Multi-working-condition combined heating mode switching method and system for electric food warmer

Abstract

The invention relates to the technical field of electric food warmer heating control, and discloses an electric food warmer multi-working-condition combined heating mode switching system which comprises a warmer body, a partition resistance heating assembly, a thermal field collecting assembly, a high-temperature connecting base assembly, a switching driving assembly and a control assembly. The partition resistance heating assembly comprises a center heating branch, an annular main heating branch and an edge compensation heating branch. According to the invention, the control assembly judges the current cooking condition according to the pot bottom center area temperature parameter, the pot bottom edge area temperature parameter and the in-pot steam detection parameter, generates the corresponding target combined heating mode, and firstly reduces the power-on branch to the preset transition power when the mode changes; according to the method, the edge compensation heating branch is connected with the heating branch, then the connection relation and the power-on time sequence of the heating branches are controlled to be switched, and when the dry burning risk working condition is judged, verification recheck and protection control are executed through the edge compensation heating branch, so that the thermal field matching performance, the mode switching stability and the dry burning judgment accuracy are improved.

Description

Technical Field

[0001] This invention relates to the technical field of heating control for electric hot pots, specifically to a method and system for switching between multiple operating conditions and combined heating modes of an electric hot pot. Background Technology

[0002] Electric hot pots are a common type of electric heating appliance in home cooking, typically used for boiling, steaming, stewing, and keeping warm. The state of the food inside the pot, the liquid content, and the heating requirements of the pot bottom all change at different cooking stages. In particular, the heating rate and heat dissipation differ between the central area of ​​the pot bottom, the main heating area, and the edge areas. Therefore, in actual use, the heating settings of an electric hot pot usually need to be adjusted according to different cooking conditions to meet the corresponding cooking requirements.

[0003] Existing electric hot pots typically have a single resistance heating element at the bottom of the pot, or several heating zones, and control heating through mechanical speed settings, power adjustment circuits, timer programs, or thermostat start / stop mechanisms. While some solutions can achieve zoned heating, the connections and power supply methods of each heating zone are mostly pre-fixed. Control relies primarily on a single temperature parameter, simple timing logic, or overall heat level switching, lacking a combined assessment of the heating status of different areas of the pot bottom and the steam state inside the pot. This makes it difficult to adjust the heating mode specifically for different cooking stages.

[0004] Under the above structure, the connection relationship and power control method of the existing heating branches are relatively fixed, while the heat demand of the pot body on the central and edge areas of the pot bottom changes continuously during rapid preheating, continuous boiling, steaming, stewing and heat preservation. During use, it is easy for the pot bottom to heat up too quickly in some areas, the edge to not heat up enough, or the mode switching to fluctuate greatly. As a result, it is difficult to keep the heat field distribution of the pot bottom in line with the actual cooking conditions. At the same time, the existing solution relies on a single temperature anomaly or a single steam change signal to judge the dry burning state. It is easily affected by short-term fluctuations, thus affecting the cooking stability and safety of use. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for switching multiple heating modes in an electric hot pot, in order to solve the problems of existing electric hot pots being unable to accurately determine the current cooking conditions based on the heating state of different areas of the pot bottom and the steam state inside the pot, and to smoothly switch the combined heating modes of each heating branch accordingly, resulting in insufficient heat field matching, poor cooking stability, and low accuracy in judging dry burning.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a multi-condition combined heating mode switching system for electric hot pot, comprising a pot body, a zoned resistance heating component, a heat field acquisition component, a high-temperature connection base component, a switching drive component, and a control component. The partitioned resistance heating assembly is located at the bottom of the pot body and includes a central heating branch, a ring-shaped main heating branch, and an edge compensation heating branch, respectively corresponding to the central area of ​​the pot bottom, the main heating area of ​​the pot bottom, and the edge compensation area of ​​the pot bottom. The high-temperature connecting seat assembly is located outside the heating area at the bottom of the pot body. It includes a ceramic connecting base, multiple lead-out terminals mounted on the ceramic connecting base, and a heat-insulating partition between adjacent lead-out terminals. The central heating branch, the annular main heating branch, and the edge compensation heating branch are respectively connected to the corresponding lead-out terminals via high-temperature resistant transition conductive parts. The switching drive component is located in the non-heated area outside the high-temperature connector assembly and is electrically connected to each lead-out terminal. Under the control of the control component, the switching drive component changes the connection relationship and energizing sequence of the central heating branch, the ring main heating branch and the edge compensation heating branch. The thermal field acquisition component is connected to the pot body and outputs temperature parameters of the central area of ​​the pot bottom, temperature parameters of the edge area of ​​the pot bottom, and steam detection parameters inside the pot. The control component is electrically connected to the thermal field acquisition component and the switching drive component, respectively, and is used to receive temperature parameters of the center area of ​​the pot bottom, temperature parameters of the edge area of ​​the pot bottom, and steam detection parameters inside the pot, determine the current cooking condition, and output the target joint heating mode corresponding to the current cooking condition. The target joint heating mode includes the target power distribution relationship and branch drive mode corresponding to the center heating branch, the ring main heating branch, and the edge compensation heating branch. The target power distribution relationship is one or more of the power distribution ratio, power-on duration ratio, or duty cycle corresponding to each heating branch. The branch drive mode includes the connection relationship and power-on sequence of each heating branch. When the target combined heating mode is inconsistent with the currently executed combined heating mode, the control component first controls the input power of the heating branch that is currently energized to be reduced to a preset transition power, and then controls the switching drive component to change the connection relationship and energization sequence of each heating branch in order to establish the target combined heating mode. When the control component determines that the current cooking condition is a dry-burning risk condition, it first controls the edge compensation heating branch to run at a preset verification power for a preset verification time. Then, it verifies the dry-burning risk condition based on the temperature parameters of the center area of ​​the bottom of the pot, the temperature parameters of the edge area of ​​the bottom of the pot, and the state of steam in the pot. When the verification result shows that the pot is in a dry-burning state with insufficient liquid, it controls each heating branch to stop supplying power.

