An adaptive, scalable, modular induction heating system and its temperature control method

Abstract

This invention discloses an adaptive and scalable modular induction heating system and its temperature control method, belonging to the field of on-site remanufacturing and heat treatment technology for high-end equipment. The system includes multiple flexible induction heating modules, a distributed temperature sensing network, an intelligent controller, and a scalable power supply and communication bus system. Each flexible induction heating module consists of a multi-layered composite flexible substrate, induction coils arranged on a curved neutral surface, a split deformable magnetic core, and a strain sensor. The modules are spliced ​​together into a continuous curved surface heating array through a mechanical connection structure with integrated electrical interfaces. The intelligent controller generates a three-dimensional temperature field distribution in real time through a temperature field reconstruction unit and employs a dual closed-loop control algorithm including thermal inertia feedforward compensation and curvature compensation. This invention achieves on-site adaptive bonding and flexible expansion of the heating area for cold spraying repair of large and complex components, significantly improving heat treatment quality and on-site operation efficiency.

Description

Technical Field

[0001] This invention belongs to the field of high-end equipment on-site remanufacturing and heat treatment technology, specifically relating to an adaptive, scalable, modular induction heating system and its temperature control method for post-treatment of cold spray additive repair of large and complex components. Background Technology

[0002] In the fields of operation and maintenance and life extension of high-end equipment such as aerospace and marine equipment, core components such as aircraft skin, large structural parts, and marine crankshafts and propellers often suffer from wear, uniform corrosion, or localized damage due to long-term service. To ensure continuous equipment operation and reduce total life-cycle costs, on-site remanufacturing technology has emerged. Its typical process flow is: on-site surface cleaning → additive manufacturing technology repair such as cold spraying → post-heat treatment. Among them, post-heat treatment is the key link that determines the success or failure of the repair. Its core function is to eliminate the residual stress introduced by the cold spraying process in the repair area, promote the metallurgical bonding between the repair layer and the substrate, and homogenize the microstructure, thereby restoring or even improving the overall mechanical properties of the component.

[0003] However, the remanufacturing of large components intended for field service presents the following significant challenges in the subsequent heat treatment process: First, the geometry of large components to be repaired is usually extremely complex, often featuring curved surfaces, reinforcing ribs, irregular openings, and areas of varying thickness. Furthermore, the repair area often exhibits an irregular, asymmetrical local shape. Traditional methods such as fixed heating furnaces, heating blankets, or flame heating are insufficient to achieve dynamic contact with these complex curved surfaces, resulting in severely uneven temperature distribution in the repair area and heat-affected zone. This temperature unevenness not only fails to effectively eliminate residual stress but may also introduce new thermal stress, inducing secondary damage such as cracking of the repair layer and deformation of the substrate.

[0004] Secondly, the dimensions of components involved in on-site remanufacturing vary greatly, ranging from ship shafts a few meters long to wing panels tens of meters wide. Traditional heat treatment equipment is mostly of fixed size, and one set of equipment can only handle components of a certain specification range. If heating equipment is customized for each component of different sizes, not only will the manufacturing cycle be long and the equipment utilization rate low, but it will also bring unbearable equipment and logistics costs, which will seriously restrict the engineering promotion and economic viability of on-site remanufacturing technology.

[0005] Third, as a solid-state deposition process, cold spray additive repair technology involves the formation of the repair layer through high-speed particle impact and stacking during preparation. This typically results in high residual compressive stress within the layer, and the microstructure is in a metastable state. This places more stringent demands on the temperature control precision and uniformity of subsequent heat treatment. Any localized overheating or underheating can lead to insufficient bonding strength between the repair layer and the substrate, substandard microstructure uniformity, or even deterioration of the repair layer's performance.

[0006] Therefore, in the specific engineering scenario of on-site remanufacturing of large equipment, there is an urgent need for a post-heat treatment technology that can adaptively fit complex curved surfaces, flexibly expand the heating area according to the size of the components, and has high-precision closed-loop temperature control capabilities, so as to ensure the process quality and reliability of the cold spray repair layer and promote the on-site remanufacturing technology from the laboratory to the widespread engineering application.

[0007] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0008] The purpose of this invention is to provide a post-heat treatment technology solution that can adaptively fit complex curved surfaces, flexibly expand the heating area according to the size of the component, and has high-precision closed-loop temperature control capability.

