Power supply control method, heating device and product

Abstract

The invention provides a power supply control method, a heating device and a product, and relates to the technical field of power supply control, and the method comprises the steps: dividing a graphene heating film into a plurality of regions, and monitoring the real-time temperature data of each region; the resistance change rate of each area is calculated according to the real-time temperature data, an impedance distribution diagram is constructed according to the resistance change rate, and the control voltage of each area is adjusted based on the impedance distribution diagram and a preset rule. The accuracy of temperature control of the graphene heating film can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power supply control, in particular to a power supply control method, a heating device and a product. BACKGROUND

[0002] As a two-dimensional material composed of single-layer carbon atoms, graphene has shown great application potential in many fields due to its unique electronic structure and excellent physical and chemical properties. Among them, graphene heating film has been widely used in many fields such as heating, medical care, industrial heating, etc. due to its high heating efficiency, uniform heating, fast response speed and good flexibility. In the actual application of graphene heating film, power supply control is a key link. Precise power supply control not only ensures the stable and efficient work of graphene heating film, but also effectively prolongs its service life, and meets the diversified needs of temperature in different scenarios.

[0003] In related technologies, a temperature feedback control method is adopted, specifically: a plurality of temperature sensors are arranged on the graphene heating film to collect real-time temperature information on the surface of the heating film, and the collected temperature data is transmitted to a controller. The controller compares the real-time temperature with a preset temperature value. If the real-time temperature is lower than the preset temperature, the power supply voltage is increased to increase the heating power; if the real-time temperature is higher than the preset temperature, the power supply voltage is reduced to reduce the heating power, so as to realize rough adjustment of the temperature of the graphene heating film.

[0004] In fact, the resistance of the graphene heating film will change with the change of temperature, and the resistance change of different regions may be different. It is difficult to accurately grasp the real heating state of each region only according to the temperature data, which leads to inaccurate power supply control and easy occurrence of local overheating or overcooling, affecting the overall performance and service life of the heating film. SUMMARY

[0005] In order to improve the accuracy of temperature control of the graphene heating film, the present application provides a power supply control method, a heating device and a product.

[0006] In a first aspect, the present application provides a power supply control method, which adopts the following technical solution: A power supply control method, comprising the following steps: Divide the graphene heating film into a plurality of regions and monitor the real-time temperature data of each region; According to the real-time temperature data, calculate the resistance change rate of each region, construct an impedance distribution map according to the resistance change rate, and adjust the control voltage of each region based on the impedance distribution map and a preset rule.

[0007] The application divides the graphene heating film into multiple regions, and can independently monitor the temperature of each region. Since different regions may have temperature differences due to factors such as heat dissipation conditions, heating power distribution, etc. in actual use, the application can avoid the phenomenon of local overheating or overcooling when the whole is controlled uniformly. Then, the application calculates the resistance change rate of each region according to the real-time temperature data, and then constructs an impedance distribution map, and adjusts the control voltage in combination with the preset rules. The resistance change rate reflects the change of the electrical characteristics of the heating film at different temperatures, and the impedance distribution map directly presents the resistance state of the whole heating film. According to these information, the control voltage is dynamically adjusted, which can realize accurate control of the temperature of each region.

[0008] The application can timely find the uneven heating condition by monitoring the real-time temperature data of each region, and analyze the causes of temperature difference by using resistance change rate and impedance distribution map. It may be due to local material defects, poor contact or uneven heat dissipation, etc. Then, the control voltage is adjusted according to the preset rules, and the control voltage is adjusted according to the actual temperature requirement of each region, realizing the on-demand distribution of electric energy, and avoiding the situation that part of the region overheats and wastes electric energy when the whole heating film is uniformly powered, and part of the region cannot meet the demand. Improve user experience.

[0009] Optionally, the method further comprises: Obtaining user desired temperature data, calculating temperature deviation according to user desired temperature data and real-time temperature data, and calculating temperature deviation change rate based on temperature deviation; Input the temperature deviation and the temperature deviation change rate into the PID controller to obtain the adjustment rate of the control voltage.

[0010] The application obtains user desired temperature data and uses it as the target value of temperature control, so that the whole temperature control system is developed around the actual needs of the user. Compared with the traditional method of controlling only according to real-time temperature data, the application can more accurately adjust the temperature of the environment where the graphene heating film is located to the level desired by the user, and meet the individualized requirements of different users in different scenarios.

[0011] A PID controller has three control elements: proportional, integral, and derivative. The integral element accumulates temperature deviations and continuously adjusts the control voltage over time to eliminate minor temperature deviations in the steady-state system. Even if various disturbances (such as slow changes in ambient temperature or minor fluctuations in the heating film's performance) cause a difference between the actual and desired temperatures, the integral element still functions to gradually bring the actual temperature closer to the desired temperature, thereby improving the accuracy of temperature control. This application calculates the rate of change of temperature deviation based on the temperature deviation and inputs it into the PID controller, enabling the controller to promptly sense temperature change trends. The derivative element adjusts the control voltage in advance based on the rate of change of temperature deviation, acting as a pre-regulatory element. When the rate of change of temperature deviation is large, indicating a rapid temperature rise or fall, the derivative element rapidly increases or decreases the adjustment rate of the control voltage, accelerating the system's response speed and minimizing overshoot or undershoot. This application, by calculating the temperature deviation and its rate of change in real time and using the PID controller for dynamic adjustment, can quickly adapt to these changes, adjust the control voltage promptly, and maintain temperature stability. Regardless of changes in the external environment, the system can restore the temperature to the user's expected range in a short time, improving the system's adaptability and robustness.