[0007] Preferably, the central heating branch, the annular main heating branch, and the edge compensation heating branch are each composed of one or more resistive heating sections; the branch driving modes include parallel high-power driving mode, series steady-state driving mode, edge compensation driving mode, and alternating pulse driving mode; The parallel high-power drive mode is to energize two heating branches in parallel; the series steady-state drive mode is to energize the central heating branch and the ring main heating branch in series; the edge compensation drive mode is to energize the edge compensation heating branch and the central heating branch or the ring main heating branch together; and the alternating pulse drive mode is to alternately conduct two heating branches according to a preset timing sequence.

[0008] Preferably, the thermal field acquisition component includes a center temperature sensor, an edge temperature sensor, and a steam state sensor; The center temperature sensor outputs the temperature parameters of the center area of ​​the bottom of the pot, the edge temperature sensor outputs the temperature parameters of the edge area of ​​the bottom of the pot, and the steam state sensor outputs the steam detection parameters inside the pot. The control component determines the steam appearance status parameters and the steam duration parameters based on the steam detection parameters inside the boiler.

[0009] Preferably, the control component determines the current cooking condition based on the temperature rise rate of the central region of the pot bottom, the temperature rise rate of the edge region of the pot bottom, the temperature difference between the central region and the edge region of the pot bottom, and the state of steam in the pot. The steam state inside the pot includes no steam state, initial steam state, and continuous steam state. The current cooking conditions include rapid preheating, continuous boiling, steaming, braising, heat preservation, and dry-burning risk conditions.

[0010] Preferably, the preset transition power is lower than the input power of the corresponding heating branch before switching.

[0011] Preferably, the ceramic connecting base is provided with heat-insulating partitions distributed along each lead-out terminal; the high-temperature resistant transition conductive element is one of a high-temperature resistant metal sheet, a high-temperature resistant braided conductor, or a high-temperature resistant elastic conductor.

[0012] Preferably, it also includes a branch electrical parameter acquisition unit; the branch electrical parameter acquisition unit is used to acquire the current parameters and voltage parameters of each heating branch, or to acquire the resistance parameters determined by the current parameters and voltage parameters of each heating branch; the control component determines the conduction state, normal load state, open circuit state, short circuit state or resistance drift state of each heating branch according to the electrical parameters of each heating branch.

[0013] Preferably, when the control component verifies the dry-burning risk condition, it determines whether the pot is in a state of liquid shortage and dry burning based on the changes in the temperature parameters of the central area of ​​the pot bottom, the temperature parameters of the edge area of ​​the pot bottom, and the state of steam appearance in the pot during the operation of the edge compensation heating branch at the preset verification power. Within the preset verification time, if the state of steam appearance in the pot remains without steam, and the temperature parameters of the central area of ​​the pot bottom and the temperature parameters of the edge area of ​​the pot bottom continue to rise relative to the start time of verification, it is determined that the pot is in a state of liquid shortage and dry burning.

[0014] This invention also provides a method for switching between multiple operating conditions and combined heating modes of an electric hot pot, applied to the aforementioned system for switching between multiple operating conditions and combined heating modes of an electric hot pot, comprising the following steps: S1. Collect temperature parameters of the central area of ​​the bottom of the pot, temperature parameters of the edge area of ​​the bottom of the pot, and steam detection parameters inside the pot. S2. Determine the state of steam in the pot based on the steam detection parameters, and determine the current cooking conditions based on the temperature parameters of the center area of ​​the bottom of the pot, the temperature parameters of the edge area of ​​the bottom of the pot, and the state of steam in the pot. S3. Generate a corresponding target combined heating mode based on the current cooking conditions. The target combined heating mode includes the target power distribution relationship and branch driving mode corresponding to the central heating branch, the ring main heating branch and the edge compensation heating branch. The target power distribution relationship is one or more of the power distribution ratio, power-on duration ratio or duty cycle corresponding to each heating branch. The branch driving mode includes the connection relationship and power-on sequence of each heating branch. S4. When the target combined heating mode is inconsistent with the current combined heating mode established and being executed in the previous control cycle, first control the input power of the heating branch currently in the power-on state to be reduced to the preset transition power, and then control the switching drive component to change the connection relationship and power-on sequence of the central heating branch, the ring main heating branch and the edge compensation heating branch, so as to establish a target combined heating mode corresponding to the current cooking conditions. S5. During the cooking process, continuously collect temperature parameters of the center area of ​​the pot bottom, the edge area of ​​the pot bottom, and the steam detection parameters inside the pot. Based on the real-time collection results, re-determine the current cooking condition and adjust the currently executing joint heating mode. When the current cooking condition is determined to be a dry-burning risk condition, control the edge compensation heating branch to run according to the preset verification power for the preset verification time. Then, verify the dry-burning risk condition based on the temperature parameters of the center area of ​​the pot bottom, the temperature parameters of the edge area of ​​the pot bottom, and the state of steam in the pot. If the verification result shows that the pot is in a state of dry burning due to lack of liquid, control each heating branch to stop supplying power.

[0015] Furthermore, when the current cooking condition is continuous boiling, the main ring heating branch is continuously powered, and the central heating branch is intermittently powered; when the current cooking condition is simmering, the central heating branch and the main ring heating branch are connected in series and powered, and the edge compensation heating branch is intermittently powered according to the temperature difference between the center area of ​​the pot bottom and the edge area of ​​the pot bottom.

[0016] Compared with existing technologies, the electric hot pot multi-condition combined heating mode switching system that adopts the above technical solution has the following beneficial effects: Compared with existing technologies, this invention first sets up a central heating branch, a ring-shaped main heating branch, and an edge compensation heating branch, and combines them with the heat demand of different areas of the pot bottom for joint heating control. This means that the central area, main heating area, and edge area of ​​the pot bottom no longer use a fixed single heating method. As a result, a heat field distribution that is more in line with actual needs can be formed for different cooking stages. This improves the matching degree between the heat output of each area of ​​the pot bottom and the current cooking conditions, and improves the problems of existing electric hot pots that are prone to excessively rapid central heating, insufficient edge heating, or uneven overall heat field distribution during the heating process.