[0009] To achieve the above objectives, the present invention provides the following solution: An adaptive, scalable, modular induction heating system, comprising: Multiple flexible induction heating modules, each of the flexible induction heating modules comprising: The flexible substrate is composed of a multi-layer composite structure including at least a working surface layer, an intermediate heat insulation layer and a backing layer. The working surface layer can generate elastic deformation when subjected to external pressure to conform to the complex curved surface of the component to be heated, and maintain the conformed curved surface shape after the pressure is removed. The induction coil is woven from multiple strands of Litz wire and is fixedly disposed between the intermediate heat insulation layer and the working surface layer. When the flexible substrate is in an unbent state, the induction coil is located on the bending neutral surface of the multilayer composite structure, so that when the flexible substrate bends, the inductance change rate of the coil remains within a preset threshold. The magnetic core is magnetically coupled to the induction coil and is composed of multiple separate magnetic chips connected to each other by flexible connectors, so that the magnetic core as a whole can change the shape of the magnetic circuit by following the bending of the flexible substrate. At least one strain sensor is used to detect the real-time bending curvature of the flexible induction heating module; Adjacent flexible induction heating modules are mechanically connected by at least one of flexible hinges, magnetic fasteners or elastic buckles set at the edge of the flexible substrate, and the electrical connection interfaces of power supply, communication and sensing signals integrated in the mechanical connection structure are connected simultaneously, thereby forming a continuous curved surface heating array that matches the shape and area of ​​the area to be heated. A distributed temperature sensing network, comprising multiple fiber optic temperature sensors or thin-film thermocouples, is arranged on the working surface of each flexible induction heating module and independently in the heat-affected zone, for real-time acquisition of temperature signals at each measurement point with a spatial resolution no less than a preset value. The intelligent controller is communicatively connected to the distributed temperature sensing network, the strain sensors of each flexible induction heating module, and their electrical interfaces; the intelligent controller includes: The temperature field reconstruction unit is used to receive the multi-point temperature signals, combine the spatial coordinates of each measurement point and execute a spatial interpolation algorithm to generate a three-dimensional temperature field distribution of the loading area in real time. The module location identification and mapping unit is used to automatically identify the address identifiers of each access module and their adjacent relationships through the communication handshake protocol, and to construct the topology diagram of the heating array. The power distribution calculation unit is used to compare the generated three-dimensional temperature field distribution with the target temperature process curve set by the user, obtain the temperature deviation and change trend of the corresponding local area of ​​each flexible induction heating module, and obtain the corresponding real-time curvature; based on the pre-calibrated and stored curvature-electromagnetic coupling efficiency mapping relationship, determine the induction heating efficiency correction factor of each module; adopt a dual closed-loop control algorithm including thermal inertia feedforward compensation and curvature compensation to generate an independent dynamic target power command for each flexible induction heating module to compensate for the difference in electromagnetic coupling efficiency and local heat capacity change caused by the change in the surface fitting state, and control the temperature field non-uniformity of the heating array within ±5℃; An scalable power supply and communication bus system includes a modular power supply unit and a communication bus; the modular power supply unit is configured to automatically allocate power according to the number of currently connected flexible induction heating modules; the communication bus supports hot-swapping and is used to transmit power commands and sensing data; when any flexible induction heating module is connected or removed, the intelligent controller completes module identification and power allocation recalculation through the communication bus in the first instance.

[0010] Optionally, the power distribution calculation unit of the intelligent controller uses a dual closed-loop control algorithm that includes thermal inertia feedforward compensation and curvature compensation to generate the target power command for the i-th flexible induction heating module in the following manner: Calculate temperature deviation (unit: °C) and the rate of change of deviation (Unit: ℃ / s), where Let T be the target temperature at the location of the i-th module at the current time t (in seconds). i (t) represents the measured temperature at that location; Call the preset equivalent heat capacity parameter C of the i-th module i(Unit: °C) and thermal inertia time constant (Unit: s), Calculate the thermal inertia feedforward power component. (Unit: W), where The rate of change of the target temperature over time; Based on the real-time bending curvature k obtained from the strain sensor of the i-th module i The induction heating efficiency correction factor corresponding to the current curvature is obtained by looking up a table from the curvature-electromagnetic coupling efficiency mapping relationship. The factor is defined as ,in For curvature k i The measured coupling efficiency value is as follows. Reference coupling efficiency when attaching a flat panel; Calculate the feedforward power component after curvature correction (Unit: W) The command power P is generated according to the following formula. cmd,i : Among them, K p (Unit: W / ℃), K i (Unit: W / (℃·s), K) d (Unit: W·s / ℃) represent the proportional, integral, and derivative control gains, respectively, and the intelligent controller adjusts at least the integral gain K based on the position of the i-th module in the heating array topology and its temperature coupling coefficient with adjacent modules. i Online adaptive adjustments are made to give modules located at the array edge or in areas with significant heat sink effects higher integral action strength.

[0011] Optionally, at least some of the fiber Bragg grating temperature sensors in the distributed temperature sensing network are embedded or attached to the surface of the working surface layer facing the component to be heated in an array with equal or non-equal spacing. The signal conditioning unit processes the original temperature signal through a weighted least squares filtering algorithm to suppress measurement noise and eliminate singular temperature values ​​caused by module splicing gaps.

[0012] Optionally, the flexible substrate has a plurality of airflow microchannels in the middle heat insulation layer. The airflow microchannels are connected to an external compressed air source and are used to introduce airflow during the heating or cooling stage to accelerate local temperature regulation or form a protective atmosphere.

[0013] Optionally, the curvature-electromagnetic coupling efficiency mapping relationship is pre-calibrated and stored in the intelligent controller in the following manner: In offline mode, a single flexible induction heating module is sequentially attached to test blocks with different standard radii of curvature, the same input power is applied, and the heat or heating rate reached on the surface of the test block is measured to establish a correspondence table between curvature and coupling efficiency correction factors; in the power distribution calculation unit, for the actual bending curvature between curvature data points in the correspondence table, linear interpolation or polynomial interpolation is used to obtain the corresponding correction factor.