[0012] Different users have different sensitivities and preferences for temperature. This application can meet users' personalized needs by acquiring their desired temperature data. Users can freely set their desired temperature based on their physical condition, clothing, and other factors. This application will precisely control the temperature according to the user's requirements, providing a more personalized service.

[0013] Optionally, the method further includes: Each region of the graphene heating film is treated as a node in a distributed system. When the real-time temperature data of a certain node does not meet the set temperature range, the node sends a temperature compensation request containing the compensation requirement value to the adjacent nodes. After receiving a temperature compensation request, a neighboring node compares its own temperature data with the target temperature data. If its own temperature data is lower than the target temperature data, it adjusts its own temperature data according to the target temperature data.

[0014] When the real-time temperature data of a node does not conform to the set temperature range, the node will send a temperature compensation request to neighboring nodes. Upon receiving the request, if the neighboring nodes' own temperature is lower than the target temperature, they will adjust their own temperature data, which can quickly correct local temperature anomalies and minimize the occurrence of local overheating or undercooling.

[0015] This application treats each region as an independent node. When a node malfunctions (such as sensor failure or circuit fault) causing abnormal temperature data, that node will only send compensation requests to neighboring nodes, without affecting the operation of the entire system. Neighboring nodes respond according to their own situations, and other unaffected nodes can continue to operate normally. The fault isolation mechanism adopted in this application can prevent the spread of faults, improve the system's fault tolerance, and enhance system stability. The compensation requests and responses between nodes based on temperature conditions enable on-demand heat distribution. Nodes with lower temperatures request heat compensation from neighboring nodes, thus avoiding overheating of already high-temperature areas and reducing unnecessary energy consumption.

[0016] Optionally, when adjacent nodes cannot meet the temperature compensation request, a secondary request is sent to nodes that are not directly adjacent but have a temperature control margin, and the optimal combination of cooperative nodes is selected through a path planning algorithm.

[0017] When neighboring nodes, due to their own temperatures being within a reasonable range or limited self-regulation capabilities, cannot fulfill temperature compensation requests, a secondary request is sent to nodes that are not directly adjacent but have temperature control margins. This breaks the limitation of relying solely on neighboring nodes for compensation, expanding the scope of temperature compensation and enabling the acquisition or transfer of heat from a wider area, thereby more effectively solving localized temperature anomalies. The path planning algorithm selects the optimal combination of cooperating nodes based on the location, temperature data, and temperature control margins of each node, ensuring heat is transferred along the most efficient path, minimizing excessive heat loss during transmission, and achieving precise temperature regulation of the target area.

[0018] Optionally, the method further includes: The impedance distribution map is extended into a three-dimensional impedance map that includes a time dimension. The spatial propagation law of the resistance change rate is identified through the three-dimensional impedance map. Based on the spatial propagation law, abnormal regions of the graphene heating film are identified. The influence of the abnormal regions on the remaining regions is calculated based on the three-dimensional impedance map. The affected regions are determined based on the influence degree. A reverse compensation voltage is applied to the affected regions according to the influence degree.

[0019] This application extends the impedance distribution map into a three-dimensional impedance map that includes a time dimension, thereby tracking its impedance changes at different points in time. Changes in resistance are often closely related to the performance state of the heating film; for example, when problems such as localized damage, poor contact, or material aging occur, the resistance will change accordingly. Through the three-dimensional impedance map, this application can comprehensively and dynamically monitor the resistance changes of the entire heating film, providing a rich data foundation for accurately identifying abnormal areas.

[0020] This application utilizes three-dimensional impedance mapping to identify the spatial propagation patterns of resistance change rates, enabling a deeper understanding of the diffusion methods and paths of anomalies within the heating film. Different causes of anomalies may lead to different propagation patterns. For example, resistance changes caused by localized overheating may diffuse to surrounding areas via heat conduction, while resistance changes caused by circuit faults may propagate along the circuit connection direction. By analyzing these patterns, this application can more accurately determine the origin and affected area of ​​anomalies, thereby precisely locating the abnormal region.

[0021] This application calculates the impact of anomaly regions on the remaining regions based on three-dimensional impedance maps, enabling a quantitative determination of the influence of anomaly regions on the surrounding normal regions. By calculating the degree of impact, this application can clearly understand the differences in the impact of anomaly regions on the remaining regions at different locations. The degree of impact on the remaining regions at different locations may vary; some regions may be severely affected, leading to significant changes in parameters such as temperature and current, while others may be less affected. By quantifying the degree of impact, this application can classify the remaining regions into different impact levels, allowing for different treatment measures to be taken for regions of different levels, thereby improving the targeting and effectiveness of compensation.

