of the heating frame by counteracting alternating magnetic fields, thereby improving accuracy and reliability.

[0005] On one hand, embodiments of the present invention provide a method for controlling the temperature of a heating frame, comprising the following steps: Based on the heating task information, the heating rack is divided into high-temperature and low-temperature zones; Based on the first alternating current parameters of the heating element in the high-temperature region, calculate the parasitic alternating magnetic field generated in the low-temperature region; A predetermined number of heating elements are selected from all the heating elements of the heating frame as magnetic field cancellation units; Calculate the second alternating current parameter of the magnetic field cancellation unit based on the parasitic alternating magnetic field; The second alternating current parameter is applied to the magnetic field cancellation unit so that the magnetic field cancellation unit generates a cancellation alternating magnetic field in the low temperature region. The cancellation alternating magnetic field is equal in magnitude and opposite in direction to the parasitic alternating magnetic field.

[0006] In some embodiments, when the magnetic field cancellation unit is used for magnetic field cancellation, calculating the second alternating current parameter of the magnetic field cancellation unit based on the parasitic alternating magnetic field includes: Based on the parasitic alternating magnetic field, a target linear equation system is constructed, wherein the number of solutions to the target linear equation system is the current amplitude and phase of the magnetic field cancellation unit; Based on the parasitic alternating magnetic field and the magnetic field contribution value of the magnetic field cancellation unit, the target linear equation system is solved using the least squares method to obtain the target current amplitude and target phase. The target current amplitude and the target phase are used as the second AC current parameters.

[0007] In some embodiments, when the magnetic field cancellation unit is used for both heating and magnetic field cancellation, calculating the second alternating current parameter of the magnetic field cancellation unit based on the parasitic alternating magnetic field includes: Calculate the heating current component of the magnetic field cancellation unit based on the heating task information; Based on the parasitic alternating magnetic field, calculate the magnetic field cancellation current component of the magnetic field cancellation unit; Calculate the composite alternating current parameters based on the heating current component and the magnetic field canceling current component; The composite AC current parameter is used as the second AC current parameter.

[0008] In some embodiments, calculating the composite alternating current parameters based on the heating current component and the magnetic field cancelling current component includes: Obtain the current temperature of the magnetic field cancellation unit; Based on the current temperature, calculate the component parameters of the magnetic field cancellation unit, including resistance parameters and inductance parameters; Update the heating current component and the magnetic field cancellation current component according to the component parameters; The updated heating current component and the magnetic field canceling current component are combined to obtain the composite alternating current parameters.

[0009] In some embodiments, calculating the magnetic field cancellation current component of the magnetic field cancellation unit based on the parasitic alternating magnetic field includes: Obtain the current temperature of the magnetic field cancellation unit; Calculate the geometric offset based on the current temperature and the thermal expansion characteristics of the material; Based on the geometric shape offset, calculate the geometric parameters and spatial coordinates of the magnetic field cancellation unit; The parasitic alternating magnetic field is updated based on the geometric parameters and the spatial coordinates; The magnetic field cancelling current component is calculated based on the updated parasitic alternating magnetic field.

[0010] In some embodiments, calculating the geometric offset based on the current temperature and the thermal expansion properties of the material includes: Obtain the current magnetic field strength and temperature change trend of the low-temperature region; The actual distribution and intensity of the parasitic alternating magnetic field are determined based on the current magnetic field strength, the temperature change trend, the current temperature, and the thermal expansion characteristics of the material. The geometric offset is calculated based on the actual distribution and intensity of the parasitic alternating magnetic field.

[0011] In some embodiments, determining the actual distribution and intensity of the parasitic alternating magnetic field based on the current magnetic field strength, the temperature change trend, the current temperature, and the thermal expansion characteristics of the material includes: Based on the current magnetic field strength, the temperature change trend, the current temperature, and the thermal expansion characteristics of the material, the low-temperature region is logically divided into sub-regions; In the sub-region, multiple target data are fused to obtain a fusion result, wherein the target data includes the current magnetic field strength or the temperature change trend; The fusion results are comprehensively analyzed to determine the actual distribution and intensity of the parasitic alternating magnetic field.

[0012] In some embodiments, fusing multiple target data to obtain a fusion result includes: Obtain data fluctuation information from the sensors in the sub-region; The interference status is determined based on the data fluctuation information; Based on the interference state, determine the data fusion weights; Based on the data fusion weights, multiple target data are fused to obtain the fusion result.

[0013] In some embodiments, the step of comprehensively analyzing the fusion results to determine the actual distribution and intensity of the parasitic alternating magnetic field includes: Obtain the frequency and phase of the alternating current of the heating element in the high-temperature region; Based on the frequency and phase, frequency and phase analysis is performed on the fusion result to obtain the magnetic field component consistent with the frequency and phase; The relationship between magnetic field strength and spatial position is determined based on the magnetic field components, the spatial position of the heating element in the high-temperature region, and the layout information of the sensor array in the low-temperature region. Based on the relationship between the magnetic field strength and spatial location, an intensity distribution map of the parasitic alternating magnetic field is generated; Based on the intensity distribution map, determine the actual distribution and intensity.

[0014] On the other hand, embodiments of the present invention provide a heating rack temperature control system, including: The region determination module is used to divide the heating rack into regions based on the heating task information, thus obtaining high-temperature regions and low-temperature regions; The parasitic magnetic field calculation module is used to calculate the parasitic alternating magnetic field generated in the low temperature region based on the first alternating current parameters of the heating element in the high temperature region. The magnetic field cancellation unit selection module is used to select a preset number of heating elements from all the heating elements of the heating frame as magnetic field cancellation units. The cancellation current parameter calculation module is used to calculate the second AC current parameter of the magnetic field cancellation unit based on the parasitic alternating magnetic field. A current application module is used to apply the second alternating current parameter to the magnetic field cancellation unit so that the magnetic field cancellation unit generates a cancellation alternating magnetic field in the low-temperature region, wherein the cancellation alternating magnetic field is equal in magnitude and opposite in direction to the parasitic alternating magnetic field.

[0015] The embodiments of this application include at least the following beneficial effects: First, the heating frame is divided into regions based on the heating task information to obtain a high-temperature region and a low-temperature region. Then, based on the first AC current parameter of the heating element in the high-temperature region, the parasitic alternating magnetic field generated in the low-temperature region is calculated. Next, a preset number of heating elements are selected from all the heating elements of the heating frame as magnetic field cancellation units. Based on the parasitic alternating magnetic field, the second AC current parameter of the magnetic field cancellation unit is calculated. Finally, the second AC current parameter is applied to the magnetic field cancellation unit so that the magnetic field cancellation unit generates a cancellation alternating magnetic field in the low-temperature region. Thus, the temperature control of the heating frame can be achieved by canceling the alternating magnetic field, thereby improving accuracy and reliability.

[0016] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description and the drawings. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a heating rack temperature control method according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a heating rack temperature control system according to an embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0020] In related technologies, traditional heating racks, when generating a non-uniform temperature field with a temperature gradient, produce an alternating magnetic field in the high-power heating area that induces electromagnetic induction in adjacent inactive low-temperature areas. This leads to parasitic eddy current heating, causing the actual temperature of the low-temperature areas to be higher than expected. Since this parasitic heat is not generated by active power supply, traditional power-adjustment-based temperature feedback control mechanisms are ineffective in addressing this issue, resulting in the control system's inability to simultaneously meet the temperature requirements of different areas.