[0014] Optionally, each flexible induction heating module also integrates a non-volatile memory, which stores the module's unique identification code, the factory-calibrated equivalent heat capacity Ci, the thermal inertia time constant, and the electromagnetic coupling characteristic curve under the reference plane. When the module is connected to the system through the electrical connection interface, the intelligent controller automatically reads these parameters to initialize the relevant control parameters in the power distribution calculation unit.

[0015] Optionally, the modular power unit in the scalable power and communication bus system includes a DC bus system and multiple DC / AC inverter modules. Each DC / AC inverter module provides high-frequency AC power to a group of flexible induction heating modules. The intelligent controller achieves independent power regulation of each flexible induction heating module by adjusting the DC bus voltage or the switching duty cycle of each inverter module.

[0016] Optionally, the intelligent controller also includes a process recording and traceability unit, which records the real-time power, measured temperature, bending curvature, and control parameters of each flexible induction heating module at a frequency of not less than 1Hz throughout the heat treatment process, and generates a searchable and replayable digital heat treatment report to support process optimization and quality traceability.

[0017] An adaptive, scalable, modular induction heating temperature control method based on the above system includes the following steps: Step S1: Based on the actual shape and size of the repair area of ​​the complex component to be heated, select the required number of flexible induction heating modules, and splice the modules into a continuous curved surface heating array covering the repair area and the heat-affected zone through the mechanical connection structure and integrated electrical interface, and arrange the sensors of the distributed temperature sensing network in place. Step S2: The system is powered on. The intelligent controller sends a query command through the communication bus to automatically identify the number of connected flexible induction heating modules, the address code of each module, the relative position, and the thermal parameters pre-stored in each module, and constructs the initial array topology and thermal model. Step S3: Input or call the target temperature process curve that matches the repair layer material and substrate into the intelligent controller through the human-machine interface. The curve at least defines the heating rate R. up Insulation temperature T hold Insulation time t hold and cooling rate R down ; Step S4: Start the heating process. The intelligent controller acquires the temperature data of the distributed temperature sensing network and the bending curvature data of the strain sensors of each module in real time, and continuously generates the three-dimensional temperature field of the heating area through the temperature field reconstruction unit. Step S5: The power distribution calculation unit, based on the deviation between the current three-dimensional temperature field and the target temperature process curve, and in conjunction with the equivalent heat capacity parameter C of each flexible induction heating module, i Thermal inertia time constant Induction heating efficiency correction factor corresponding to real-time curvature The target power command for each module is calculated periodically and sent. Step S6: During the heating phase, if the actual temperature change rate of a certain area is detected to be lower or higher than the preset rate, or if the local heat sink effect exceeds the preset range due to the structure on the back of the component, the intelligent controller actively adjusts the power command allocation of the affected module and its adjacent modules, and synchronously updates the correction factor. The computational basis is used to maintain the uniformity of the temperature field across the entire array; Step S7: When it is necessary to expand the coverage area during the heating process or when the heating area is insufficient, a new flexible induction heating module is connected to the edge of the heating array. The intelligent controller automatically identifies the new module, updates the array topology, incorporates the new module into the temperature field reconstruction and power distribution calculation, and completes the global power redistribution within one control cycle, so that the expanded heating array continues to meet the requirements of temperature non-uniformity. Step S8: After the heat preservation is completed, the intelligent controller controls the output power of each module according to the cooling rate of the target temperature process curve, and optionally introduces cooling airflow through the airflow microchannel to achieve controlled cooling.

[0018] Optionally, in step S5, the power allocation calculation unit calculates the target power command P of the i-th module. cmd,i The specific method is as follows: Among them, e i (t)=T target (t)-T i (t) represents the temperature deviation, T target (t) represents the target temperature at time t for the location corresponding to the i-th module. i(t) represents the measured temperature; C i and These are the equivalent heat capacity parameters and thermal inertia time constant obtained by the i-th module through self-identification, respectively; To determine the real-time bending curvature k of the i-th module i The induction heating efficiency correction factor is determined by looking up a table and interpolating. Furthermore, in step S6, when the intelligent controller determines that the temperature in a certain area deviates due to changes in local heat dissipation conditions, it also dynamically adjusts the integral gain K. i The adjustment amount is calculated based on the contribution of adjacent modules to the heat flow of this area.

[0019] Compared with the prior art, the present invention has the following beneficial effects: First, it has strong shape adaptability. Through the collaborative design of a multi-layered composite flexible substrate, an induction coil located on the bending neutral surface, a split deformable magnetic core, and an integrated strain sensor, each heating module can closely fit the complex curved surface component and maintain the stability of electromagnetic parameters in the bending state. This fundamentally solves the problem that traditional heating devices cannot adapt to complex geometric features such as curved surfaces and reinforcing ribs, which leads to severe uneven temperature fields.