[0022] This application determines the affected area based on calculated impact levels, which can minimize blind compensation, improve the utilization efficiency of compensation resources, and reduce unnecessary energy consumption and system load. By applying a reverse compensation voltage, this application can effectively improve the overall performance of the heating film and enhance the accuracy and stability of temperature control.

[0023] Optionally, applying a reverse compensation voltage to the affected area according to the degree of influence includes: Using the abnormal region as the root node, the affected region is divided into multi-level child nodes according to the heat conduction path. A structure tree is constructed using the root node and multi-level child nodes, and the hierarchical depth of the structure is set according to the heat diffusion time constant. The weights of the connecting edges between the i-th and j-th nodes are set based on the equivalent thermal conductivity and temperature difference between the i-th and j-th nodes in the tree structure and the target temperature data. Traverse the tree structure from bottom to top, aggregating the temperature control requirements of child nodes layer by layer, including: The compensation voltage at the leaf node is calculated using the rate of change of resistance predicted by the three-dimensional impedance diagram. Based on the weights of the connection edges between low-level and high-level nodes and the compensation voltage of the leaf nodes, a weighted summation algorithm is used to calculate the first compensation amount. The second compensation amount is set according to the temperature response delay time of the high-level nodes. The sum of the first and second compensation amounts is used as the compensation voltage of the high-level nodes.

[0024] This application uses the anomalous region as the root node and divides the affected area into multi-level child nodes based on the heat conduction path to construct a structure tree. Simultaneously, it sets the level depth according to the heat diffusion time constant, which can accurately reflect the heat propagation process and impact range within the graphene heating film. Different levels of child nodes represent areas affected by the anomalous region to varying degrees, allowing for more targeted application of compensation measures. By adopting this scheme, this application can improve the accuracy and effectiveness of compensation, achieving more efficient temperature control.

[0025] This application sets the weights of the connecting edges based on the equivalent thermal conductivity, temperature difference, and target temperature data between nodes in the tree structure, fully considering the physical characteristics of heat transfer and the goal of temperature control, and can more accurately describe the heat transfer relationship and compensation requirements between nodes.

[0026] This application first traverses the tree structure from bottom to top and aggregates the temperature control requirements of child nodes layer by layer. It uses the resistance change rate predicted by the three-dimensional impedance diagram to calculate the compensation voltage of the leaf nodes. Then, based on the connection edge weights and the compensation voltage of the leaf nodes, a weighted summation algorithm is used to calculate the first compensation amount. The second compensation amount is set according to the temperature response delay time of the higher-level nodes. Finally, the compensation voltage of the higher-level nodes is obtained. By comprehensively considering various factors such as resistance change, heat transfer and temperature response delay, the required compensation voltage of each node can be accurately calculated, thereby achieving accurate temperature compensation.

[0027] Different graphene heating films may have different shapes, sizes, and layouts, resulting in variations in heat conduction paths and heat distribution. This application constructs a structure tree based on heat conduction paths, enabling it to adapt to heating films with various structures. Regardless of whether the heating film is a regular rectangle or an irregular shape, nodes can be divided and weights set by analyzing its heat conduction characteristics, thereby achieving effective temperature compensation.

[0028] Optionally, when there are conflicting requests among child nodes at the same level, nodes along the graphene lattice structure direction receive higher priority, while requests from child nodes outside the lattice direction are executed through a voting mechanism.

[0029] Optionally, if the temperature deviation of a certain level child node fails to meet the set temperature range multiple times consecutively, the child node whose temperature deviation fails to meet the set temperature range multiple times consecutively will be merged into the next level child node.

[0030] Secondly, this application provides a heating device, which adopts the following technical solution: A heating device, wherein the heating device employs the power supply control method as described in the first aspect during heating, comprising: The data acquisition module is used to divide the graphene heating film into multiple regions and monitor the real-time temperature data of each region. The voltage adjustment module is communicatively connected to the data acquisition module. It is used to calculate the resistance change rate of each region based on real-time temperature data, construct an impedance distribution map based on the resistance change rate, and adjust the control voltage of each region based on the impedance distribution map and preset rules.

[0031] Thirdly, this application provides a product that adopts the following technical solution: A product comprising a heating device as described in the second aspect, or the product employing a power supply control method as described in the first aspect.

[0032] In summary, this application includes at least one of the following beneficial technical effects: 1. This application divides the graphene heating film into multiple regions, enabling independent temperature monitoring for each region. Since different regions may experience temperature differences in actual use due to factors such as heat dissipation conditions and heating power distribution, this application can minimize localized overheating or undercooling that can occur during unified overall control.