[0021] For example, suppose a flat heating element is used to produce high-performance composite laminates, and it needs to perform a thermosetting task. Hundreds of individual sheet-like heating elements are arranged in a high-density array on the base of the heating element, each of which can be independently controlled by a central control unit to regulate its on / off state and power. The goal of this production task is to generate a specific temperature field on a piece of carbon fiber prepreg, requiring the central region A of the board to form a high-temperature curing zone of 185°C, while the surrounding annular region B, adjacent to region A, needs to be maintained at a low temperature below 60°C to prevent premature cross-linking of the resin in that region. To achieve this goal, the control system, according to preset logic, applies high-frequency alternating current to the cluster of heating elements corresponding to the central region A, causing it to operate at its rated power. Simultaneously, the system instructs all heating elements corresponding to the annular region B to be de-energized. However, after several minutes of operation, the sensor readings located within the low-temperature region B, adjacent to the boundary of the high-temperature region A, continue to rise, eventually stabilizing at around 85°C, far exceeding the process requirement of 60°C. After receiving the deviation signal, the control unit executes a feedback adjustment program. However, because the heating element corresponding to the abnormally high temperature point is in a shut-off state at the command level, its output power is zero, making it impossible to reduce power. The control system is in a control dilemma: it detects the need for cooling but cannot find an object to perform the cooling operation. This is because when the cluster of heating elements in the central region A operates at high power, the internal current generates an alternating magnetic field. This magnetic field passes through the heating elements, metal supports, and parallel power supply circuits in the adjacent, de-energized region B, inducing small but continuous eddy currents in the closed loop formed by these conductors according to the law of electromagnetic induction. These induced eddy currents continuously generate heat in the non-zero resistance components. This heat does not originate from the active output of the power supply system but is a parasitic electromagnetic byproduct of the main heating zone. Because the heat is continuously generated and cannot be cut off by conventional control methods, it accumulates continuously in the target low-temperature region B, eventually forming an unavoidable localized high-temperature zone.

[0022] If the aforementioned problems are not addressed, heating racks will be unable to control non-uniform temperature fields, especially in applications requiring temperature gradients, where the temperature in low-temperature regions will continuously deviate from the target value. This leads to uneven material curing, affecting the performance and quality of the final product. For example, composite materials may experience localized over-curing or under-curing, thus reducing their mechanical strength and dimensional stability. Furthermore, because traditional control systems cannot effectively intervene in this parasitic thermal effect, the system will fall into a control deadlock, unable to simultaneously meet the temperature requirements of different regions, thus limiting the application scope and efficiency of heating racks in the heat treatment field.

[0023] Faced with the aforementioned problems, this application initially considered reducing the heating power in the high-temperature region to weaken the magnetic field it generates, thereby reducing the parasitic heating effect in the low-temperature region. However, this method would cause the temperature in the high-temperature region to drop as well, failing to simultaneously meet the process requirements of the high-temperature region and disrupting the entire temperature field. This application recognizes that the root cause of the problem lies in the parasitic heat induced in the low-temperature region by the alternating magnetic field generated by the high-power heating element, and this heat cannot be eliminated by traditional power adjustment methods. Therefore, a method is needed to actively intervene and eliminate this parasitic magnetic field. This application further considers that if other heating elements on the heating element can be used to generate a counteracting magnetic field equal in magnitude and opposite in direction to the parasitic magnetic field, then the parasitic heating effect in the low-temperature region can be eliminated without affecting the normal operation of the high-temperature region, thereby achieving control of the non-uniform temperature field.

[0024] The embodiments of this application will be explained in detail below with reference to the accompanying drawings: Figure 1 This is an optional flowchart of a heating rack temperature control method provided in an embodiment of this application. Figure 1 The method may include, but is not limited to, steps S101 to S105.

[0025] Step S101: Based on the heating task information, divide the heating frame into regions to obtain high-temperature regions and low-temperature regions; Step S102: Calculate the parasitic alternating magnetic field generated in the low-temperature region based on the first alternating current parameters of the heating element in the high-temperature region; Step S103: Select a preset number of heating elements from all the heating elements of the heating frame as magnetic field cancellation units; Step S104: Calculate the second AC current parameters of the magnetic field cancellation unit based on the parasitic alternating magnetic field; Step S105: Apply the second alternating current parameter to the magnetic field cancellation unit so that the magnetic field cancellation unit generates a cancellation alternating magnetic field in the low temperature region. The cancellation alternating magnetic field and the parasitic alternating magnetic field are equal in magnitude and opposite in direction.

[0026] Steps S101 to S105 shown in the embodiments of this application can achieve temperature control of the heating frame by counteracting the alternating magnetic field, thereby improving accuracy and reliability.

[0027] In some embodiments, steps S101-S105 involve introducing a magnetic field cancellation unit and accurately calculating and applying a second alternating current parameter based on the calculated parasitic alternating magnetic field. This allows the magnetic field cancellation unit to generate a cancellation alternating magnetic field in the low-temperature region. The cancellation alternating magnetic field is equal in magnitude and opposite in direction to the parasitic alternating magnetic field, thereby effectively eliminating parasitic eddy current heat and achieving precise control of the non-uniform temperature field of the heating frame.

[0028] First, based on the heating task information, the heating frame can be divided into high-temperature and low-temperature zones. This defines the temperature targets and potential sources of electromagnetic interference and affected areas in different zones. To quantify the electromagnetic influence of the high-temperature zone on the low-temperature zone, the parasitic alternating magnetic field generated in the low-temperature zone can be calculated based on the first AC current parameters of the heating elements in the high-temperature zone. This is because the operating state of the heating elements in the high-temperature zone directly determines the characteristics of the magnetic field they generate. By obtaining the current parameters, the parasitic magnetic field induced in the low-temperature zone can be predicted and quantified. Then, a predetermined number of heating elements are selected from all the heating elements in the heating frame as magnetic field cancellation units. These selected elements will be responsible for generating the cancellation magnetic field. Next, based on the parasitic alternating magnetic field, the second AC current parameters of the magnetic field cancellation unit are calculated to ensure that the magnetic field cancellation unit can generate a cancellation magnetic field that matches the characteristics of the parasitic magnetic field. Through in-depth analysis of the parasitic magnetic field characteristics, parameters such as the current amplitude and phase required for cancellation can be obtained. Finally, the second AC current parameters are applied to the magnetic field cancellation unit to generate a cancellation alternating magnetic field in the low-temperature zone. The cancellation alternating magnetic field is equal in magnitude and opposite in direction to the parasitic alternating magnetic field. The offsetting effect reduces the total magnetic field strength in the low-temperature region, thereby suppressing the generation of parasitic eddy current heat.

[0029] It is understandable that the parasitic alternating magnetic field refers to the alternating magnetic field generated by the heating element in the high-temperature region, which is induced in the adjacent low-temperature region and may lead to undesirable eddy current thermal effects. It can be calculated using electromagnetic field simulation models, inversion algorithms based on measurement data, or a combination of both. Its main purpose is to identify and quantify the root cause of the abnormal temperature rise in the low-temperature region, providing a target for subsequent active cancellation. The magnetic field cancellation unit refers to the heating element selected from all the heating elements of the heating frame to generate the cancellation magnetic field. It can be an element originally used for heating in the heating frame, or a coil or element configured not for active heating but capable of generating a magnetic field. Its main purpose is to act as an actuator for active magnetic field cancellation, generating a magnetic field opposite to the parasitic magnetic field by applying a specific current. The cancellation alternating magnetic field refers to the alternating magnetic field generated by the magnetic field cancellation unit in the low-temperature region. It can be generated by applying an alternating current with specific parameters to the magnetic field cancellation unit. Its main purpose is to achieve magnetic field cancellation in the low-temperature region, eliminating or significantly reducing the parasitic eddy current thermal effect, so as to make it equal in magnitude and opposite in direction to the parasitic alternating magnetic field.