[0020] Secondly, the heating area can be expanded indefinitely. The modules adopt a mechanical-electrical integrated quick-release connection structure, supporting hot-swapping and topology self-identification. Users can flexibly splice them on-site according to the size of the components, seamlessly covering the heating area from sub-square meters to hundreds of square meters. One system can handle various components with huge size differences, greatly reducing the cost of repeated equipment customization and logistics, resulting in significant economic benefits.

[0021] Third, it achieves high precision in temperature field control. It employs a dual closed-loop control algorithm that includes thermal inertia feedforward compensation and curvature compensation to reconstruct the three-dimensional temperature field in real time. The electromagnetic coupling efficiency factor is corrected based on the real-time bending curvature of each module. Combined with dynamically adaptively tuned PID parameters, it achieves precise temperature control under curved surfaces and irregular heat capacity distributions. The temperature field non-uniformity can be controlled within ±5℃.

[0022] Fourth, it exhibits strong process adaptability and reliability. The cold-sprayed repair layer is extremely sensitive to heat treatment temperature. This invention, through a distributed temperature sensing network and module-level independent power control, effectively avoids localized overheating or underheating, ensuring the effective elimination of residual stress in the repair layer, significantly improving metallurgical bonding strength, and resulting in a uniform and dense microstructure, meeting the stringent technical requirements of high-end equipment such as aerospace.

[0023] Fifth, efficient on-site deployment and convenient intelligent operation and maintenance. The modular quick-release structure allows installation and storage to be completed in minutes, supporting outdoor operations; the process recording and traceability unit records the operating data of each module throughout the process, generating searchable and replayable digital heat treatment reports, providing data support for process optimization and quality traceability. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the adaptive, scalable, modular induction heating temperature control method provided in an embodiment of the present invention. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The purpose of this invention is to provide a post-heat treatment technology solution that can adaptively fit complex curved surfaces, flexibly expand the heating area according to the size of the component, and has high-precision closed-loop temperature control capability.

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Example 1:

[0030] This embodiment provides an adaptive and scalable modular induction heating system that can be applied to on-site post-heat treatment processes following cold spraying repair of complex components such as aircraft air intakes and large structural parts. The system includes multiple flexible induction heating modules, a distributed temperature sensing network, an intelligent controller, and a scalable power supply and communication bus system.

[0031] The induction coil is braided from 100 strands of Litz wire, with each strand consisting of 0.1mm diameter enameled copper wire. This coil is fixedly positioned at the interface between the working surface layer and the intermediate heat insulation layer, precisely arranged on the curved neutral surface of the multi-layer composite structure. The position of the curved neutral surface was determined through finite element simulation and three-point bending experiments to ensure that when the flexible substrate undergoes bending deformation with a radius of curvature of not less than 150mm, the tensile or compressive strain amplitude in the coil region does not exceed 0.02%, and the resulting change in coil inductance does not exceed 0.5%. In its planar state, the induction coil has a square planar spiral pattern with 8 turns, the outermost layer measuring 180mm × 180mm, and a turn spacing of 5mm.

[0032] The magnetic core consists of 12 separate manganese-zinc ferrite magnetic chips, each with a cross-sectional dimension of 4mm × 8mm × 15mm. Adjacent magnetic chips are bonded together along the sides by flexible silicone rubber connecting sheets with a thickness of 0.3mm, forming a chain-like, flexible magnetic core array. When the flexible substrate bends, each separate magnetic chip can slip and rotate slightly relative to each other, allowing the magnetic core as a whole to bend with the substrate, maintaining effective magnetic coupling with the induction coil. Within a bending range where the radius of curvature varies from infinity (planar) to 150mm, the rate of change of the effective permeability of the magnetic core does not exceed 8%.

[0033] Each flexible induction heating module has a semiconductor strain gauge at each of its four corners, forming a full-bridge measurement circuit to detect the real-time bending curvature k of the module in two orthogonal directions. i The detection data is converted into digital signals by the conditioning circuit inside the module and then uploaded to the communication bus.

[0034] The distributed temperature sensing network includes an array of thin-film thermocouples integrated on the working surface of each module, as well as armored thermocouples that can be independently placed in the heat-affected zone. Each module surface has 25 thin-film thermocouple measurement points arranged in a 5×5 grid pattern (30mm×30mm), with a measurement point size of approximately 1mm×1mm, a response time of approximately 50ms, a temperature range of -50℃ to 400℃, and a resolution of 0.1℃. The temperature sensor signals from each module are processed by a signal conditioning unit, which uses a weighted least squares filtering algorithm to suppress measurement noise and eliminate outlier temperature values ​​that may be caused by gaps between modules.

[0035] Adjacent flexible induction heating modules are mechanically connected via flexible hinges and magnetic fasteners located at the module edges. Each module has three micro-engineering plastic flexible hinges spaced at intervals along its four edges, allowing relative rotation between adjacent modules within a range of -30° to +30° to accommodate changes in the curvature of the curved surface. Each of the four sides has a pair of neodymium iron boron permanent magnet fasteners at its center, providing an axial magnetic force of approximately 15N during engagement, ensuring a tight fit between the modules and the component surface and maintaining the connection. The electrical connection interface is integrated within the housing of the magnetic fasteners, with gold-plated elastic contacts and corresponding grooves on the mating surfaces. Simultaneously with mechanical engagement, this automatically connects the DC power supply line, the CAN communication bus differential signal line, and the temperature sensor signal shielding line. Thus, multiple modules can be integrated through mechanical and electrical connections to form a continuous curved surface heating array that matches the shape and area of ​​the region to be heated.