[0033] 2. This application calculates the rate of resistance change in each region based on real-time temperature data, thereby constructing an impedance distribution diagram, and then adjusts the control voltage according to preset rules. The rate of resistance change reflects the change in the electrical characteristics of the heating film at different temperatures, while the impedance distribution diagram visually presents the resistance state of the entire heating film. By dynamically adjusting the control voltage based on this information, precise temperature control of each region can be achieved.

[0034] 3. This application monitors real-time temperature data in each area to promptly detect uneven heating. It analyzes the causes of temperature differences using resistivity change rate and impedance distribution diagrams, identifying potential issues such as localized material defects, poor contact, or uneven heat dissipation. Then, it adjusts the control voltage according to preset rules and the actual temperature requirements of each area, achieving on-demand power distribution. This avoids situations where some areas overheat and waste energy while others underheat and fail to meet requirements when the entire heating film is powered uniformly, thus improving the user experience. Attached Figure Description

[0035] Figure 1 This is a flowchart of Embodiment 1 of this application; Figure 2 This is a flowchart of Embodiment 2 of this application; Figure 3 This is a flowchart of Embodiment 3 of this application. Detailed Implementation

[0036] The following combination Figures 1 to 3 This application will be described in further detail.

[0037] Example 1: This example discloses a power supply control method, referring to... Figure 1 The method includes: S11 data acquisition, S12 voltage adjustment. The execution process of each step in this embodiment is as follows: S11 Data Acquisition: In this embodiment, the graphene heating film is divided into multiple regions based on its location. For example, based on the different positions of the graphene heating film in the cushion, it can be divided into a central region, a transition region, and an edge region. In other embodiments, the regions can also be divided according to the application scenario and requirements.

[0038] This embodiment uses software algorithms to logically divide the area. Specifically, by establishing a virtual area model in the control system, the entire area of ​​the heating film is mapped onto the software interface, and it is divided into multiple virtual areas according to preset division rules.

[0039] This embodiment uses a distributed temperature sensor array to monitor the real-time temperature data of each region of the graphene heating film.

[0040] In another embodiment of this application, temperature sensors are reasonably arranged in each divided area. For a small area, a sensor can be placed at the center of the area; for a large area, multiple sensors are evenly distributed, and the representative temperature of the area is obtained by taking the average or weighted average.

[0041] In other embodiments, the nano-silver wire temperature sensor can be embedded in the fabric layer of clothing or other materials to reduce tactile discomfort.

[0042] With voltage adjustment (S12), the resistance of graphene changes with temperature, and its resistance-temperature characteristics can usually be determined experimentally. Generally, within a certain temperature range, there is a functional relationship between the resistance of graphene and temperature, such as a linear or nonlinear relationship. This embodiment establishes a resistance model of the graphene heating film at different temperatures through preliminary experiments, i.e., a table or calculation model showing the correspondence between resistance values ​​and temperature. In this embodiment, the relationship between the resistance value and temperature satisfies the following calculation model:

[0043] in, The resistance value at temperature T; Reference temperature The resistance value at that time; The temperature coefficient of resistance of graphene is given by a value of [value missing]. .

[0044] The table showing the relationship between resistance and temperature can be obtained by discretizing the above calculation model.

[0045] Based on the real-time temperature data collected from each region, the resistance value of each region at the current temperature is calculated using the established calculation model. The resistance value of each region in the initial state (such as when the heating film is first powered on) is also obtained. The resistance change rate of each region is calculated according to the formula for the resistance change rate. The resistance change rate reflects the degree to which the resistance of each region of the graphene heating film changes with temperature.

[0046] The formula for calculating the rate of change of resistance is as follows: Rate of change of resistance = (Resistance value of a certain area under real-time temperature data - Resistance value of the area under initial conditions) ÷ Resistance value of the area under initial conditions × 100% Using any point on the graphene heating film as the origin, a Cartesian coordinate system is constructed with the length direction of the graphene heating film as the horizontal axis and the width direction of the graphene heating film as the vertical axis. The calculated resistance change rate of each region is mapped to the corresponding coordinate position in the Cartesian coordinate system to obtain the impedance distribution diagram. In this embodiment, since the power supply is a DC power supply, the inductive reactance of the graphene heating film is equal to zero and the capacitive reactance is infinite. Therefore, in this embodiment, the impedance distribution diagram is simplified to a resistance distribution diagram.

[0047] In the impedance distribution diagram, this embodiment uses red to represent areas with a large rate of change in resistance and blue to represent areas with a small rate of change in resistance. The intensity of the color reflects the magnitude of the rate of change in resistance.

[0048] To more accurately adjust the temperature of each region, this embodiment also adjusts the control voltage of each region based on the impedance distribution diagram and preset rules, as follows: The regional impedance gradient and overall impedance variance are calculated based on the impedance distribution map. The calculation model for the regional impedance gradient is as follows:

[0049] in, is the average of the absolute values ​​of the impedance difference between the i-th region and its adjacent regions, i.e., the impedance gradient of the i-th region; n is the number of adjacent regions of the i-th region; Let be the impedance of the i-th region; Let be the impedance of the j-th region.