[0030] To illustrate this technical solution more clearly, a specific example is used below. When performing a heating task that requires generating a non-uniform temperature field, such as during the curing of composite materials, the control system first logically divides the overall plane of the heating frame into regions based on the set heating task configuration file. This can be done by dividing the heating frame into multiple high-temperature regions and multiple low-temperature regions based on the physical layout diagram and target temperature distribution diagram of the heating frame. For example, the central region is designated as the high-temperature region, while its outer ring-shaped region is designated as the low-temperature region. Next, to understand the electromagnetic influence of the high-temperature region on the low-temperature region, the system monitors the current and voltage of each heating element in the high-temperature region in real time, thereby obtaining its first AC current parameters, such as the instantaneous amplitude and phase of the current. Based on these parameters, combined with the geometric model of the heating frame and the electromagnetic properties of the material, the system can run an electromagnetic field simulation model, such as a finite element analysis-based software module, to calculate the spatial distribution and intensity of the parasitic alternating magnetic field generated by the high-temperature region in the low-temperature region. Subsequently, the system selects a preset number of heating elements from all available heating elements on the heating frame as magnetic field cancellation units. These magnetic field cancellation units are typically located at the boundary between high-temperature and low-temperature regions or within the low-temperature region, and their selection can be based on their location, electromagnetic coupling efficiency, or controllability. Based on this, the system uses optimization algorithms, such as least squares or gradient descent, to calculate the second AC current parameters applied to each magnetic field cancellation unit, according to the previously calculated distribution and intensity of the parasitic alternating magnetic field. These parameters include the current amplitude and phase, with the goal of ensuring that the magnetic field generated by the cancellation unit can cancel the parasitic magnetic field. Finally, a multi-channel programmable power management unit applies the calculated second AC current parameters to the selected magnetic field cancellation units. For example, if it is calculated that a certain cancellation unit requires a current with a predetermined amplitude and phase, the power management unit outputs the corresponding AC current. When these currents flow through the magnetic field cancellation units, they generate a canceling alternating magnetic field in the low-temperature region, which is controlled to be equal in magnitude and opposite in direction to the parasitic alternating magnetic field in the low-temperature region. In this way, the total magnetic field strength in the low-temperature region is reduced, thereby suppressing the generation of parasitic eddy current heat and ensuring that the temperature in the low-temperature region can be maintained within the target range, avoiding the temperature runaway problem caused by parasitic heat in traditional methods.

[0031] Through the above technical solution, this embodiment can solve the problem of inaccurate temperature control in the low-temperature region caused by the parasitic alternating magnetic field generated by the high-power heating area in the heating frame on the adjacent low-temperature region. By calculating and applying a counteracting alternating magnetic field, the heating frame can eliminate or weaken the parasitic eddy current thermal effect in the low-temperature region, thereby achieving control over the non-uniform temperature field of the heating frame. This allows the temperature targets of both the high-temperature and low-temperature regions to be met simultaneously in applications requiring steep temperature gradients, avoiding the control deadlock caused by parasitic heat in traditional control methods, and improving the accuracy and reliability of temperature control.

[0032] In some embodiments, in step S104, when the magnetic field cancellation unit is used for magnetic field cancellation, the second alternating current parameter of the magnetic field cancellation unit is calculated based on the parasitic alternating magnetic field, which may include, but is not limited to, the following steps: Based on the parasitic alternating magnetic field, a target linear equation system is constructed. The number of problems to be solved in the target linear equation system is the current amplitude and phase of the magnetic field cancellation unit. Based on the parasitic alternating magnetic field and the magnetic field contribution value of the magnetic field cancellation unit, the target linear equation system is solved using the least squares method to obtain the target current amplitude and target phase. The target current amplitude and target phase are used as the second AC current parameters.

[0033] In some embodiments, relying solely on preset models or static data makes it difficult to accurately calculate the second AC current parameter of the magnetic field cancellation unit. This is particularly problematic when the actual working environment is complex, the magnetic field distribution is uneven, or the heating element characteristics vary individually. This can lead to the cancellation alternating magnetic field failing to effectively cancel the parasitic alternating magnetic field, thus affecting the temperature control accuracy in low-temperature regions. To improve parameter calculation accuracy, a target linear equation system can be constructed based on the parasitic alternating magnetic field. The core of this equation system is to correlate the magnetic field contribution generated by each magnetic field cancellation unit with its respective current amplitude and phase, thereby abstracting the complex magnetic field cancellation task into a set of linear relationships. The solution variables for the target linear equation system are the current amplitude and phase of the magnetic field cancellation unit, meaning the equation system directly focuses on the key parameters controlling the magnetic field cancellation unit. Then, based on the parasitic alternating magnetic field and the magnetic field contribution values ​​of the magnetic field cancellation unit, the target linear equation system is solved using the least squares method to obtain the target current amplitude and target phase. During the solution process, not only is information about the parasitic alternating magnetic field considered, but the magnetic field contribution value of each magnetic field cancellation unit is also used as a known quantity for solving the target linear equation system. This is because different locations or types of magnetic field cancellation units produce different magnetic field effects in low-temperature regions, and introducing a magnetic field contribution value can improve the accuracy of the calculation. Furthermore, by using the target current amplitude and target phase as the second AC current parameters, the electromagnetic induction effect generated by the high-power heating region on the adjacent inactive region can be fundamentally resolved, effectively eliminating parasitic Joule heating.

[0034] Understandably, the target linear equations refer to a set of linear algebraic equations that mathematically transform the magnetic field cancellation problem. Specifically, this can be constructed by representing the superposition effect of the magnetic fields generated by each magnetic field cancellation unit in the low-temperature region as a linear combination of unknown current parameters. The aim is to transform a complex physical problem into a computable mathematical model. The number of unknown variables to be solved refers to the number of unknown variables that need to be determined in the target linear equations, specifically the current amplitude and phase of the magnetic field cancellation unit. The purpose is to directly solve for the key control parameters of the magnetic field cancellation unit. The magnetic field contribution value refers to the intensity and direction of the magnetic field generated by each magnetic field cancellation unit at a specific location in the low-temperature region. This can be determined through pre-simulation calculations, experimental measurements, or physical models based on the component geometry and material properties. The purpose is to quantify the influence of each cancellation unit on the total magnetic field, providing a basis for accurate cancellation.

[0035] To illustrate this technical solution more clearly, a specific example is used below. When a magnetic field cancellation unit is used for magnetic field cancellation, assume there are N monitoring points in the low-temperature region where the magnetic field needs to be cancelled, and M heating elements are selected as magnetic field cancellation units. First, the system constructs a target linear equation system based on the parasitic alternating magnetic field data measured or calculated at these N monitoring points. This equation system can be expressed in the form of where is an N-dimensional vector representing the complex amplitude of the parasitic alternating magnetic field at the N monitoring points; is an M-dimensional vector representing the complex amplitude of the current to be solved by the M magnetic field cancellation units; and A is an N×M matrix whose elements represent the magnetic field contribution value generated by the j-th magnetic field cancellation unit at the i-th monitoring point. These magnetic field contribution values ​​can be pre-calculated by modeling the geometry and material properties of the heating frame using electromagnetic simulation software, or measured through calibration experiments on the actual heating frame. Next, the least squares method is used to solve this target linear equation system to obtain the optimal solution. This solution process can be completed in an algorithm module running on a high-performance digital signal processor or embedded controller. The solution results will include the target current amplitude and target phase for each magnetic field cancellation unit. Finally, these calculated target current amplitudes and phases are used as second AC current parameters and applied to each magnetic field cancellation unit through the corresponding power supply drive circuit. For example, if the target current amplitude of a magnetic field cancellation unit is 0.5A and the target phase is 30 degrees, the control system will output a corresponding control signal to drive the power supply module to provide 0.5A of AC current with a phase of 30 degrees to that unit. In this way, each magnetic field cancellation unit can accurately generate its expected cancellation magnetic field, thereby forming a composite magnetic field in the low-temperature region that precisely matches and is opposite in direction to the parasitic magnetic field, achieving effective elimination of the parasitic magnetic field.

[0036] Through the above technical solution, this embodiment constructs a target linear equation system based on the parasitic alternating magnetic field and uses the current amplitude and phase of the magnetic field cancellation unit as the solution parameters, transforming the magnetic field cancellation problem into a quantifiable and computable mathematical model. By using the least squares method combined with the magnetic field contribution value of the magnetic field cancellation unit to solve this equation system, the optimal current amplitude and phase can be obtained from the complex magnetic field environment, thereby ensuring that the canceling alternating magnetic field generated by the magnetic field cancellation unit can achieve a high degree of matching with the parasitic alternating magnetic field. This effectively solves the problem of the difficulty in accurately calculating the cancellation current parameters using traditional methods, significantly improving the accuracy and efficiency of magnetic field cancellation. This, in turn, ensures that the temperature in the low-temperature region can be precisely controlled when the heating frame is working, avoiding interference from parasitic heat on the temperature field, and improving the performance and reliability of the overall temperature control system.