[0017] This invention collects temperature parameters from the center and edge areas of the pot bottom, as well as steam detection parameters inside the pot. The control component then combines these parameters with temperature rise changes, regional temperature differences, steam appearance status, and steam duration to comprehensively determine the current cooking condition. This eliminates reliance on a single temperature signal or time logic for determining the cooking state, enabling more accurate differentiation between rapid preheating, continuous boiling, steaming, simmering, heat preservation, and dry-burning risk conditions. This improves the accuracy of current condition identification and the reliability of control data.

[0018] This invention establishes a mapping relationship between cooking conditions and combined heating modes in advance. When a change in conditions is detected, the power of the currently energized branch is reduced to a preset transition power. Then, the switching drive component adjusts the connection relationship and energizing sequence of each heating branch. This makes the switching process of the combined heating mode have clear transition control and a phased execution process, thereby reducing current and thermal shocks during mode switching. It also improves the problems of control fluctuations, sudden heat changes and unstable cooking states that are easy to occur in the existing solutions during the conversion of different heating modes, and improves the stability of the multi-condition switching process.

[0019] This invention utilizes the temperature difference between the center and edge areas of the pot bottom during simmering, heat preservation, and other low-intensity heating stages to call up edge compensation heating branches as needed. This allows the edge area of ​​the pot bottom to receive targeted heat compensation even under overall power reduction operation conditions, thereby mitigating the temperature imbalance caused by rapid heat dissipation at the outer edge of the pot bottom, improving the thermal field balance and continuous cooking stability during low-power operation, and helping to reduce unnecessary continuous high-power output while meeting cooking needs.

[0020] This invention, when a risk of dry burning is initially determined, does not directly cut off the power based on a single abnormal signal. Instead, it first controls the edge compensation heating branch to run at a preset verification power for a preset verification time. Then, it combines the temperature changes in the center area of ​​the pot bottom, the temperature changes in the edge area of ​​the pot bottom, and whether the steam in the pot reappears during the verification period to verify the dry burning status. This changes the dry burning judgment process from a single judgment to a post-verification judgment, thereby reducing the probability of misjudgment caused by short-term fluctuations, local temperature rises, or transient changes in steam, improving the accuracy of dry burning identification and the reliability of protection control, and taking into account both safety of use and the continuity of normal cooking. Attached Figure Description

[0021] Figure 1 This is a system overall block diagram for an example.

[0022] Figure 2 The diagram below shows the thermal field acquisition and parameter input for an example.

[0023] Figure 3 The control discrimination and pattern generation block diagram is shown in the embodiment.

[0024] Figure 4 The following is a block diagram illustrating the switching drive and heating execution in an embodiment.

[0025] Figure 5 This is a flowchart illustrating the multi-condition combined heating mode switching process in an embodiment. Detailed Implementation

[0026] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0027] Example 1 like Figures 1-5 As shown, the electric hot pot multi-condition combined heating mode switching system includes a pot body, a zoned resistance heating component, a heat field acquisition component, a high-temperature connection base component, a switching drive component, and a control component.

[0028] The partitioned resistance heating assembly is located at the bottom of the pot body and includes a central heating branch, a ring-shaped main heating branch, and an edge compensation heating branch, respectively corresponding to the central area of ​​the pot bottom, the main heating area of ​​the pot bottom, and the edge compensation area of ​​the pot bottom.

[0029] The high-temperature connecting seat assembly is located outside the heating area at the bottom of the pot body. It includes a ceramic connecting base, multiple lead-out terminals mounted on the ceramic connecting base, and a heat-insulating partition between adjacent lead-out terminals. The central heating branch, the annular main heating branch, and the edge compensation heating branch are respectively connected to the corresponding lead-out terminals via high-temperature resistant transition conductive components.

[0030] The switching drive component is located in the non-heated area outside the high-temperature connector assembly and is electrically connected to each lead-out terminal. Under the control of the control component, the switching drive component changes the connection relationship and energizing sequence of the central heating branch, the ring main heating branch and the edge compensation heating branch.

[0031] The thermal field acquisition component is connected to the pot body and outputs temperature parameters of the central area of ​​the pot bottom, temperature parameters of the edge area of ​​the pot bottom, and steam detection parameters inside the pot.

[0032] The control component is electrically connected to the thermal field acquisition component and the switching drive component, respectively, and is used to receive temperature parameters of the center area of ​​the pot bottom, temperature parameters of the edge area of ​​the pot bottom, and steam detection parameters inside the pot, determine the current cooking condition, and output the target joint heating mode corresponding to the current cooking condition. The target joint heating mode includes the target power distribution relationship and branch drive mode corresponding to the center heating branch, the ring main heating branch, and the edge compensation heating branch. The target power distribution relationship is one or more of the power distribution ratio, power-on duration ratio, or duty cycle corresponding to each heating branch. The branch drive mode includes the connection relationship and power-on sequence of each heating branch.

[0033] When the target combined heating mode is inconsistent with the currently executed combined heating mode, the control component first controls the input power of the currently energized heating branch to be reduced to a preset transition power, and then controls the switching drive component to change the connection relationship and energization sequence of each heating branch in order to establish the target combined heating mode.

[0034] When the control component determines that the current cooking condition is a dry-burning risk condition, it first controls the edge compensation heating branch to run at a preset verification power for a preset verification time. Then, it verifies the dry-burning risk condition based on the temperature parameters of the center area of ​​the bottom of the pot, the temperature parameters of the edge area of ​​the bottom of the pot, and the state of steam in the pot. When the verification result shows that the pot is in a dry-burning state with insufficient liquid, it controls each heating branch to stop supplying power.

[0035] In this embodiment, the pot body is an electric pot body with a bottom heating surface, and a zoned resistance heating assembly is installed below the bottom heating surface. The central heating branch is arranged corresponding to the central area of ​​the pot bottom to form a concentrated heat source for the central area of ​​the pot bottom; the annular main heating branch is arranged around the central heating branch to form a continuous main heating zone for the main body heating area of ​​the pot bottom; and the edge compensation heating branch is arranged near the outer edge of the pot bottom to form a supplementary heating zone for the edge compensation area of ​​the pot bottom. By dividing the pot bottom heating area into three functional areas—central, main, and edge compensation—the pot bottom heat field is no longer determined by a single heating area, but can be zoned and adjusted according to the heating state of different areas of the pot bottom.