[0050] The calculation model for the overall impedance variance is as follows:

[0051] in, The overall impedance variance is denoted by m; m is the total number of zones. Let be the impedance of the i-th region; This represents the average impedance across all regions.

[0052] This embodiment pre-sets three levels of rules: basic adjustment rules, balance adjustment rules, and global adjustment rules, as shown in Table 1.

[0053] Table 1

[0054] In other embodiments, the control voltage can also be adjusted by threshold judgment and fixed step size through a pre-established mapping relationship between regional impedance values ​​and control voltage, as follows: In a laboratory environment, temperature-impedance calibration is performed on each region, and the reference impedance corresponding to the target temperature data and the allowable impedance fluctuation range are recorded. Based on the deviation between the impedance and the reference value, five intervals are divided, each corresponding to a fixed voltage adjustment action. In this embodiment, the voltage adjustment actions corresponding to different impedance fluctuation conditions are shown in Table 2.

[0055] Table 2 impedance voltage adjustment action [Z < Z0 x (1 - 2k)] adjusting the voltage to 110% of the rated voltage [Z0 x (1 - 2k) < Z < Z0 x (1 - k)] Every 10 minutes increase 1 volt until the impedance is in Z0 x (1 - k) < Z < Z0 x (1 + k) [Z0 x (1 - k) < Z < Z0 x (1 + k)] not adjusting [Z0 x (1 + k) < Z < Z0 x (1 + 2k)] Every 10 minutes decrease by 1 volt until impedance is in Z0 x (1 - k) < Z < Z0 x (1 + k) [Z > Z0 x (1 + 2k)] To 80% of the rated voltage, if the impedance is still greater than Z0x (1+2k) after 10s, power off processing is performed Where Z is the real-time impedance value of a certain region of the graphene heating film; Z0 is the calibration value, which is 100 ohms, and k is 0.1-0.15.

[0056] In other embodiments, after the voltage adjustment step S12, the method further includes: The system acquires the user's desired temperature data and calculates the temperature deviation based on the user's desired temperature data and the real-time temperature data. The temperature deviation is equal to the difference between the user's desired temperature data and the real-time temperature data. If the temperature deviation is greater than zero, it means that the actual temperature is lower than the desired temperature and the voltage needs to be increased. If the temperature deviation is less than zero, it means that the actual temperature is higher than the desired temperature and the voltage needs to be decreased. If the temperature deviation is equal to zero, it means that the actual temperature is equal to the desired temperature and the voltage needs to be maintained.

[0057] The rate of change of temperature deviation is calculated based on the temperature deviation itself. The formula for calculating the rate of change of temperature deviation is as follows: Temperature deviation change rate = (current temperature deviation - temperature deviation calculated in the previous acquisition cycle) ÷ time interval; The time interval is equal to the absolute difference between the timestamp of the previous collection cycle and the timestamp of the current collection cycle.

[0058] A temperature deviation rate greater than zero indicates that the temperature deviation is increasing, requiring a faster control voltage adjustment rate; a temperature deviation rate less than zero indicates that the temperature deviation is decreasing, requiring a slower voltage adjustment rate; a temperature deviation rate equal to zero maintains the current adjustment rate.

[0059] The temperature deviation and the rate of change of temperature deviation are input into the PID controller to obtain the adjustment rate of the control voltage. The calculation model of the PID controller output is as follows:

[0060] in, The voltage regulation rate has a range of -5 to 5V / s. When the calculated voltage regulation rate exceeds this range, the voltage regulation rate is forcibly set to either an upper or lower limit, depending on the value. For the distance setting from the upper and lower limits, choose the smaller distance; This is a proportionality coefficient, with a value ranging from 2.0 to 3.0. The temperature deviation at time t; for Temperature deviation at any time The time interval within the data acquisition cycle; This is the integral coefficient, with a value ranging from 0.05 to 0.2; These are the differential coefficients, with values ​​ranging from 0.3 to 0.8. Let be the rate of change of temperature deviation at time t; for The rate of change of temperature deviation at any given time.

[0061] Example 2: Refer to Figure 2 The difference between this embodiment and Embodiment 1 is that the method further includes: S21 sends a request to define each region of the graphene heating film as a node in the distributed system. When the real-time temperature data of a node does not meet the set temperature range, the node sends a temperature compensation request to the adjacent nodes.

[0062] The set temperature range can be a fixed value preset by the system, or it can be the user's desired temperature data. Alternatively, the system can initially use a preset temperature range and then gradually adjust it to the user's desired temperature data.

[0063] Taking the user's desired temperature range as an example, the process by which this node sends a temperature compensation request to its neighboring nodes is as follows: This node calculates the compensation requirement value, which is equal to the absolute difference between the user's expected temperature data and the real-time temperature data; it generates a request frame containing the compensation requirement value, which also includes the source node ID, the target neighbor node ID, and the request priority. The node then broadcasts the temperature compensation request to all first-level neighbor nodes.