[0037] In some embodiments, in step S104, when the magnetic field cancellation unit is used for both heating and magnetic field cancellation, the second alternating current parameter of the magnetic field cancellation unit is calculated based on the parasitic alternating magnetic field, which may include, but is not limited to, the following steps: Step S201: Calculate the heating current component of the magnetic field cancellation unit based on the heating task information; Step S202: Calculate the magnetic field cancellation current component of the magnetic field cancellation unit based on the parasitic alternating magnetic field; Step S203: Calculate the composite AC current parameters based on the heating current component and the magnetic field canceling current component; Step S204: Use the composite AC current parameter as the second AC current parameter.

[0038] In some embodiments, when the magnetic field cancellation unit is used for both heating and magnetic field cancellation, a single control command can only control the magnetic field cancellation unit to perform either heating or magnetic field cancellation, making it difficult to achieve both simultaneously and increasing the complexity and control difficulty of the heating element. To enable the magnetic field cancellation unit to perform both heating and magnetic field cancellation functions simultaneously, the heating current component of the magnetic field cancellation unit can be calculated first based on the heating task information to ensure it can provide the heating power required for the low-temperature region. Then, based on the parasitic alternating magnetic field, the magnetic field cancellation current component of the magnetic field cancellation unit is calculated to generate an accurate cancellation alternating magnetic field. Next, based on the heating current component and the magnetic field cancellation current component, a composite alternating current parameter is calculated to ensure that the magnetic field cancellation unit can meet its heating requirements while performing the magnetic field cancellation task. Finally, the composite alternating current parameter is used as a second alternating current parameter, enabling the heating element, originally used only for magnetic field cancellation, to also undertake the heating task.

[0039] It is understandable that the heating current component refers to the current parameter calculated to enable the magnetic field cancellation unit to reach the preset temperature or provide the required heat, aiming to meet the basic functional requirements of the magnetic field cancellation unit as a heating element. Specifically, this can be determined by analyzing heating task information, such as target temperature, heating rate, and material thermal properties, combined with the resistance characteristics of the magnetic field cancellation unit itself, using power calculation formulas or proportional-integral-derivative (PID) control algorithms. The magnetic field cancellation current component refers to the current parameter calculated to effectively cancel the parasitic alternating magnetic field generated in the low-temperature region, aiming to ensure that the magnetic field cancellation unit can generate a canceling magnetic field that is equal in magnitude and opposite in direction to the parasitic magnetic field. Specifically, this can be determined by analyzing the intensity, frequency, and phase of the parasitic alternating magnetic field, combined with the geometry and electromagnetic characteristics of the magnetic field cancellation unit, using electromagnetic field theory or numerical simulation methods.

[0040] To illustrate this technical solution more clearly, a specific example is used below. Assume the heating point of the heating frame is continuously moving, and the magnetic field cancellation unit, used to generate the alternating magnetic field, also needs to perform its heating task. First, the control system receives heating task information regarding the transition from a low-temperature region to a high-temperature region, for example, a target temperature of 100°C. Based on this information, the system calculates the heating current component of the magnetic field cancellation unit. For example, if the resistance of the magnetic field cancellation unit is known, and a certain amount of power is required to maintain a temperature of 100°C, the system can calculate the required heating current amplitude. Simultaneously, through magnetic field sensors placed in the low-temperature region, the system can acquire the intensity, frequency, and phase information of the parasitic alternating magnetic field in real time. Based on this information, the system calculates the magnetic field cancellation current component of the magnetic field cancellation unit. For example, if the intensity of the parasitic magnetic field at a certain location is given, the system, using a pre-established magnetic field model or lookup table, determines that the magnetic field cancellation unit needs to generate a magnetic field of intensity and opposite phase, and then calculates the required current amplitude and phase to achieve this.

[0041] Next, the calculated heating current component and the magnetic field cancelling current component can be combined to obtain a composite AC current parameter. For example, if the heating current component is a purely resistive current (in phase with the voltage), while the magnetic field cancelling current component may contain inductive or capacitive components (with a phase difference from the voltage), these two AC current components can be combined into a single composite AC current parameter by vector superposition. This parameter contains a specific amplitude and phase. Finally, this composite AC current parameter is applied to the magnetic field cancelling unit. For example, a programmable AC power supply or drive circuit can precisely output a current with this composite AC current parameter. Thus, the magnetic field cancelling unit can provide the necessary heating for the low-temperature region while canceling parasitic alternating magnetic field interference, achieving a dual function.

[0042] Through the above technical solution, the magnetic field cancellation unit can simultaneously perform the dual tasks of heating and magnetic field cancellation, thus avoiding the need for separate heating elements for low-temperature regions. This significantly simplifies the overall structure of the heating element, reducing the number of components and wiring complexity. Furthermore, since a single unit can perform both functions, the control system does not need to manage independent heating and magnetic field cancellation loops, reducing the complexity and implementation difficulty of the control logic and improving the system's integration and reliability.

[0043] In some embodiments, step S203, calculating the composite alternating current parameters based on the heating current component and the magnetic field canceling current component, may include, but is not limited to, the following steps: Obtain the current temperature of the magnetic field cancellation unit; Based on the current temperature, calculate the component parameters of the magnetic field cancellation unit, including resistance and inductance parameters; Update the heating current component and the magnetic field cancellation current component based on the component parameters; The updated heating current component and the magnetic field cancellation current component are combined to obtain the composite alternating current parameters.

[0044] In some embodiments, the magnetic field cancellation unit experiences temperature changes during operation, affecting its component parameters. Ignoring these parameter changes can lead to inaccurate calculations of the composite AC current parameters, impacting the effectiveness of magnetic field cancellation and heating precision. To improve the accuracy of the composite AC current parameter calculation, the current temperature of the magnetic field cancellation unit can be obtained first. Since component parameters change with temperature, directly using preset current components or those without considering temperature effects can result in deviations. The component parameters of the magnetic field cancellation unit, including resistance and inductance parameters, can be calculated based on the current temperature, allowing for accurate understanding of the unit's electrical characteristics under actual operating conditions. Then, the heating current component and the magnetic field cancellation current component are updated based on these parameters, ensuring accurate prediction and control of the internal current distribution and magnetic field generation capability even when the unit's temperature changes. Finally, the updated heating current component and magnetic field cancellation current component are combined to obtain the composite AC current parameters. This allows the applied second AC current parameter to more accurately reflect actual requirements when the magnetic field cancellation unit is used for both heating and magnetic field cancellation.

[0045] To illustrate this technical solution more clearly, a specific example is provided below. First, to obtain the current temperature of the magnetic field cancellation unit, a high-precision thermocouple sensor can be installed on the surface of the unit or at a key location within it. This sensor collects temperature data in real time and converts the analog signal into a digital signal via an analog-to-digital converter (ADC), which is then transmitted to the control unit for processing. Next, based on the obtained current temperature, the component parameters of the magnetic field cancellation unit are calculated. For example, the temperature characteristics of the magnetic field cancellation unit can be pre-calibrated, establishing a lookup table or mathematical model between temperature and resistance and inductance values. Once the current temperature is obtained, the control unit can consult this lookup table or utilize the mathematical model to quickly calculate the resistance and inductance parameters of the magnetic field cancellation unit at the current temperature. For example, linear or nonlinear functions can be used to estimate the resistance parameter; a similar model can be used to calculate the inductance parameter.

[0046] Subsequently, the heating current component and the magnetic field cancellation current component are updated based on the calculated component parameters. For example, if the resistance of the magnetic field cancellation unit increases due to temperature rise, the heating current component may need to be adjusted accordingly to maintain the same heating power; simultaneously, to ensure that the strength and phase of the cancellation magnetic field remain unchanged, the magnetic field cancellation current component also needs to be corrected based on the new inductance parameters. This can be achieved by resolving the circuit equations containing the new component parameters or by using a preset compensation algorithm. For example, the impedance of the magnetic field cancellation unit can be recalculated based on the updated resistance and inductance parameters, and then the new heating current component and magnetic field cancellation current component can be derived from the target heating power and the target cancellation magnetic field strength. Finally, the updated heating current component and magnetic field cancellation current component are combined to obtain the composite AC current parameter. This typically involves vector superposition of the amplitude and phase of the two current components. For example, if the heating current component is and the magnetic field cancellation current component is , the composite AC current parameter can be obtained through complex number operations. The final composite AC current parameter, including its amplitude and phase, will be applied to the magnetic field cancellation unit to achieve precise heating and magnetic field cancellation functions.