[0036] In this embodiment, the high-temperature connecting seat assembly is located outside the high-temperature heating area at the bottom of the pot body, and is used to reliably lead each heating branch from the high-temperature area to the non-heating area, thereby enabling the switching drive assembly to complete series, parallel, or alternating drive switching in a lower temperature environment. The control component can be implemented using a microcontroller control unit, an embedded controller, or other control unit with sampling processing, logic discrimination, and output control capabilities, and stores operating condition discrimination rules and mode mapping rules internally.

[0037] Furthermore, the switching drive assembly includes a branch selection switch unit and a timing drive unit. The branch selection switch unit is electrically connected to each lead-out terminal and is used to establish a series or parallel path between the central heating branch, the ring-shaped main heating branch, and the edge compensation heating branch under the control of the control assembly. The timing drive unit is used to control each heating branch to be continuously, intermittently, or alternately turned on according to the conduction cycle output by the control assembly. Therefore, the switching drive assembly does not only perform simple on / off control, but also simultaneously undertakes the reconstruction of branch connection relationships and the reconstruction of branch energization timing.

[0038] Furthermore, the target power allocation relationship can be characterized by both the branch target power and the branch duty cycle. Let the first... The total target heating power within each control cycle is the total target heating power within each control cycle. The central heating branch, the ring-shaped main heating branch, and the edge compensation heating branch are in the first The target branch power corresponding to each control cycle is as follows: , and Then we have:

[0039] Furthermore, a central heating branch, a ring-shaped main heating branch, and an edge compensation heating branch are set in the... The target power allocation ratios within each control cycle are respectively , and Then we have:

[0040]

[0041]

[0042] in, Indicates the first Total target heating power within each control cycle Indicates the target branch power of the central heating branch. This indicates the target branch power of the ring-shaped main heating branch. This indicates the target branch power of the edge-compensated heating branch. , and These represent the target power distribution ratios for the three heating branches.

[0043] When a heating branch uses intermittent or alternating pulse energizing, its equivalent heating effect within a single control cycle is also related to the duty cycle. Let the first... The heating branch is in the first The conduction time within each control cycle is The duration of a single control cycle is Then the duty cycle of that branch is for:

[0044] in, These correspond to the central heating branch, the ring-shaped main heating branch, and the edge compensation heating branch, respectively. Therefore, the target combined heating mode can be determined by the connection relationship of each heating branch, the target power distribution ratio, and the duty cycle.

[0045] Furthermore, the central heating branch, the annular main heating branch, and the edge compensation heating branch are each composed of one or more resistive heating sections; the branch driving modes include parallel high-power driving mode, series steady-state driving mode, edge compensation driving mode, and alternating pulse driving mode.

[0046] Among them, the parallel high-power drive mode is to energize at least two heating branches in parallel; the series steady-state drive mode is to energize the central heating branch and the ring main heating branch in series; the edge compensation drive mode is to energize the edge compensation heating branch and the central heating branch or the ring main heating branch together; and the alternating pulse drive mode is to alternately conduct at least two heating branches according to a preset timing sequence.

[0047] In this embodiment, the branch selection switch unit can be composed of a relay group, a solid-state relay group, or a semiconductor power switch device, and is used to change the electrical connection relationship between the central heating branch, the ring main heating branch, and the edge compensation heating branch under the control of the control component, so as to realize the independent conduction, series drive, parallel drive, or alternating conduction of each heating branch; the timing drive unit can be composed of a PWM drive circuit, a controllable on / off drive circuit, or a timing drive control module, and is used to control the conduction sequence, conduction duration, duty cycle, and switching cycle of each heating branch.

[0048] After determining the target combined heating mode, the control component first outputs a connection switching control signal to the branch selection switch unit, and then outputs a power-on timing control signal to the timing drive unit, so that each heating branch enters the target operating state according to the corresponding connection relationship and power-on cycle. During the mode switching process, the branch selection switch unit and the timing drive unit cooperate with each other so that each heating branch enters the corresponding power-on control stage after completing the connection relationship switch, thereby improving the execution stability and control reliability of the combined heating mode switching process.

[0049] In this embodiment, the parallel high-power drive mode is used in the rapid preheating stage or the initial heating stage of the liquid to establish the overall thermal field of the pot bottom in a short time; the series steady-state drive mode is used in the simmering stage or the smooth transition stage from high heat to low heat to reduce the overall input power and reduce the local temperature rise fluctuation of the pot bottom; the edge compensation drive mode is used in the edge correction process when the heat dissipation of the edge area of ​​the pot bottom is faster and the temperature difference between the center and the edge increases; the alternating pulse drive mode is used in the heat preservation stage or the steady-state adjustment stage after continuous boiling to reduce the peak load and allow different areas of the pot bottom to receive heat input in turn.

[0050] Furthermore, the thermal field acquisition component includes a center temperature sensor, an edge temperature sensor, and a steam state sensor. The center temperature sensor is preferably located at the center of the outer side of the pot bottom; the edge temperature sensor is preferably located on the outer side of the pot bottom, near the outer edge and avoiding the high-temperature connecting seat assembly's lead-out area; and the steam state sensor is preferably located at the steam escape passage of the pot lid, or near the steam accumulation passage at the upper opening of the pot body. The center temperature sensor and the edge temperature sensor can be thermistors, thermocouples, or other temperature sensors suitable for pot bottom temperature acquisition; the steam state sensor can be a humidity sensor, a temperature and humidity integrated sensor, or a steam condensation detection sensor.

[0051] The center temperature sensor outputs the temperature parameters of the center area of ​​the bottom of the pot, the edge temperature sensor outputs the temperature parameters of the edge area of ​​the bottom of the pot, and the steam state sensor outputs the steam detection parameters inside the pot.

[0052] The control component determines the steam appearance status parameters and the steam duration parameters based on the steam detection parameters inside the boiler.

[0053] Furthermore, the control component determines the current cooking condition based on the temperature rise rate of the central region of the pot bottom, the temperature rise rate of the edge region of the pot bottom, the temperature difference between the central region and the edge region of the pot bottom, and the state of steam appearance inside the pot; the state of steam appearance inside the pot includes no steam, initial steam appearance, and continuous steam appearance; the current cooking condition includes rapid preheating, continuous boiling, steaming, simmering, heat preservation, and dry-burning risk conditions.