[0036] Each flexible induction heating module also integrates a non-volatile memory that stores the module's unique identification code and the factory-calibrated equivalent heat capacity parameter C. i and thermal inertia time constant The system also provides the electromagnetic coupling characteristic curves under the reference plane. When a module is connected to the system through the aforementioned electrical connection interface, the intelligent controller can automatically read these parameters to initialize the control model of each module.

[0037] The intelligent controller is implemented as an industrial embedded controller, equipped with an ARM Cortex-A72 quad-core processor and a real-time operating system. It communicates with all connected flexible induction heating modules via a CAN bus, with a data refresh cycle of 50ms. The intelligent controller includes a temperature field reconstruction unit, a module position identification and mapping unit, and a power distribution calculation unit.

[0038] The temperature field reconstruction unit receives multi-point temperature signals and spatial coordinates of each measurement point from a distributed temperature sensing network, and uses a three-dimensional spatial interpolation algorithm based on radial basis functions to generate the three-dimensional temperature field distribution of the heating area in real time. The module location identification and mapping unit broadcasts a topology query frame via the CAN bus. Each module returns its own unique identification code and mutual detection signals between adjacent modules. Based on this, the controller automatically constructs an undirected graph topology structure of the heating array to achieve self-identification and mapping between module addresses and physical locations.

[0039] The power distribution calculation unit is the core of the system. It compares the reconstructed three-dimensional temperature field with the user-preset target temperature process curve to obtain the temperature deviation and trend of the corresponding local area of ​​each module, and simultaneously acquires the real-time bending curvature k uploaded by the strain sensors of each module. i The power distribution calculation unit determines the induction heating efficiency correction factor for each module at the current curvature based on the pre-calibrated curvature-electromagnetic coupling efficiency mapping relationship stored in the controller. The calibration method for this mapping relationship is as follows: Under offline conditions, a single flexible induction heating module is attached to aluminum alloy test blocks with different standard radii of curvature (including convex and concave surfaces), and the same input power and frequency are applied. The surface temperature rise of the test blocks is measured within a specified time, with the temperature rise when the module is attached to a flat surface (curvature k=0) as the reference. For reference, a coupling efficiency correction factor is established for different curvatures k. The data table is used. For cases where the measured curvature falls between the data points in the table, linear interpolation is employed to obtain the corresponding values. .

[0040] The power distribution calculation unit employs a dual closed-loop control algorithm that includes thermal inertia feedforward compensation and curvature compensation to generate an independent dynamic target power command P for each flexible induction heating module. cmd,i This is to compensate for the differences in electromagnetic coupling efficiency and local heat capacity caused by changes in the curved surface bonding state, so that the temperature field non-uniformity of the entire heating array is controlled within ±5℃.

[0041] Specifically, the control algorithm for generating the power command of the i-th module is implemented as follows: Calculate temperature deviation (unit: °C), and the rate of change of deviation obtained based on sliding linear fitting. (Unit: ℃ / s), where T represents the target temperature (in °C) of the process curve at the current time t (in seconds). i (t) represents the measured temperature (in °C) of the region corresponding to this module. The equivalent heat capacity C, read from the module's memory, is then retrieved. i (Unit: J / ℃) and thermal inertia time constant (Unit: s), Calculate the thermal inertia feedforward power component. (Unit: W) Set the heating rate for the target temperature process curve. Then, find the correction factor from the mapping relationship based on the real-time bending curvature ki. Calculate the feedforward power components after curvature correction. (Unit: W). The final command power is generated according to the following formula: Among them, K p (Unit: W / ℃), K i (Unit: W / C·s), K d (Unit: W·s / ℃) represent the proportional, integral, and derivative control gains, respectively. The intelligent controller also adjusts the integral gain K based on the position of the i-th module in the heating array topology and the degree of temperature coupling influence of adjacent modules. iPerform online adaptive adjustment: For modules located at the array edge or in areas where the heat sink effect of the component structure is significant, appropriately increase K. i value, The scalable power and communication bus system includes modular power supply units and a CAN communication bus. The modular power supply units are supplied with DC bus voltage by AC / DC rectifiers and configured with multiple DC / AC high-frequency inverter modules, each driving a group of flexible induction heating modules. The intelligent controller independently adjusts the output power of each flexible induction heating module by controlling the DC bus voltage or switching duty cycle of each inverter module. The CAN bus communication rate is 1 Mbps, supporting hot-swapping of modules. When any flexible induction heating module is connected or removed, the intelligent controller can immediately identify and recalculate the power allocation for each module.