[0047] Through the above technical solution, this embodiment effectively solves the problem that temperature changes during the operation of the magnetic field cancellation unit lead to changes in component parameters, resulting in inaccurate calculated composite AC current parameters. By acquiring the current temperature of the magnetic field cancellation unit in real time and accurately calculating its resistance and inductance parameters accordingly, the heating current component and the magnetic field cancellation current component are updated. The final synthesized composite AC current parameters can more accurately reflect the actual operating state of the magnetic field cancellation unit. This allows the current applied to the magnetic field cancellation unit to more precisely achieve the expected heating and magnetic field cancellation effects, thereby improving the accuracy of magnetic field cancellation and heating.

[0048] In some embodiments, in step S202, calculating the magnetic field cancellation current component of the magnetic field cancellation unit based on the parasitic alternating magnetic field may include, but is not limited to, the following steps: Step S301: Obtain the current temperature of the magnetic field cancellation unit; Step S302: Calculate the geometric offset based on the current temperature and the thermal expansion characteristics of the material; Step S303: Calculate the geometric parameters and spatial coordinates of the magnetic field cancellation unit based on the geometric shape offset. Step S304: Update the parasitic alternating magnetic field based on the geometric parameters and spatial coordinates; Step S305: Calculate the magnetic field canceling current component based on the updated parasitic alternating magnetic field.

[0049] In some embodiments, the temperature field of the heating element is not constant during operation, especially when the magnetic field cancellation unit itself is also used for heating, its temperature varies with operating time. This temperature change causes the geometry of the magnetic field cancellation unit to shift due to thermal expansion, thus affecting the magnetic field distribution it generates. This results in the previously calculated magnetic field cancellation current component becoming inaccurate and unable to effectively cancel the parasitic alternating magnetic field. To improve the accuracy of the magnetic field cancellation current component calculation, the current temperature of the magnetic field cancellation unit can be obtained first. Based on the current temperature and the thermal expansion characteristics of the material, the geometric shift of the magnetic field cancellation unit caused by temperature change can be calculated. Then, based on the geometric shift, the geometric parameters and spatial coordinates of the magnetic field cancellation unit can be calculated, reflecting its true state in physical space. Since the physical shape and position of the magnetic field cancellation unit change, the magnetic field distribution it generates in the surrounding space will also change accordingly. The parasitic alternating magnetic field can be updated based on the geometric parameters and spatial coordinates, ensuring an accurate characterization of the actual magnetic field environment. Finally, based on the updated parasitic alternating magnetic field, the magnetic field cancellation current component is calculated, so that the magnetic field cancellation unit can continuously generate a cancellation magnetic field that is equal in magnitude and opposite in direction to the parasitic magnetic field under the complex working condition of simultaneously heating and magnetic field cancellation, thereby effectively suppressing the generation of parasitic eddy current heat.

[0050] Understandably, geometric offset refers to the change in size and position of the magnetic field cancellation unit due to temperature variations. This can be calculated using the material's thermal expansion coefficient and the amount of temperature change, aiming to quantify the impact of temperature on the physical morphology of the magnetic field cancellation unit. Geometric parameters refer to the specific size, shape, and precise position of the magnetic field cancellation unit in three-dimensional space within the heating frame system. These parameters can include the unit's length, width, thickness, and bending radius, providing accurate physical model input for precise calculation of the magnetic field distribution. Spatial coordinates refer to the precise position of the magnetic field cancellation unit within the heating frame system, specifically including the three-dimensional coordinates of the unit's center point or key points. These coordinates also provide accurate physical model input for precise calculation of the magnetic field distribution.

[0051] To illustrate this technical solution more clearly, a specific example is used below. To obtain the current temperature of the magnetic field cancellation unit, a miniature thermocouple array can be integrated on the surface or inside each unit, or a non-contact temperature scan can be performed using an infrared thermal imager, and the acquired temperature data can be transmitted to the central control unit in real time. When calculating the geometric offset, the control unit can pre-store a database of thermal expansion coefficients for different materials (e.g., copper wire, ferrite core, support structure, etc.) and, combined with the current temperature provided by the temperature sensor, calculate the length, width, thickness, and minute changes in the overall position of each element using a linear or nonlinear thermal expansion model. For example, for an element of length *l*, the change in length after a temperature change can be expressed as where *l* is the linear expansion coefficient of the material. Then, based on the calculated geometric offset, the geometric parameters and spatial coordinates of the magnetic field cancellation unit can be updated. This may involve adjusting the vertex coordinates, center point coordinates, and geometric description of the conductor path of the magnetic field cancellation unit in the three-dimensional coordinate system. For example, if a coil's radius increases slightly due to thermal expansion, its radius parameter in the magnetic field model will be updated accordingly. Subsequently, to update the parasitic alternating magnetic field, a pre-established electromagnetic field simulation model, such as one based on the finite element method or boundary element method, can be used. The updated geometric parameters and spatial coordinates of the magnetic field cancellation element are used as input, and the simulation is rerun or interpolated using a pre-calculated lookup table to obtain the actual distribution and intensity of the parasitic alternating magnetic field generated in the high-temperature region under the current deformation state in the low-temperature region. For example, a three-dimensional mesh model can be constructed, mapping the geometry and position of each heating element and magnetic field cancellation element to the mesh, and then Maxwell's equations can be solved to obtain the magnetic field distribution. Finally, based on the updated parasitic alternating magnetic field, the magnetic field cancellation current component can be calculated. This can be done using the least squares method, gradient descent method, or other optimization algorithms. For example, an objective function representing the residual magnetic field intensity in the low-temperature region can be constructed, and then the accurate magnetic field cancellation current component can be obtained by minimizing this objective function by adjusting the current amplitude and phase of the magnetic field cancellation element. These calculations are typically performed by high-performance processors or dedicated digital signal processors to ensure real-time performance and accuracy.

[0052] Through the above technical solution, this embodiment can sense the temperature change of the magnetic field cancellation unit in real time and accurately calculate its geometric shape shift caused by thermal expansion. By incorporating this physical deformation information into the calculation process of the magnetic field cancellation current component, this embodiment can dynamically update the actual distribution of the parasitic alternating magnetic field, thereby ensuring that the calculated magnetic field cancellation current component always accurately matches the parasitic magnetic field under the current operating conditions. This allows the magnetic field cancellation unit to continuously and effectively cancel the parasitic alternating magnetic field even when its own temperature changes significantly, avoiding the decrease in cancellation accuracy caused by component deformation, thus maintaining the temperature stability in the low-temperature region. This effectively solves the problem of magnetic field cancellation failure caused by temperature changes in traditional solutions, ensuring the control accuracy and reliability of the heating frame in complex temperature field generation tasks.

[0053] In some embodiments, in step S302, calculating the geometric offset based on the current temperature and the thermal expansion characteristics of the material may include, but is not limited to, the following steps: Step S401: Obtain the current magnetic field strength and temperature change trend in the low-temperature region; Step S402: Determine the actual distribution and intensity of the parasitic alternating magnetic field based on the current magnetic field strength, temperature change trend, current temperature and material thermal expansion characteristics; Step S403: Calculate the geometric offset based on the actual distribution and intensity of the parasitic alternating magnetic field.

[0054] In some embodiments, considering only the current temperature and the thermal expansion characteristics of the material is insufficient, as changes in magnetic field strength and temperature trends in the low-temperature region also affect the thermal expansion of the material, thus impacting the accuracy of the geometric offset calculation and ultimately affecting the effectiveness of magnetic field cancellation. To improve the accuracy of the geometric offset calculation, the current magnetic field strength and temperature trend in the low-temperature region can be obtained first. This information represents dynamic factors affecting material deformation and magnetic field distribution. Changes in magnetic field strength may lead to magnetostriction in the material, while temperature trends reflect the rate of thermal expansion; both factors influence the geometry of the heating element. Then, based on the current magnetic field strength, temperature trend, current temperature, and the thermal expansion characteristics of the material, the actual distribution and intensity of the parasitic alternating magnetic field are determined. Through multi-dimensional data fusion and model correction, the modeling of the parasitic alternating magnetic field becomes closer to the actual physical situation. This embodiment considers the impact of dynamic changes in magnetic field and temperature on material deformation and its properties such as permeability and conductivity, thereby more accurately reflecting the true state of the parasitic alternating magnetic field in the low-temperature region. Finally, based on the actual distribution and intensity of the parasitic alternating magnetic field, the geometric offset is calculated, thereby improving the calculation accuracy.