[0054] In this embodiment, the control component does not directly determine the working condition based on a single instantaneous sampling value, but calculates the temperature rise rate of the central region of the pot bottom, the temperature rise rate of the edge region of the pot bottom, and the temperature difference between the central region of the pot bottom and the edge region of the pot bottom within a sliding time window.

[0055] Let the first The temperature parameters of the central region of the pot bottom collected at each sampling time are as follows: , No. The temperature parameters of the pot bottom edge region collected at each sampling time are: , No. The time corresponding to each sampling moment is The number of sampling steps corresponding to the sliding time window is The rate of temperature rise in the central area of ​​the pot bottom Temperature rise rate of the edge area of ​​the pot bottom and the temperature difference between the center and the edge They are respectively:

[0056]

[0057]

[0058] in, Indicates the first The temperature rise rate of the central region of the pot bottom at each sampling time. Indicates the first The temperature rise rate of the pot bottom edge region at each sampling time. Indicates the first The temperature difference at the center edge corresponding to each sampling time.

[0059] Regarding steam state determination, let the first... The steam detection parameters inside the boiler at the time of the second sampling were: The threshold for determining the presence of steam is Then the steam state variables for:

[0060] Let the time interval between two adjacent samples be . Then the first Steam duration parameter corresponding to each sampling time for:

[0061] in, Indicates the first Steam state variables at the time of the second sampling Indicates the first The steam duration parameter corresponds to each sampling time. The control component is based on... The values ​​and The size of the steam in the pot is used to classify the steam appearance state into three categories: no steam, initial steam appearance, and continuous steam appearance.

[0062] Based on the temperature rise rate of the center area of ​​the pot bottom, the temperature rise rate of the edge area of ​​the pot bottom, the temperature difference between the center and the edge, and the state of steam in the pot, the control component determines the current cooking condition. Specifically, when there is no steam in the pot, and the temperature rise rates of both the center and edge areas of the pot bottom are higher than the preset preheating rate threshold, it is determined to be a rapid preheating condition; when there is continuous steam in the pot, and the temperature rise rates of both the center and edge areas of the pot bottom drop to a stable range, it is determined to be a continuous boiling condition; when steam is continuously present in the pot, and the temperature change of the pot bottom tends to be gradual, and the temperature difference between the center and the edge is within the steam environment maintenance range, it is determined to be a steaming condition; when there is no steam in the pot... When the steam condition is either initially present or continuously present, and the temperature rise rate in both the center and edge areas of the pot bottom is lower than the threshold value corresponding to continuous boiling, it is determined to be a simmering condition. When both the temperature parameters in the center and edge areas of the pot bottom are close to the target temperature for heat preservation, and the temperature difference between the center and edge is within the allowable range, it is determined to be a heat preservation condition. When the steam condition inside the pot remains unchanged (no steam), and both the temperature parameters in the center and edge areas of the pot bottom continue to rise, it is preliminarily determined to be a dry-burning risk condition. The above-mentioned threshold values ​​can be determined by the factory calibration results under the corresponding pot body structure, heating branch layout, and sensor arrangement conditions.

[0063] Furthermore, the control component pre-stores the correspondence between operating conditions and target combined heating modes. For rapid preheating, the control component establishes a parallel high-power drive mode for the central heating branch and the ring-shaped main heating branch to quickly establish an overall thermal field in the central region and the main heating area of ​​the pot bottom. When a significant lag in heating is detected in the edge region of the pot bottom, the edge compensation heating branch is synchronously or intermittently activated. For continuous boiling, the control component continuously powers the ring-shaped main heating branch and intermittently powers the central heating branch to maintain continuous boiling of the liquid in the pot and suppress heat overshoot in the central region. When accelerated heat dissipation in the edge region of the pot bottom leads to an increase in the temperature difference between the center and edge, the edge compensation heating branch is briefly activated.

[0064] For steaming conditions, the control unit controls the main ring heating branch to operate continuously as the main heating branch, and controls the edge compensation heating branch to be intermittently turned on according to the temperature difference between the center area and the edge area of ​​the pot bottom, while reducing the duty cycle of the central heating branch to maintain a stable steam environment.

[0065] For stewing, the control component establishes a series steady-state drive mode for the central heating branch and the ring main heating branch, and controls the intermittent conduction of the edge compensation heating branch according to the temperature difference between the central area and the edge area of ​​the pot bottom.

[0066] For heat preservation conditions, the control component controls the central heating branch or the ring main heating branch to alternately pulse conduction according to a preset low duty cycle, and briefly calls the edge compensation heating branch to correct when the temperature difference between the center area of ​​the pot bottom and the edge area of ​​the pot bottom exceeds the allowable range.

[0067] For dry-burning risk conditions, the control component does not directly maintain the original combined heating mode, but limits the input power of the currently energized branch and calls the edge compensation heating branch to run at the preset verification power for the preset verification time in order to complete the dry-burning verification due to lack of liquid.

[0068] Furthermore, the preset transition power is lower than the input power of the corresponding heating branch before switching.

[0069] In this embodiment, when the control component determines that the target combined heating mode is inconsistent with the currently executed combined heating mode, it does not directly change the connection relationship between the heating branches. Instead, it first controls the input power of the currently energized heating branch to decrease to a preset transition power, and then controls the switching drive component to change the connection relationship and energizing sequence of each heating branch. The preset transition power can be achieved by reducing the duty cycle, shortening the on-time, or extending the off-time. By adopting the method of first reducing the load and then switching, the instantaneous current and thermal shocks caused by directly switching branches under full load can be reduced, and the stability of the branch connection relationship reconstruction process can be improved.

[0070] Furthermore, the ceramic connecting base is provided with heat-insulating partitions distributed along each lead-out terminal; the high-temperature resistant transition conductive element is one of a high-temperature resistant metal sheet, a high-temperature resistant braided conductor, or a high-temperature resistant elastic conductor.