[0064] S22 adjusts the temperature of adjacent nodes. After receiving a temperature compensation request, the adjacent node compares its own temperature data with the target temperature data (generally, the target temperature data is the upper limit of the set temperature range). If its own temperature data is lower than the target temperature data, it adjusts its own temperature data according to the target temperature data. That is, abnormal nodes whose real-time temperature data does not meet the set temperature range are heated through heat conduction from adjacent nodes.

[0065] If the temperature data itself is not lower than the target temperature data, a rejection response frame is returned.

[0066] S23 linkage adjustment: When all adjacent nodes cannot meet the temperature compensation request, a secondary request is sent to nodes that are not directly adjacent but have temperature control margin. The optimal combination of cooperative nodes is selected through a path planning algorithm, as follows: Using the abnormal node as the source point, calculate the shortest path weight of all nodes. The shortest path weight is equal to a multiple of the inverse of the physical distance between each node and the abnormal node. Use Dijkstra's or Floyd's algorithm to calculate the shortest path weight of all nodes to the abnormal node. The nodes corresponding to the shortest path weight are taken as the optimal cooperative node combination. The optimal cooperative node combination gradually compensates for the temperature loss of the abnormal node through heat conduction.

[0067] Example 3: Reference Figure 3 The difference between this embodiment and Embodiment 2 is that the method further includes: S31 determines the affected area and expands the impedance distribution map into a three-dimensional impedance map that includes a time dimension. Specifically, based on the Cartesian coordinate system of the impedance distribution map, the timestamp of the calculated resistance change rate is mapped to the three-dimensional spatial coordinate system with time as the vertical axis to obtain the three-dimensional impedance map.

[0068] Based on the dynamic evolution characteristics of the three-dimensional impedance map, the spatial propagation law is quantified through three core indicators: propagation rate, direction, and attenuation coefficient. The specific method is as follows: A specific region is selected, and the expansion distance of the spatial boundary of that region over time is tracked. The propagation rate is calculated as expansion distance ÷ expansion time. Experiments show that in the graphene heating film, the propagation rate along the lattice direction is 0.8-1.2 m / s, and perpendicular to the lattice direction is 0.3-0.5 m / s.

[0069] By analyzing the direction vectors of the expansion of the above regions using a vector clustering algorithm, the three directions with the highest frequency of occurrence are selected as the main propagation directions. Combined with the graphene lattice structure (such as the six symmetry axes of a honeycomb structure), the lattice-preferred propagation directions and non-lattice directions are marked.

[0070] Calculate the attenuation value of the resistance change rate along the propagation path in the above area. The attenuation coefficient = resistance change rate of the abnormal area ÷ resistance change rate at a distance d from the abnormal area. The attenuation coefficient is positively correlated with the propagation distance. For every 0.5cm increase in distance, the attenuation coefficient increases by 0.15-0.2 times.

[0071] The process of identifying abnormal regions in graphene heating films based on spatial propagation laws is as follows: Define the propagation characteristics of the abnormal region, including: setting an abnormal abrupt change threshold range for the rate of change of resistance to be less than... or greater than The abnormal propagation direction of the resistance change rate is set as the region where the propagation speed suddenly increases / decreases (e.g., from 10cm / s to 0.1cm / s). The period of the resistance change rate is not synchronized with the excitation frequency (e.g., the excitation frequency is 1kHz, but the region period is 500Hz).

[0072] Abnormal regions are marked on the 3D impedance diagram, for example, abnormal regions are marked in gray. The influence of the abnormal regions on the remaining regions is calculated based on the 3D impedance diagram. The calculation model for the influence is as follows:

[0073] in, This represents the degree of influence of the abnormal region on the j-th remaining region. This represents the change in resistance in the j-th remaining region; Let be the change in current density in the j-th remaining region; Let be the temperature change in the j-th remaining region; This is the reference value for the resistance in the normal region; This serves as a reference value for the current density in the normal region. This is the baseline value for the normal temperature range.

[0074] For the reference value of resistance in the normal region Using a high-precision resistance measuring instrument, multiple measurement points are selected within a normal area to measure their resistance values. The average of these measurements is then taken as the resistance value. .

[0075] For the reference value of current density in the normal region By using devices such as current probes or Hall effect sensors, the current is measured within a normal area, and the current density is calculated by combining this with information such as the cross-sectional area of ​​that area. Similarly, the average value from multiple measurement points is taken as the current density. .

[0076] For the reference value of normal zone temperature Temperature measurements are taken within the normal range using temperature sensors (such as thermocouples, infrared thermometers, etc.), and the average value is used as the mean. .

[0077] The affected areas are determined based on the degree of impact, and the remaining areas with an impact degree greater than 0.8 are marked as affected areas.

[0078] S32 applies a reverse voltage, and applies a reverse compensation voltage to the affected area according to the degree of influence, including: Using the abnormal region as the root node, the affected region is divided into multiple levels of child nodes according to the heat conduction path. In this embodiment, the child nodes include first-level child nodes and second-level child nodes, as detailed below: A first-level child node refers to the region that is directly in contact with the root node (such as adjacent regions with a distance of <1mm).