[0055] Understandably, the current magnetic field strength refers to the magnitude of the magnetic field at a specific moment within a low-temperature region. This can be measured in real-time using a magnetic field sensor array, such as a Hall effect sensor or a magnetoresistive sensor for multi-point sampling. The temperature change trend refers to the rate and direction of temperature change over time within a low-temperature region. This can be calculated based on continuous temperature measurements using methods such as differential averaging, moving averages, or linear regression to reflect the rising or falling trend of temperature. The thermal expansion characteristics of a material refer to the inherent property of a material's volume or dimensions changing under temperature variations. This can be expressed as parameters such as the coefficient of thermal expansion and thermal expansion curves, which are typically obtained through experimental measurements or by consulting material handbooks. The actual distribution and intensity refer to the spatial distribution pattern and magnitude of the parasitic alternating magnetic field at various points within a low-temperature region, after comprehensively considering multiple influencing factors. This differs from theoretical calculations based solely on current parameters in high-temperature regions, reflecting the magnetic field conditions under actual physical environments.

[0056] To illustrate this technical solution more clearly, a specific example is used below. First, the current magnetic field strength and temperature change trend in the low-temperature region are acquired. This can be achieved by deploying a series of miniature Hall effect sensors and thermistor arrays at key locations in the low-temperature region. The Hall effect sensors can measure the magnetic field strength at each point in real time, while the thermistors provide accurate temperature readings. The control system can acquire this sensor data at a preset sampling frequency (e.g., 10 times per second). The temperature change trend can be obtained by performing first-order difference or moving average calculations on the continuously acquired temperature data; for example, calculating the average rate of temperature change over the past 5 seconds. Next, based on the acquired current magnetic field strength, temperature change trend, current temperature, and preset material thermal expansion characteristics, the actual distribution and intensity of the parasitic alternating magnetic field are determined. This can be achieved using a coupled finite element analysis (FEA) model. This FEA model pre-establishes the geometry and material properties of the heating element and uses the real-time acquired magnetic field strength, temperature, and calculated temperature change trend as boundary conditions or input parameters during operation. The model can incorporate magnetostriction and temperature-dependent thermal expansion models of the material to simulate the microscopic deformation of the material under dynamic changes in actual magnetic fields and temperatures. Through iterative calculations, the FEA model can output a precise three-dimensional distribution map of the parasitic alternating magnetic field in the low-temperature region under the current operating conditions, along with the magnetic field strength values ​​at each point. Finally, based on the actual distribution and strength of this determined parasitic alternating magnetic field, the geometric offset is calculated. This can be further accomplished using the aforementioned FEA model or an independent structural mechanics model. This model takes the actual magnetic field distribution and strength output by the FEA model as input, combines it with mechanical parameters such as the material's elastic modulus and Poisson's ratio, calculates the deformation of the heating frame structure caused by the magnetic field force, and superimposes it with the thermal expansion deformation caused by the current temperature and the material's thermal expansion characteristics. In this way, the overall geometric offset of the heating frame under the current complex operating conditions can be obtained; for example, the small displacement of the center position of a specific heating element relative to its initial design position, or the vertical deformation of a point on the surface of the heating frame.

[0057] Through the above technical solution, this embodiment can more comprehensively consider the factors affecting the geometric offset of the heating frame, including the changes in magnetic field strength and temperature trends in the low-temperature region. This makes the determination of the actual distribution and intensity of the parasitic alternating magnetic field more accurate, resulting in a more accurate calculated geometric offset. This helps to update the parasitic alternating magnetic field more precisely, thereby optimizing the current parameter calculation of the magnetic field cancellation unit, effectively suppressing parasitic eddy current heat in the low-temperature region, and ensuring that the heating frame can achieve precise temperature control of each region when generating a steep temperature gradient, avoiding temperature overshoot and control failure caused by parasitic heat.

[0058] In some embodiments, in step S402, determining the actual distribution and intensity of the parasitic alternating magnetic field based on the current magnetic field strength, temperature change trend, current temperature, and material thermal expansion characteristics may include, but is not limited to, the following steps: Step S501: Based on the current magnetic field strength, temperature change trend, current temperature and material thermal expansion characteristics, the low-temperature region is logically divided to obtain sub-regions; Step S502: In the sub-region, multiple target data are fused to obtain the fusion result. The target data includes the current magnetic field strength or temperature change trend. Step S503: Conduct a comprehensive analysis of the fusion results to determine the actual distribution and intensity of the parasitic alternating magnetic field.

[0059] In some embodiments, since calculations are performed directly based solely on overall data without regional optimization, the magnetic field strength and temperature change trend data may be affected by factors such as sensor noise, environmental electromagnetic interference, and uneven distribution. This can affect the accuracy of the actual distribution and strength of the parasitic alternating magnetic field, ultimately reducing the effectiveness of magnetic field cancellation. To improve calculation accuracy, the low-temperature region can be logically divided into several smaller sub-regions based on the current magnetic field strength, temperature change trend, current temperature, and material thermal expansion characteristics. These sub-regions can be analyzed independently. This division allows the analysis of complex low-temperature regions to be refined from the macroscopic to the microscopic level, enabling the capture of more subtle features of magnetic field and temperature changes within the region.

[0060] In each independent sub-region, multiple target data are fused to obtain a fusion result. By applying data fusion methods, such as weighted averaging or filtering algorithms, the inherent noise and environmental interference of single sensor data can be effectively reduced, improving the reliability and accuracy of the data, thus resulting in a more precise fusion result. The target data includes current magnetic field strength or temperature change trends from different sensors or at different time points. A comprehensive analysis of the fusion results determines the actual distribution and intensity of the parasitic alternating magnetic field. This comprehensive analysis may include correlation assessment, trend prediction, or pattern recognition of data from different sub-regions, thereby depicting the actual distribution and intensity of the parasitic alternating magnetic field throughout the entire cryogenic region. This depiction is comprehensive and accurate.

[0061] Understandably, logical partitioning refers to the process of logically dividing a large cryogenic region into several smaller sub-regions based on pre-defined rules or algorithms. These sub-regions can be independent or interconnected. This partitioning can be based on multiple dimensions such as spatial location, temperature gradient, magnetic field strength distribution, or sensor density. Its purpose is to refine and analyze the management of cryogenic regions, enabling differentiated processing based on the characteristics of different local areas.

[0062] To illustrate this technical solution more clearly, a specific example is provided below. First, in the low-temperature region of the heating frame, a sensor array consisting of multiple magnetic field sensors and temperature sensors can be deployed. These sensors are distributed at a certain density at different locations within the low-temperature region to collect magnetic field strength and temperature data at each point in real time. Based on the physical location information of these sensors, the system logically divides the entire low-temperature region into several grid-like sub-regions. For example, the low-temperature region can be divided into a 20x20 grid, with each grid corresponding to a sub-region. Each sub-region can contain one or more sensors. Within each sub-region, magnetic field strength data and temperature change trend data from all sensors within that sub-region can be collected over a period of time (e.g., 10 times per second). To improve data reliability, a Kalman filter can be used to fuse these target data. For example, for a certain sub-region, the data from multiple magnetic field sensors and temperature sensors within it are fused in real time using a Kalman filter to filter out random noise and measurement errors, resulting in a fused result of the magnetic field strength and temperature change trend for that sub-region. This fused result has higher smoothness and accuracy.