[0071] In this embodiment, the ceramic connecting base is fixed to the outside of the high-temperature heating area at the bottom of the pot, and its installation position avoids areas where the heat flux density at the bottom of the pot is concentrated. Multiple lead-out terminals correspond to the lead-out ends of the central heating branch, the annular main heating branch, and the edge compensation heating branch, respectively. The heat insulation partition can be configured as a ceramic insulating rib extending along the arrangement direction of the lead-out terminals or other insulating isolation structures, used to extend the creepage path between adjacent lead-out terminals and reduce thermal coupling. The high-temperature resistant transition conductive element extends from the high-temperature area at the bottom of the pot to the lead-out terminals, allowing for slight displacement due to thermal expansion of the pot body while ensuring conductivity, thereby reducing the risk of fatigue damage caused by rigid connections.

[0072] Furthermore, it also includes a branch electrical parameter acquisition unit; the branch electrical parameter acquisition unit is used to acquire the current parameters and voltage parameters of each heating branch, or to acquire the resistance parameters determined by the current parameters and voltage parameters of each heating branch; the control component determines the conduction state, normal load state, open circuit state, short circuit state or resistance drift state of each heating branch based on the electrical parameters of each heating branch.

[0073] In this embodiment, the branch electrical parameter acquisition unit is connected to the detection circuits of the central heating branch, the ring main heating branch, and the edge compensation heating branch, respectively, and is used to acquire the current and voltage parameters of each heating branch. Let the first... The heating branch is in the first The branch voltage parameters within each control cycle are: The branch current parameters are Then the resistance parameters of this branch for:

[0074] in, Indicates the first Resistance parameters of the heating branch Indicates the first Voltage parameters at both ends of the heating branch, Indicates the first The current parameters of each heating branch. The control component preferably operates when the corresponding branch is in the on state and... Calculate when the current exceeds the preset minimum effective current threshold. This is to avoid calculation errors under low current conditions.

[0075] Based on current, voltage, and resistance parameters, the control component determines the conduction, normal load, open circuit, short circuit, or resistance drift status of each heating branch. Specifically, when the corresponding branch has received a conduction command and both current and voltage parameters are within the calibrated operating range, it is determined to be in a normal load state; when the corresponding branch has received a conduction command but the current parameter remains below the minimum effective current threshold, it is determined to be in an open circuit state; when the current parameter abnormally increases and the resistance parameter is below the short circuit threshold, it is determined to be in a short circuit state; when the resistance parameter deviates from the factory-calibrated resistance value beyond the allowable drift range, it is determined to be in a resistance drift state. After identifying an abnormal branch, the control component prohibits the current combined heating mode from continuing to use the corresponding abnormal branch and switches to protection mode or derating operation mode.

[0076] In this embodiment, when the control component detects that a certain heating branch is in an open circuit state, a short circuit state, or a resistance drift state, it does not continue to drive all heating branches according to the original target joint heating mode, but instead executes the corresponding abnormal handling strategy according to the type of abnormal branch and the area where it is located.

[0077] Specifically, when the central heating branch is abnormal, the control component prohibits the subsequent joint heating mode from calling the central heating branch, and controls the ring main heating branch to operate as the main heating branch. The edge compensation heating branch is connected to compensate for the temperature difference between the central area of ​​the pot bottom and the edge area of ​​the pot bottom in order to maintain the main heat field of the pot bottom. When the main ring heating branch malfunctions, the control component restricts the whole machine from entering the high-power combined heating state, and controls the central heating branch to undertake the basic heating function, while the edge compensation heating branch is intermittently turned on as needed to avoid continuous heat loss in the main body area of ​​the pot bottom. When the edge compensation heating branch is abnormal, the control component prohibits the use of edge correction control and verification dry burning verification process that rely on the edge compensation heating branch, and increases the sensitivity of protection judgment corresponding to the temperature difference between the center area of ​​the pot bottom and the edge area of ​​the pot bottom. When the steam status sensor malfunctions or the steam detection parameters are inaccurate, the control unit switches to a temperature protection mode based solely on the temperature parameters of the center and edge areas of the pot bottom. This allows the system to maintain basic heating functionality even in the event of a localized circuit malfunction or sensor failure, and reduces the risk of the abnormal condition escalating further.

[0078] Furthermore, when the control component verifies the dry-burning risk condition, it determines whether the pot is in a state of liquid shortage and dry burning based on the changes in the temperature parameters of the center area of ​​the pot bottom, the temperature parameters of the edge area of ​​the pot bottom, and the state of steam appearance in the pot during the operation of the edge compensation heating branch at the preset verification power. Within the preset verification time, if the state of steam appearance in the pot remains without steam, and the temperature parameters of the center area of ​​the pot bottom and the temperature parameters of the edge area of ​​the pot bottom continue to rise relative to the start time of verification, it is determined that the pot is in a state of liquid shortage and dry burning.

[0079] In this embodiment, the control component does not immediately cut off all heating branches after initially identifying a dry-burning risk condition. Instead, it performs a verification check through the edge compensation heating branch. Specifically, when the control component initially determines that the current cooking condition is a dry-burning risk condition, it first controls the edge compensation heating branch to run at a preset verification power for a preset verification time. Then, it determines whether the pot is in a dry-burning state due to a lack of liquid based on the temperature parameters of the center area of ​​the pot bottom, the temperature parameters of the edge area of ​​the pot bottom, and the state of steam in the pot. The edge compensation heating branch is selected for verification because the edge compensation heating branch corresponds to the compensation area of ​​the pot bottom, where the thermal disturbance is relatively small. This makes it easier to observe whether the steam recovers and whether the pot bottom temperature continues to rise abnormally without significantly increasing the central heat load.