[0079] Second-level child nodes refer to areas indirectly affected by first-level child nodes (such as areas 1-3mm away).

[0080] A tree structure is constructed using a root node and multi-level child nodes. The hierarchical depth of the structure is set according to the thermal diffusion time constant. The calculation model for the hierarchical depth L is as follows:

[0081]

[0082] in, The normal propagation time from the anomalous area to the affected area is equal to the distance D from the geometric center of the anomalous area to the geometric center of the affected area divided by the propagation rate. The thermal diffusion time constant; The density of graphene; The specific heat capacity of graphene; It is the equivalent thermal conductivity.

[0083] Based on the equivalent thermal conductivity and temperature difference between the i-th and j-th nodes in the tree structure, and the target temperature data, the weights of the connecting edges between the i-th and j-th nodes are set. The calculation model for these weights is as follows:

[0084] in, Let be the weight of the edge connecting the i-th node and the j-th node; Let be the equivalent thermal conductivity from node i to node j; It is the sum of the thermal conductivity of all the child nodes of the i-th node; Let be the temperature difference between the i-th node and the j-th node; is the target temperature data; exp(·) is the exponential operation.

[0085] Traverse the tree structure from bottom to top, aggregating the temperature control requirements of child nodes layer by layer, including: The compensation voltage at the leaf node is calculated using the rate of change of resistance predicted by the three-dimensional impedance diagram. The process is as follows: Extract the impedance data Z0(t), Z1(t), ..., Z9(t) of the leaf node over the past 10 time steps from the three-dimensional impedance diagram.

[0086] Based on the above impedance data, a linear regression algorithm is used to fit the impedance change trend. The linear regression formula is as follows:

[0087] in, Here are the impedance data at time t; a is the linear slope; b is the intercept; both are solved using the least squares method.

[0088] The predicted impedance is calculated using the linear regression formula, the predicted rate of change of resistance is calculated based on the predicted impedance, and the compensation voltage of the leaf node is calculated based on the predicted rate of change of resistance.

[0089]

[0090] in, This is the compensation voltage for the leaf nodes; This is the rated voltage, which can be either 24V or 36V. This represents the predicted rate of change in resistance. is the maximum allowable rate of change of resistance; f is the compensation coefficient, with a value of 0.8; It is a symbolic function.

[0091] Based on the weights of the edges connecting lower-level and higher-level nodes and the compensation voltage of the leaf nodes, a weighted summation algorithm is used to calculate the first compensation amount. A second compensation amount is set according to the temperature response delay time of the higher-level nodes. The sum of the first and second compensation amounts is taken as the compensation voltage of the higher-level nodes. The calculation model for the compensation voltage of the higher-level nodes is as follows:

[0092]

[0093] in, This is the compensation voltage for higher-level nodes; is the compensation voltage of the j-th low-level node; u is the second compensation amount; The rated voltage is 24V or 36V; h is the compensation coefficient, ranging from 0.05 to 0.08. Temperature response delay time for higher-level nodes; This is the maximum delay time; This is the symbol for the first compensation amount.

[0094] S33 handles conflicts. When there are conflicting requests between child nodes at the same level, child nodes along the graphene lattice structure direction receive higher priority. Specifically, the connection path between the child node and the root node is mapped to the graphene lattice direction. If the connection path of the child node is along the armchair direction, it is marked as a high-priority direction; if the connection path of the child node is along the serrated direction, it is marked as a low-priority direction.

[0095] Requests from amorphous child nodes are executed through a voting mechanism, specifically: the temperature weight of the amorphous child node is calculated based on the temperature difference, the resistance weight of the amorphous child node is calculated based on the resistance change rate, and the probability of the amorphous child node's request being executed is calculated using a weighted summation algorithm.

[0096] Temperature weighting The calculation model is as follows:

[0097] The temperature deviation between the real-time temperature data and the target temperature data of the amorphous direction sub-nodes; This is the maximum value among all temperature deviations.

[0098] Resistance weight The calculation model is as follows:

[0099] This represents the resistance change of the subnodes in the amorphous direction; It is the maximum value among all resistance changes.

[0100] Request Execution Probability The calculation model is as follows:

[0101] Each amorphous direction child node reveals either a support vote or a opposition vote based on the probability of the request being executable. If the number of support votes for a certain amorphous direction child node is greater than the number of opposition votes, and the probability of the request being executable is greater than 0.5, then the request of that amorphous direction child node is allowed to be executed.

[0102] S34 structural adjustment: When the temperature deviation of a certain level child node fails to meet the set temperature range multiple times consecutively, the child node whose temperature deviation fails to meet the set temperature range multiple times consecutively will be merged into the next level child node.

[0103] Example 4: This example discloses a heating device, which employs the aforementioned power supply control method during heating, including: The data acquisition module is responsible for dividing the graphene heating film into multiple independent regions. Then, using precision equipment such as thermistors and temperature sensors, the temperature of each region is monitored in real time, and the corresponding temperature data is collected.