[0063] Then, a comprehensive analysis of the fusion results from all sub-regions is performed. This can include constructing a three-dimensional magnetic field distribution model, mapping the fusion result of each sub-region to its corresponding spatial location in the model. Using interpolation algorithms (e.g., bilinear interpolation or Kriging interpolation) and Fourier analysis, a parasitic alternating magnetic field intensity distribution map of the entire low-temperature region can be generated based on the fusion results. For example, the frequency and phase of the magnetic field components can be analyzed to identify the magnetic field components with the same frequency and phase as the alternating current of the heating element in the high-temperature region. Combined with the spatial location of the heating element and the layout information of the sensor array, the relationship between magnetic field intensity and spatial location can be determined. Finally, based on the generated intensity distribution map, the actual distribution and intensity of the parasitic alternating magnetic field can be determined, including its peak location, attenuation gradient, and overall spatial morphology, thus providing accurate input for subsequent magnetic field cancellation.

[0064] Through the above technical solution, this embodiment achieves refined perception and analysis of the magnetic field and temperature distribution within the low-temperature region by logically dividing the region. Within each sub-region, multiple target data are fused, significantly reducing errors and fluctuations from single data sources, improving data reliability and accuracy, and resulting in fusion results that more closely approximate reality. Furthermore, comprehensive analysis of the fusion results allows for a more comprehensive and accurate determination of the actual distribution and intensity of the parasitic alternating magnetic field, overcoming the bias in magnetic field assessment caused by inaccurate data in traditional methods. This embodiment provides a more accurate basis for subsequent magnetic field cancellation, significantly improving the accuracy and effectiveness of magnetic field cancellation, thereby ensuring the temperature control precision of the low-temperature region during the generation of complex temperature fields by the heating frame, and avoiding the negative impact of parasitic heat on process objectives.

[0065] In some embodiments, step S502 involves fusing multiple target data to obtain a fusion result, which may include, but is not limited to, the following steps: Acquire data fluctuation information from sensors in the sub-region; Determine the interference status based on data fluctuation information; Determine the data fusion weights based on the interference status; Based on the data fusion weights, multiple target data are fused to obtain the fusion result.

[0066] In some embodiments, sensors are susceptible to interference from various factors in practical applications, leading to data fluctuations that affect the accuracy of the fusion results. To improve fusion accuracy, data fluctuation information from sensors in sub-regions can be acquired first. Since sensors are easily affected by factors such as temperature, electromagnetic interference, or mechanical vibration in the actual environment, their output data may exhibit irregular fluctuations. By quantifying these fluctuations, it can be determined whether the sensor is in an interfered state. Then, based on the data fluctuation information, the interference state is determined, for example, by classifying it into different levels such as no interference, slight interference, or severe interference. This classification is the key basis for dynamically adjusting the data fusion weights. Next, based on the interference state, the data fusion weights are determined. Sensors with higher interference levels are assigned lower weights during the fusion process, and may even be completely excluded to reduce their negative impact on the final result; conversely, sensors with small data fluctuations and low interference levels are assigned higher weights. Finally, based on the data fusion weights, multiple target data are fused to obtain a fusion result, thus obtaining a more accurate and reliable fusion result.

[0067] Understandably, data fluctuation information refers to the degree to which the sensor's output data deviates from its average or expected value over a period of time. This can be obtained by calculating the standard deviation, variance, coefficient of variation, or rate of change over a continuous period, with the aim of quantifying the stability or reliability of the sensor data. Interference status refers to the degree or category of influence of external or internal factors on the sensor data. It can be classified into different levels based on a comparison of data fluctuation information with a preset threshold, such as no interference, slight interference, moderate interference, or severe interference. This aims to provide a basis for subsequent data fusion weight adjustments.

[0068] Through the above technical solution, this embodiment can accurately identify the interference state of sensors by acquiring and analyzing sensor data fluctuation information in real time, and dynamically adjust the weight of each sensor in the data fusion process accordingly. This enables the system to reduce or eliminate the negative impact of interfered sensor data on the final fusion result, thereby improving the accuracy and reliability of the fusion result. This improved data fusion result provides a more solid and reliable data foundation for subsequently determining the actual distribution and intensity of the parasitic alternating magnetic field, thus improving the accuracy and stability of the entire heating rack temperature control system.

[0069] In some embodiments, step S503 involves a comprehensive analysis of the fusion results to determine the actual distribution and intensity of the parasitic alternating magnetic field, which may include, but is not limited to, the following steps: Obtain the frequency and phase of the alternating current of the heating element in the high-temperature region; Based on the frequency and phase, frequency and phase analysis is performed on the fusion result to obtain the magnetic field components consistent with the frequency and phase. The relationship between magnetic field strength and spatial position is determined based on the magnetic field components, the spatial location of the heating element in the high-temperature region, and the layout information of the sensor array in the low-temperature region. Based on the relationship between magnetic field strength and spatial location, an intensity distribution map of the parasitic alternating magnetic field is generated; Based on the intensity distribution map, determine the actual distribution and intensity.

[0070] In some embodiments, the parasitic alternating magnetic field is affected by various factors, such as the current frequency and phase of the heating element in the high-temperature region, the spatial location of the heating element, and the layout of the sensor array in the low-temperature region. These factors may cause deviations between the actual distribution and intensity of the parasitic alternating magnetic field and the actual situation, thus affecting the effect of magnetic field cancellation. To accurately identify the actual distribution and intensity of the parasitic alternating magnetic field, the frequency and phase of the alternating current of the heating element in the high-temperature region can be obtained first. Based on the frequency and phase, frequency and phase analysis is performed on the fusion result to obtain the magnetic field component consistent with the frequency and phase. This allows for the accurate extraction of the magnetic field component consistent with the current frequency and phase of the heating element in the high-temperature region from the complex magnetic field data, effectively filtering out other interference signals and ensuring the purity of the analyzed magnetic field component. Then, considering the propagation characteristics of the magnetic field in space and the measurement limitations of the sensor array, the relationship between the magnetic field intensity and spatial location is determined based on the magnetic field component, the spatial location of the heating element in the high-temperature region, and the layout information of the sensor array in the low-temperature region. This allows for the construction of an accurate spatial distribution model of the magnetic field throughout the low-temperature region by combining the magnetic field measurement data with the spatial geometric information of the magnetic field source and measurement point. Then, based on the relationship between magnetic field strength and spatial location, an intensity distribution map of the parasitic alternating magnetic field is generated. This map visually displays the changes in magnetic field strength in space, providing a visual basis for ultimately determining the actual distribution and intensity. Finally, based on the intensity distribution map, the actual distribution and intensity are determined. Through in-depth analysis of the intensity distribution map, the actual distribution pattern and magnitude of the parasitic alternating magnetic field can be accurately identified.

[0071] Understandably, the magnetic field component refers to the magnetic field signal component extracted from the fusion results after frequency and phase analysis, which matches the frequency and phase of the alternating current of the heating element in the high-temperature region. It can be represented as the projection of magnetic field strength, magnetic flux density, or magnetic field vector at a specific frequency and phase. Its purpose is to accurately characterize the parasitic magnetic field directly caused by the heating element in the high-temperature region. The relationship between magnetic field strength and spatial location refers to the mathematical model or data structure describing the mapping relationship between the magnetic field strength value at each point in the low-temperature region and its corresponding spatial coordinates. This can be achieved using interpolation functions, finite element models, or pre-calibrated lookup tables. Its purpose is to establish the continuous or discrete distribution law of magnetic field strength in space. The intensity distribution map is an image that graphically displays the spatial distribution of the parasitic alternating magnetic field in the low-temperature region. It can be achieved using heat maps, contour maps, or three-dimensional maps. Its purpose is to provide a macroscopic and microscopic distribution view of the parasitic alternating magnetic field throughout the low-temperature region, facilitating intuitive understanding and subsequent analysis.

[0072] Through the aforementioned technical solution, based on the logical division of the low-temperature region and the fusion of target data, multiple key factors were further comprehensively considered, including the frequency and phase of the alternating current of the heating element in the high-temperature region, the spatial location of the heating element, and the layout of the sensor array in the low-temperature region. A detailed analysis and spatial relationship modeling of the fusion results were then performed. This enabled the accurate separation of the parasitic magnetic field component caused by the heating element in the high-temperature region from complex measurement data, and the accurate establishment of the mapping relationship between magnetic field strength and spatial location, thereby generating an intuitive intensity distribution map. Ultimately, the actual distribution and intensity of the parasitic alternating magnetic field could be accurately determined, significantly improving the accuracy and precision of the parasitic alternating magnetic field assessment. This provided a more accurate parameter basis for subsequent magnetic field cancellation, effectively enhancing the magnetic field cancellation effect and avoiding temperature control deviations caused by inaccurate magnetic field assessment.