[0042] In addition, the intelligent controller is also equipped with a process recording and traceability unit, which records the real-time power, measured temperature, bending curvature and control parameters of each module at a frequency of not less than 1Hz throughout the entire heat treatment process, and generates a searchable and replayable digital heat treatment report to support process optimization and quality traceability.

[0043] Example 2:

[0044] This embodiment provides an adaptive, scalable, modular induction heating temperature control method based on the above system, the process of which is as follows: Figure 1 As shown. The method specifically includes the following steps: Step S1: Based on the actual shape and size of the complex component repair area to be heated, select the required number of flexible induction heating modules. Use flexible hinges and magnetic fasteners at the module edges to assemble the modules into a continuous curved heating array covering the repair area and surrounding heat-affected zone. Press each module to ensure its working surface is tightly fitted to the component surface. Simultaneously, complete the connection of the integrated electrical interface and place independent armored thermocouples at predetermined positions outside the array boundary.

[0045] Step S2: Upon system power-up, the intelligent controller sends a topology query command via the CAN communication bus to automatically identify the number of connected flexible induction heating modules, the address codes of each module, and their adjacency relationships. It also reads the equivalent heat capacity Ci and thermal inertia time constant pre-stored in the non-volatile memory of each module. Based on the reference electromagnetic coupling characteristic curve, the initial topology diagram and thermal model of the heating array are constructed.

[0046] Step S3: Input or call the target temperature process curve that matches the repair layer material and substrate in the intelligent controller through the human-machine interface. The curve parameters include at least the heating rate R. up Insulation temperature T hold and cooling rate R downFor example, for aluminum alloy cold spray repair layers, a typical process curve is: heating rate 5℃ / min, holding temperature 180℃, holding time 90min, and cooling rate 3℃ / min.

[0047] Step S4: Initiate the heating process. The intelligent controller collects temperature data from all thin-film thermocouples and boundary thermocouples in the distributed temperature sensing network in real time at a fixed control cycle (e.g., 50ms), and simultaneously collects the bending curvature signals output by the strain sensors of each module. Based on the collected discrete temperature values ​​and spatial coordinates, the temperature field reconstruction unit executes a spatial interpolation algorithm to continuously generate the three-dimensional temperature field distribution of the current heating area.

[0048] Step S5: In each control cycle, the power distribution calculation unit sequentially performs the following power command calculations for each flexible induction heating module: Calculate temperature deviation e i (t)=T target (t)-T i (t) (unit: °C) and its rate of change (unit: °C / s); obtain C from module parameters i (Unit: J / ℃) and (Unit: s); based on real-time bending curvature k i The induction heating efficiency correction factor was determined by referring to a table and interpolating. The target power command P for the i-th module is generated according to the following formula. cmd,i : Among them, e i (t)=T target (t)-T i (t) represents the temperature deviation (unit: °C), T target (t) represents the target temperature (in °C) at the location corresponding to the i-th module at time t (in seconds). i (t) represents the measured temperature (unit: °C); C i (Unit: J / ℃) and (Unit: s) represent the equivalent heat capacity parameter and thermal inertia time constant obtained by the i-th module through self-identification, respectively; To determine the real-time bending curvature k of the i-th module i The induction heating efficiency correction factor is determined by looking up a table and interpolating. The calculation results are sent to the power supply unit of the corresponding module via the CAN bus for execution.

[0049] Step S6: During the heating process, the intelligent controller continuously monitors the actual temperature change rate of each region. If it detects that a region's heating rate deviates from the preset rate or the temperature difference with adjacent regions exceeds a threshold due to local heat sink effect caused by the reinforcing ribs or variable thickness structure on the back of the component, it actively adjusts the power command allocation of the affected module and its adjacent modules, and adjusts the integral gain K. i Dynamic adjustments are made based on the heat flow contribution of adjacent modules to the region, in order to maintain the uniformity of the temperature field across the entire array.

[0050] Step S7: If it is found during the heating process that the existing heating area is insufficient to fully cover the area required by the process, a new flexible induction heating module can be added to the edge of the heating array without shutting down the system. The intelligent controller automatically identifies the access of the new module through hot-plug detection, updates the array topology, incorporates the new module into the temperature field reconstruction and power distribution calculation, and completes the global power redistribution within one control cycle, so that the expanded heating array still meets the temperature field non-uniformity requirements.

[0051] Step S8: After the heat preservation is completed, the intelligent controller controls each module to gradually reduce its output power according to the cooling rate set in the target temperature process curve. When the temperature drops to the set threshold, the airflow microchannel valves in the intermediate heat insulation layer can be selectively opened to introduce cooling airflows such as compressed air to achieve controlled accelerated cooling. Once the component temperature drops to a safe range, the system stops heating and generates a digital heat treatment report containing data from the entire process.