[0104] The voltage adjustment module maintains a communication connection with the data acquisition unit. Based on the real-time temperature data collected from each region, it accurately calculates the rate of change of resistance in each region. Then, it plots an impedance distribution diagram based on these rates of change and flexibly adjusts the control voltage for each region according to this diagram and pre-set rules.

[0105] This embodiment employs an independently adjustable DC-DC converter. Each channel of the DC-DC converter corresponds to a partition electrode of the graphene heating film, and the partition boundary is formed into a high-resistance isolation band by laser etching.

[0106] If the graphene heating film is applied to clothing, cushions, and other items, then hot melt adhesive threads made of textile insulation material are used instead of laser etching to maintain the flexibility of the fabric. The graphene heating film and the textile substrate are integrated through a hot-pressing composite process, and the electrodes adopt a stretchable serpentine wiring design, with a resistance change rate of less than or equal to 5% after 1000 bends.

[0107] Example 5: This example provides a product that includes the heating device described above, or the product employs the power supply control method described above.

[0108] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A power supply control method, characterized in that, include: The graphene heating film was divided into multiple regions, and the real-time temperature data of each region was monitored. The resistance change rate of each region is calculated based on real-time temperature data. An impedance distribution map is constructed based on the resistance change rate. The control voltage of each region is adjusted based on the impedance distribution map and preset rules.

2. The power supply control method according to claim 1, characterized in that, The method further includes: Acquire user-expected temperature data, calculate temperature deviation based on user-expected temperature data and real-time temperature data, and calculate the rate of change of temperature deviation based on temperature deviation. The temperature deviation and the rate of change of temperature deviation are input into the PID controller to obtain the adjustment rate of the control voltage.

3. The power supply control method according to claim 2, characterized in that, The method further includes: Each region of the graphene heating film is treated as a node in a distributed system. When the real-time temperature data of a certain node does not meet the set temperature range, the node sends a temperature compensation request containing the compensation requirement value to the adjacent nodes. After receiving a temperature compensation request, a neighboring node compares its own temperature data with the target temperature data. If its own temperature data is lower than the target temperature data, it adjusts its own temperature data according to the target temperature data.

4. The power supply control method according to claim 3, characterized in that, When neighboring nodes cannot meet the temperature compensation request, a secondary request is sent to non-directly adjacent nodes that have a temperature control margin, and the optimal combination of cooperative nodes is selected through a path planning algorithm.

5. The power supply control method according to claim 3, characterized in that, The method further includes: The impedance distribution map is extended into a three-dimensional impedance map that includes a time dimension. The spatial propagation law of the resistance change rate is identified through the three-dimensional impedance map. Based on the spatial propagation law, abnormal regions of the graphene heating film are identified. The influence of the abnormal regions on the remaining regions is calculated based on the three-dimensional impedance map. The affected regions are determined based on the influence degree. A reverse compensation voltage is applied to the affected regions according to the influence degree.

6. The power supply control method according to claim 5, characterized in that, Applying a reverse compensation voltage to the affected area according to the degree of impact includes: Using the abnormal region as the root node, the affected region is divided into multi-level child nodes according to the heat conduction path. A structure tree is constructed using the root node and multi-level child nodes, and the hierarchical depth of the structure is set according to the heat diffusion time constant. The weights of the connecting edges between the i-th and j-th nodes are set based on the equivalent thermal conductivity and temperature difference between the i-th and j-th nodes in the tree structure and the target temperature data. Traverse the tree structure from bottom to top, aggregating the temperature control requirements of child nodes layer by layer, including: The compensation voltage at the leaf node is calculated using the rate of change of resistance predicted by the three-dimensional impedance diagram. Based on the weights of the connection edges between low-level and high-level nodes and the compensation voltage of the leaf nodes, a weighted summation algorithm is used to calculate the first compensation amount. The second compensation amount is set according to the temperature response delay time of the high-level nodes. The sum of the first and second compensation amounts is used as the compensation voltage of the high-level nodes.

7. The power supply control method according to claim 6, characterized in that, When there are conflicting requests from child nodes at the same level, nodes along the graphene lattice structure direction receive higher priority, while requests from child nodes outside the lattice direction are executed through a voting mechanism.

8. The power supply control method according to claim 6, characterized in that, If the temperature deviation of a certain level child node fails to meet the set temperature range multiple times consecutively, the child node with the consecutive temperature deviation failure to meet the set temperature range will be merged into the next level child node.

9. A heating device, wherein the heating device employs the power supply control method as described in any one of claims 1-8 during heating, characterized in that, The heating device also includes: The data acquisition module is used to divide the graphene heating film into multiple regions and monitor the real-time temperature data of each region. The voltage adjustment module is communicatively connected to the data acquisition module. It is used to calculate the resistance change rate of each region based on real-time temperature data, construct an impedance distribution map based on the resistance change rate, and adjust the control voltage of each region based on the impedance distribution map and preset rules.

10. A product characterized in that, The product includes the heating device as described in claim 9, or the product employs the power supply control method as described in any one of claims 1-8.

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