[0080] Let the sampling sequence number corresponding to the start time of the verification be . The sampling sequence number corresponding to the end of the verification is The temperature increase in the central area of ​​the pot bottom during the verification period is... Temperature increase in the area around the bottom edge of the pot They are respectively:

[0081]

[0082] Let the verification period be the first The steam state variable corresponding to the next sample is The time interval between two adjacent samples is The cumulative occurrence time of steam during the verification period. for:

[0083] in, This indicates the temperature increase in the central area of ​​the pot bottom during the verification period. This indicates the temperature increase in the pot bottom edge area during the verification period. This indicates the cumulative time of steam occurrence during the verification period. After the verification is completed, when... Less than the preset steam recovery threshold, and Greater than the center temperature rise verification threshold When the temperature rise exceeds the edge temperature verification threshold, the control component determines that the pot is in a state of dry burning due to lack of liquid and stops supplying power to each heating branch. If steam reappears during the verification period, or if at least one of the temperature rise in the center area of ​​the pot bottom or the temperature rise in the edge area of ​​the pot bottom fails to reach the corresponding verification threshold, the dry burning due to lack of liquid is cancelled, and the current cooking condition is re-evaluated based on the verified temperature parameters and the steam appearance status. Through the above verification process, the final determination of the dry burning risk condition is based on the joint judgment of the temperature parameters in the center area of ​​the pot bottom, the temperature parameters in the edge area of ​​the pot bottom, and the steam appearance status inside the pot.

[0084] In this embodiment, the preset transition power, preset verification power, preset verification duration, minimum effective current threshold, short circuit judgment threshold, allowable drift range, and allowable temperature difference range between the center area and the edge area of ​​the pot bottom can all be calibrated and determined based on the product's rated power, pot volume, resistance design of each heating branch, sensor installation position, and factory test results under standard load conditions.

[0085] Specifically, temperature parameters of the center area of ​​the pot bottom, temperature parameters of the edge area of ​​the pot bottom, steam detection parameters, and current and voltage parameters of each heating branch can be collected under empty pot conditions, standard water load conditions, and typical cooking load conditions. In combination with the changes in heat field distribution, steam occurrence sequence, and branch load characteristics under different working conditions, calibration intervals for the corresponding parameters can be established.

[0086] During actual operation, the control component calls the corresponding parameters within the calibration range to perform working condition judgment, mode switching, anomaly identification, and dry burning verification, thereby giving each preset parameter a clear basis for determination and improving the adaptability of the control logic under different pot specifications and different cooking load conditions.

[0087] In this embodiment, the zoned resistance heating assembly is located at the bottom of the pot body and is divided into a central heating branch, a ring-shaped main heating branch, and an edge compensation heating branch according to different heat demand areas on the pot bottom. The central heating branch is used for concentrated heating of the central area of ​​the pot bottom, the ring-shaped main heating branch is used for continuous heating of the main heating area of ​​the pot bottom, and the edge compensation heating branch is used to supplement and correct the heat loss of areas at the edges of the pot bottom. Each heating branch is led out to a high-temperature connector assembly via a high-temperature resistant transition conductive component. A switching drive assembly located in the low-temperature region then switches the connection relationship and controls the power-on sequence of each heating branch, thus enabling the heat output of the pot bottom to be adjusted in a combined manner according to the actual thermal state during cooking, rather than using a fixed single method.

[0088] During cooking, the heat field acquisition component continuously collects temperature parameters from the center and edge areas of the pot bottom, as well as steam detection parameters, and transmits the results to the control component. The control component combines the temperature rise changes in the center and edge areas of the pot bottom, the temperature difference between the two areas, the steam appearance status, and the duration of steam appearance to comprehensively determine the current cooking state, distinguishing between rapid preheating, continuous boiling, steaming, simmering, heat preservation, and dry-burning risk conditions.

[0089] After determining the current cooking conditions, the control component generates a target combined heating mode that matches the current cooking conditions based on the preset mapping relationship between the conditions and the heating modes. The target combined heating mode includes the power distribution relationship, connection relationship and power-on sequence of each heating branch.

[0090] When the control component determines that the current cooking conditions have changed and the target combined heating mode is inconsistent with the current execution mode, it first controls the heating branch that is currently energized to reduce to a preset transition power, and then controls the switching drive component to adjust the connection relationship and energizing sequence between the central heating branch, the ring main heating branch and the edge compensation heating branch in order to establish a new target combined heating mode.

[0091] In rapid preheating mode, the central heating branch and the ring main heating branch can work together to improve the overall heating speed of the pot bottom. In continuous boiling mode, the ring main heating branch can maintain continuous heating of the main area, while the central heating branch provides supplementary heating. In simmering mode, the overall heating intensity can be reduced, and the edge compensation heating branch can be controlled to be turned on as needed based on the temperature difference between the central area and the edge area of ​​the pot bottom to maintain a balanced thermal field at the bottom of the pot. In heat preservation mode, the temperature inside the pot is maintained by a low duty cycle, and the edge compensation heating branch is called to correct the temperature drop in the edge area when a rapid drop is detected. This allows the heat output of different areas of the pot bottom to be dynamically matched with changes in cooking conditions.

[0092] During the aforementioned dynamic switching process, the control component continuously receives feedback data from the thermal field acquisition component, cyclically reassesses the current cooking conditions, and makes real-time corrections to the current combined heating mode. When the control component initially determines that there is a risk of dry burning based on the temperature parameters of the center area of ​​the pot bottom, the temperature parameters of the edge area of ​​the pot bottom, and the steam status inside the pot, it first controls the edge compensation heating branch to run at the preset verification power for the preset verification time. Then, it combines the temperature changes of the center area of ​​the pot bottom, the temperature changes of the edge area of ​​the pot bottom, and whether the steam inside the pot has recovered during the verification period to verify the dry burning state due to liquid shortage.

[0093] If the steam inside the pot fails to recover during the verification period, and the temperature in both the center and edge areas of the pot bottom continues to rise, the pot is determined to be in a dry-burning state due to a lack of liquid, and power to all heating circuits is stopped. If steam reappears during the verification period, or the temperature rise at the bottom of the pot does not reach the corresponding abnormal conditions, the dry-burning determination is cancelled, and the current cooking condition and corresponding combined heating mode are re-determined based on the verified thermal field parameters and steam status. This achieves accurate identification, smooth switching, and dynamic correction of the combined heating mode under different cooking conditions of the electric hot pot.

[0094] Example 2 like Figure 5 As shown, this embodiment of the invention provides a method for switching multiple heating modes of an electric hot pot based on the aforementioned multi-condition combined heating mode switching system, comprising the following steps: S1. Collect temperature parameters of the center area of ​​the bottom of the pot, temperature parameters of the edge area of ​​the bottom of the pot, and steam detection parameters inside the pot.