[0052] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0053] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An adaptive, scalable, modular induction heating system, characterized in that, include: Multiple flexible induction heating modules, each of the flexible induction heating modules comprising: The flexible substrate is composed of a multi-layer composite structure including at least a working surface layer, an intermediate heat insulation layer and a backing layer. The working surface layer can generate elastic deformation when subjected to external pressure to conform to the complex curved surface of the component to be heated, and maintain the conformed curved surface shape after the pressure is removed. The induction coil is woven from multiple strands of Litz wire and is fixedly disposed between the intermediate heat insulation layer and the working surface layer. When the flexible substrate is in an unbent state, the induction coil is located on the bending neutral surface of the multilayer composite structure, so that when the flexible substrate bends, the inductance change rate of the coil remains within a preset threshold. The magnetic core is magnetically coupled to the induction coil and is composed of multiple separate magnetic chips connected to each other by flexible connectors, so that the magnetic core as a whole can change the shape of the magnetic circuit by following the bending of the flexible substrate. At least one strain sensor is used to detect the real-time bending curvature of the flexible induction heating module; Adjacent flexible induction heating modules are mechanically connected by at least one of flexible hinges, magnetic fasteners or elastic buckles set at the edge of the flexible substrate, and the electrical connection interfaces of power supply, communication and sensing signals integrated in the mechanical connection structure are connected simultaneously, thereby forming a continuous curved surface heating array that matches the shape and area of ​​the area to be heated. A distributed temperature sensing network, comprising multiple fiber optic temperature sensors or thin-film thermocouples, is arranged on the working surface of each flexible induction heating module and independently in the heat-affected zone, for real-time acquisition of temperature signals at each measurement point with a spatial resolution no less than a preset value. The intelligent controller is communicatively connected to the distributed temperature sensing network, the strain sensors of each flexible induction heating module, and their electrical interfaces; the intelligent controller includes: The temperature field reconstruction unit is used to receive the multi-point temperature signals, combine the spatial coordinates of each measurement point and execute a spatial interpolation algorithm to generate a three-dimensional temperature field distribution of the loading area in real time. The module location identification and mapping unit is used to automatically identify the address identifiers of each access module and their adjacent relationships through the communication handshake protocol, and to construct the topology diagram of the heating array. The power distribution calculation unit is used to compare the generated three-dimensional temperature field distribution with the target temperature process curve set by the user, obtain the temperature deviation and change trend of the corresponding local area of ​​each flexible induction heating module, and obtain the corresponding real-time curvature; based on the pre-calibrated and stored curvature-electromagnetic coupling efficiency mapping relationship, determine the induction heating efficiency correction factor of each module; adopt a dual closed-loop control algorithm including thermal inertia feedforward compensation and curvature compensation to generate an independent dynamic target power command for each flexible induction heating module to compensate for the difference in electromagnetic coupling efficiency and local heat capacity change caused by the change in the surface fitting state, and control the temperature field non-uniformity of the heating array within ±5℃; An scalable power supply and communication bus system includes a modular power supply unit and a communication bus; the modular power supply unit is configured to automatically allocate power according to the number of currently connected flexible induction heating modules; the communication bus supports hot-swapping and is used to transmit power commands and sensing data; when any flexible induction heating module is connected or removed, the intelligent controller completes module identification and power allocation recalculation through the communication bus in the first instance.

2. The adaptive, scalable, modular induction heating system according to claim 1, characterized in that, The power distribution calculation unit of the intelligent controller uses a dual closed-loop control algorithm that includes thermal inertia feedforward compensation and curvature compensation to generate the target power command for the i-th flexible induction heating module in the following manner: Calculate temperature deviation and the rate of change of deviation ,in Let T be the target temperature at the location of the i-th module at the current time t. i (t) represents the measured temperature at that location; Call the preset equivalent heat capacity parameter C of the i-th module i and thermal inertia time constant Calculate the thermal inertia feedforward power component ,in The rate of change of the target temperature over time; Based on the real-time bending curvature k obtained from the strain sensor of the i-th module i The induction heating efficiency correction factor corresponding to the current curvature is obtained by looking up a table from the curvature-electromagnetic coupling efficiency mapping relationship. The factor is defined as ,in For curvature k i The measured coupling efficiency value is as follows. Reference coupling efficiency when attaching a flat panel; Calculate the feedforward power component after curvature correction ; The command power P is generated according to the following formula. cmd,i : Among them, K p K i K d The proportional, integral, and derivative control gains are respectively, and the intelligent controller adjusts at least the integral gain K based on the position of the i-th module in the heating array topology and its temperature coupling coefficient with adjacent modules. i Online adaptive adjustments are made to give modules located at the array edge or in areas with significant heat sink effects higher integral action strength.

3. The adaptive and scalable modular induction heating system according to claim 1, characterized in that, At least some of the fiber Bragg grating temperature sensors in the distributed temperature sensing network are embedded or attached to the working surface of the working layer on the side facing the component to be heated in an array with equal or non-equal spacing. The signal conditioning unit processes the original temperature signal through a weighted least squares filtering algorithm to suppress measurement noise and eliminate singular temperature values ​​caused by module splicing gaps.

4. The adaptive and scalable modular induction heating system according to claim 1, characterized in that, The flexible substrate has several airflow microchannels in the middle heat insulation layer. These airflow microchannels are connected to an external compressed air source and are used to introduce airflow during the heating or cooling stages to accelerate local temperature regulation or form a protective atmosphere.