[0073] The beneficial effects of implementing the embodiments of the present invention include: First, the heating frame is divided into regions according to the heating task information to obtain a high-temperature region and a low-temperature region. Then, based on the first AC current parameter of the heating element in the high-temperature region, the parasitic alternating magnetic field generated in the low-temperature region is calculated. Next, a preset number of heating elements are selected from all the heating elements of the heating frame as magnetic field cancellation units. Based on the parasitic alternating magnetic field, the second AC current parameter of the magnetic field cancellation unit is calculated. Finally, the second AC current parameter is applied to the magnetic field cancellation unit so that the magnetic field cancellation unit generates a cancellation alternating magnetic field in the low-temperature region. Thus, the temperature control of the heating frame can be achieved by canceling the alternating magnetic field, thereby improving accuracy and reliability.

[0074] like Figure 2 As shown, this embodiment of the invention also provides a heating rack temperature control system, including: The region determination module 601 is used to divide the heating frame into regions based on the heating task information, thereby obtaining high-temperature regions and low-temperature regions; The parasitic magnetic field calculation module 602 is used to calculate the parasitic alternating magnetic field generated in the low temperature region based on the first alternating current parameters of the heating element in the high temperature region. The magnetic field cancellation unit selection module 603 is used to select a preset number of heating elements from all the heating elements of the heating frame as magnetic field cancellation units. The cancellation current parameter calculation module 604 is used to calculate the second AC current parameter of the magnetic field cancellation unit based on the parasitic alternating magnetic field. The current application module 605 is used to apply the second alternating current parameter to the magnetic field cancellation unit so that the magnetic field cancellation unit generates a cancellation alternating magnetic field in the low temperature region. The cancellation alternating magnetic field is equal in magnitude and opposite in direction to the parasitic alternating magnetic field.

[0075] The content of the above method embodiments is applicable to this system embodiment. The specific functions implemented in this system embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0076] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

Claims

1. A method for controlling the temperature of a heating element, characterized in that, The following steps are involved: Based on the heating task information, the heating rack is divided into high-temperature and low-temperature zones; Based on the first alternating current parameters of the heating element in the high-temperature region, calculate the parasitic alternating magnetic field generated in the low-temperature region; A predetermined number of heating elements are selected from all the heating elements of the heating frame as magnetic field cancellation units; Calculate the second alternating current parameter of the magnetic field cancellation unit based on the parasitic alternating magnetic field; The second alternating current parameter is applied to the magnetic field cancellation unit so that the magnetic field cancellation unit generates a cancellation alternating magnetic field in the low temperature region. The cancellation alternating magnetic field is equal in magnitude and opposite in direction to the parasitic alternating magnetic field.

2. The method according to claim 1, characterized in that, When the magnetic field cancellation unit is used for magnetic field cancellation, the calculation of the second alternating current parameter of the magnetic field cancellation unit based on the parasitic alternating magnetic field includes: Based on the parasitic alternating magnetic field, a target linear equation system is constructed, wherein the number of solutions to the target linear equation system is the current amplitude and phase of the magnetic field cancellation unit; Based on the parasitic alternating magnetic field and the magnetic field contribution value of the magnetic field cancellation unit, the target linear equation system is solved using the least squares method to obtain the target current amplitude and target phase. The target current amplitude and the target phase are used as the second AC current parameters.

3. The method according to claim 1, characterized in that, When the magnetic field cancellation unit is used for both heating and magnetic field cancellation, the calculation of the second alternating current parameter of the magnetic field cancellation unit based on the parasitic alternating magnetic field includes: Calculate the heating current component of the magnetic field cancellation unit based on the heating task information; Based on the parasitic alternating magnetic field, calculate the magnetic field cancellation current component of the magnetic field cancellation unit; Calculate the composite alternating current parameters based on the heating current component and the magnetic field canceling current component; The composite AC current parameter is used as the second AC current parameter.

4. The method according to claim 3, characterized in that, The calculation of the composite alternating current parameters based on the heating current component and the magnetic field canceling current component includes: Obtain the current temperature of the magnetic field cancellation unit; Based on the current temperature, calculate the component parameters of the magnetic field cancellation unit, including resistance parameters and inductance parameters; Update the heating current component and the magnetic field cancellation current component according to the component parameters; The updated heating current component and the magnetic field canceling current component are combined to obtain the composite alternating current parameters.

5. The method according to claim 3, characterized in that, The step of calculating the magnetic field cancellation current component of the magnetic field cancellation unit based on the parasitic alternating magnetic field includes: Obtain the current temperature of the magnetic field cancellation unit; Calculate the geometric offset based on the current temperature and the thermal expansion characteristics of the material; Based on the geometric shape offset, calculate the geometric parameters and spatial coordinates of the magnetic field cancellation unit; The parasitic alternating magnetic field is updated based on the geometric parameters and the spatial coordinates; The magnetic field cancelling current component is calculated based on the updated parasitic alternating magnetic field.

6. The method according to claim 5, characterized in that, The step of calculating the geometric offset based on the current temperature and the thermal expansion characteristics of the material includes: Obtain the current magnetic field strength and temperature change trend of the low-temperature region; The actual distribution and intensity of the parasitic alternating magnetic field are determined based on the current magnetic field strength, the temperature change trend, the current temperature, and the thermal expansion characteristics of the material. The geometric offset is calculated based on the actual distribution and intensity of the parasitic alternating magnetic field.

7. The method according to claim 6, characterized in that, The step of determining the actual distribution and intensity of the parasitic alternating magnetic field based on the current magnetic field strength, the temperature change trend, the current temperature, and the thermal expansion characteristics of the material includes: Based on the current magnetic field strength, the temperature change trend, the current temperature, and the thermal expansion characteristics of the material, the low-temperature region is logically divided into sub-regions; In the sub-region, multiple target data are fused to obtain a fusion result, wherein the target data includes the current magnetic field strength or the temperature change trend; The fusion results are comprehensively analyzed to determine the actual distribution and intensity of the parasitic alternating magnetic field.

8. The method according to claim 7, characterized in that, The process of fusing multiple target data to obtain a fusion result includes: Obtain data fluctuation information from the sensors in the sub-region; The interference status is determined based on the data fluctuation information; Based on the interference state, determine the data fusion weights; Based on the data fusion weights, multiple target data are fused to obtain the fusion result.

9. The method according to claim 7, characterized in that, The comprehensive analysis of the fusion results to determine the actual distribution and intensity of the parasitic alternating magnetic field includes: Obtain the frequency and phase of the alternating current of the heating element in the high-temperature region; Based on the frequency and phase, frequency and phase analysis is performed on the fusion result to obtain the magnetic field component consistent with the frequency and phase; The relationship between magnetic field strength and spatial position is determined based on the magnetic field components, the spatial position of the heating element in the high-temperature region, and the layout information of the sensor array in the low-temperature region. Based on the relationship between the magnetic field strength and spatial location, an intensity distribution map of the parasitic alternating magnetic field is generated; Based on the intensity distribution map, determine the actual distribution and intensity.

10. A temperature control system for a heating rack, characterized in that, include: The region determination module is used to divide the heating rack into regions based on the heating task information, thus obtaining high-temperature regions and low-temperature regions; The parasitic magnetic field calculation module is used to calculate the parasitic alternating magnetic field generated in the low temperature region based on the first alternating current parameters of the heating element in the high temperature region. The magnetic field cancellation unit selection module is used to select a preset number of heating elements from all the heating elements of the heating frame as magnetic field cancellation units. The cancellation current parameter calculation module is used to calculate the second AC current parameter of the magnetic field cancellation unit based on the parasitic alternating magnetic field. A current application module is used to apply the second alternating current parameter to the magnetic field cancellation unit so that the magnetic field cancellation unit generates a cancellation alternating magnetic field in the low-temperature region, wherein the cancellation alternating magnetic field is equal in magnitude and opposite in direction to the parasitic alternating magnetic field.

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