5. The adaptive and scalable modular induction heating system according to claim 2, characterized in that, The curvature-electromagnetic coupling efficiency mapping relationship is pre-calibrated and stored in the intelligent controller in the following manner: In offline mode, a single flexible induction heating module is sequentially attached to test blocks with different standard curvature radii, the same input power is applied, and the heat or heating rate reached on the surface of the test block is measured to establish a correspondence table between curvature and coupling efficiency correction factors; in the power distribution calculation unit, for the actual bending curvature between curvature data points in the correspondence table, linear interpolation or polynomial interpolation is used to obtain the corresponding correction factor.

6. The adaptive, scalable, modular induction heating system according to claim 1, characterized in that, Each flexible induction heating module also integrates a non-volatile memory, which stores the module's unique identification code and the factory-calibrated equivalent heat capacity parameter C. i Thermal inertia time constant The module also displays the electromagnetic coupling characteristic curves under the reference plane. When the module is connected to the system through the electrical connection interface, the intelligent controller automatically reads these parameters to initialize the relevant control parameters in the power distribution calculation unit.

7. The adaptive, scalable, modular induction heating system according to claim 1, characterized in that, The modular power unit in the scalable power and communication bus system includes a DC bus system and multiple DC / AC inverter modules. Each DC / AC inverter module provides high-frequency AC power to a group of flexible induction heating modules. The intelligent controller achieves independent power regulation of each flexible induction heating module by adjusting the DC bus voltage or the switching duty cycle of each inverter module.

8. The adaptive, scalable, modular induction heating system according to claim 1, characterized in that, The intelligent controller also includes a process recording and traceability unit, which records the real-time power, measured temperature, bending curvature and control parameters of each flexible induction heating module at a frequency of not less than 1Hz throughout the heat treatment process, and generates a searchable and replayable digital heat treatment report to support process optimization and quality traceability.

9. An adaptive, scalable, modular induction heating temperature control method based on the system described in any one of claims 1 to 8, characterized in that, Includes the following steps: Step S1: Based on the actual shape and size of the repair area of ​​the complex component to be heated, select the required number of flexible induction heating modules, and splice the modules into a continuous curved surface heating array covering the repair area and the heat-affected zone through the mechanical connection structure and integrated electrical interface, and arrange the sensors of the distributed temperature sensing network in place. Step S2: The system is powered on. The intelligent controller sends a query command through the communication bus to automatically identify the number of connected flexible induction heating modules, the address code of each module, the relative position, and the thermal parameters pre-stored in each module, and constructs the initial array topology and thermal model. Step S3: Input or call the target temperature process curve that matches the repair layer material and substrate into the intelligent controller through the human-machine interface. The curve at least defines the heating rate R. up Insulation temperature T hold Insulation time t hold and cooling rate R down ; Step S4: Start the heating process. The intelligent controller acquires the temperature data of the distributed temperature sensing network and the bending curvature data of the strain sensors of each module in real time, and continuously generates the three-dimensional temperature field of the heating area through the temperature field reconstruction unit. Step S5: The power distribution calculation unit, based on the deviation between the current three-dimensional temperature field and the target temperature process curve, and in conjunction with the equivalent heat capacity parameter C of each flexible induction heating module, i Thermal inertia time constant Induction heating efficiency correction factor corresponding to real-time curvature The target power command for each module is calculated periodically and sent. Step S6: During the heating phase, if the actual temperature change rate of a certain area is detected to be lower or higher than the preset rate, or if the local heat sink effect exceeds the preset range due to the structure on the back of the component, the intelligent controller actively adjusts the power command allocation of the affected module and its adjacent modules, and synchronously updates the correction factor. The computational basis is used to maintain the uniformity of the temperature field across the entire array; Step S7: When it is necessary to expand the coverage area during the heating process or when the heating area is insufficient, a new flexible induction heating module is connected to the edge of the heating array. The intelligent controller automatically identifies the new module, updates the array topology, incorporates the new module into the temperature field reconstruction and power distribution calculation, and completes the global power redistribution within one control cycle, so that the expanded heating array continues to meet the requirements of temperature non-uniformity. Step S8: After the heat preservation is completed, the intelligent controller controls the output power of each module according to the cooling rate of the target temperature process curve, and optionally introduces cooling airflow through the airflow microchannel to achieve controlled cooling.

10. The adaptive, scalable, modular induction heating temperature control method according to claim 9, characterized in that, In step S5, the power allocation calculation unit calculates the target power command P of the i-th module. cmd,i The specific method is as follows: Among them, e i (t)=T target (t)-T i (t) represents the temperature deviation, T target (t) represents the target temperature at time t for the location corresponding to the i-th module. i (t) represents the measured temperature; C i and These are the equivalent heat capacity parameters and thermal inertia time constant obtained by the i-th module through self-identification, respectively; To determine the real-time bending curvature k of the i-th module i The induction heating efficiency correction factor is determined by looking up a table and interpolating. Furthermore, in step S6, when the intelligent controller determines that the temperature in a certain area deviates due to changes in local heat dissipation conditions, it also dynamically adjusts the integral gain K. i The adjustment amount is calculated based on the contribution of adjacent modules to the heat flow of this area.

Images