[0095] S2. Determine the state of steam in the pot based on the steam detection parameters, and determine the current cooking conditions based on the temperature parameters of the center area of ​​the bottom of the pot, the temperature parameters of the edge area of ​​the bottom of the pot, and the state of steam in the pot.

[0096] S3. Generate a corresponding target combined heating mode based on the current cooking conditions. The target combined heating mode includes the target power distribution relationship and branch driving mode corresponding to the central heating branch, the ring main heating branch and the edge compensation heating branch. The target power distribution relationship is one or more of the power distribution ratio, power-on duration ratio or duty cycle corresponding to each heating branch. The branch driving mode includes the connection relationship and power-on sequence of each heating branch.

[0097] S4. When the target combined heating mode is inconsistent with the current combined heating mode established and being executed in the previous control cycle, first control the input power of the heating branch currently in the power-on state to be reduced to the preset transition power, and then control the switching drive component to change the connection relationship and power-on sequence of the central heating branch, the ring main heating branch and the edge compensation heating branch, so as to establish a target combined heating mode corresponding to the current cooking conditions.

[0098] S5. During the cooking process, continuously collect temperature parameters of the center area of ​​the pot bottom, the edge area of ​​the pot bottom, and the steam detection parameters inside the pot. Based on the real-time collection results, re-determine the current cooking condition and adjust the currently executing joint heating mode. When the current cooking condition is determined to be a dry-burning risk condition, control the edge compensation heating branch to run according to the preset verification power for the preset verification time. Then, verify the dry-burning risk condition based on the temperature parameters of the center area of ​​the pot bottom, the temperature parameters of the edge area of ​​the pot bottom, and the state of steam in the pot. If the verification result shows that the pot is in a state of dry burning due to lack of liquid, control each heating branch to stop supplying power.

[0099] In this embodiment, S1 to S5 are executed by the control component in Embodiment 1 in conjunction with the thermal field acquisition component, the switching drive component, and the partitioned resistance heating component.

[0100] In S1, the control component reads the output values ​​of the center temperature sensor, the edge temperature sensor, and the steam state sensor in each control cycle, and writes the collected results into the buffer for subsequent operation condition judgment and mode switching.

[0101] In S2, the control component is based on the steam state variables. and steam duration parameter Determine the state of steam formation inside the pot, and combine this with the rate of temperature rise in the central area of ​​the pot bottom. Temperature rise rate of the edge area of ​​the pot bottom and the temperature difference between the center and the edge Determine the current cooking conditions.

[0102] In S3, the control component determines the corresponding target power allocation ratio, branch connection relationship and branch power-on sequence according to the current cooking condition calling mode mapping rules, and combines them to form a target joint heating mode.

[0103] In S4, the control component compares the target combined heating mode with the current combined heating mode established and being executed in the previous control cycle. When the two are inconsistent, the load reduction process is executed first, and then the switching drive component is driven to change the connection relationship and power-on sequence of each heating branch.

[0104] In S5, the control component continuously collects parameters, re-evaluates operating conditions, and updates modes throughout the cooking process. When the current cooking condition is determined to be a dry-burning risk condition, it enters the verification and review process. Based on the changes in temperature parameters of the center area of ​​the pot bottom, temperature parameters of the edge area of ​​the pot bottom, and the state of steam in the pot during the verification period, a final judgment of dry-burning due to lack of liquid is made.

[0105] Furthermore, when the current cooking condition is continuous boiling, the main ring heating branch is continuously powered, and the central heating branch is intermittently powered; when the current cooking condition is simmering, the central heating branch and the main ring heating branch are connected in series and powered, and the edge compensation heating branch is intermittently powered according to the temperature difference between the center area of ​​the pot bottom and the edge area of ​​the pot bottom.

[0106] In this embodiment, when the current cooking condition is continuous boiling, the annular main heating branch, as the continuous heating branch for the main heating area of ​​the pot bottom, remains continuously energized to ensure that the liquid in the pot maintains a continuous boiling state. The central heating branch compensates for the heat in the central area of ​​the pot bottom by intermittently energizing to suppress local overshoot caused by prolonged high heat in the central area of ​​the pot bottom. The intermittent energizing means that the central heating branch alternately executes the on and off states according to a preset conduction rhythm within multiple consecutive control cycles. The conduction rhythm is dynamically adjusted based on the temperature parameters of the central area of ​​the pot bottom, the temperature parameters of the edge area of ​​the pot bottom, and the state of steam in the pot.

[0107] When the current cooking mode is simmering or stewing, the control component connects the central heating branch and the main ring heating branch in series, thereby reducing the overall input power compared to the parallel high-power drive mode. This allows the pot to smoothly transition from continuous boiling to a low-heat maintenance state. If the heat dissipation at the edge of the pot is faster, causing an increase in the temperature difference between the center and the edge, the control component intermittently activates the edge compensation heating branch to provide supplemental heating to the edge area as needed. Once the temperature difference at the center and edge returns to the target range, the edge compensation heating branch deactivates. Therefore, in simmering or stewing mode, the power is not uniformly reduced across the entire pot, but rather, while reducing the overall power, the independent correction capability for the edge area of ​​the pot is maintained.

[0108] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A multi-condition combined heating mode switching system for electric hot pot, characterized in that, It includes the pot body, zoned resistance heating components, thermal field acquisition components, high-temperature connection base components, switching drive components, and control components; The partitioned resistance heating assembly is located at the bottom of the pot body and includes a central heating branch, a ring-shaped main heating branch, and an edge compensation heating branch, respectively corresponding to the central area of ​​the pot bottom, the main heating area of ​​the pot bottom, and the edge compensation area of ​​the pot bottom. The high-temperature connecting seat assembly is located outside the heating area at the bottom of the pot body. It includes a ceramic connecting base, multiple lead-out terminals mounted on the ceramic connecting base, and a heat-insulating partition between adjacent lead-out terminals. The central heating branch, the annular main heating branch, and the edge compensation heating branch are respectively connected to the corresponding lead-out terminals via high-temperature resistant transition conductive parts. The switching drive component is located in the non-heated area outside the high-temperature connector assembly and is electrically connected to each lead-out terminal. Under the control of the control component, the switching drive component changes the connection relationship and energizing sequence of the central heating branch, the ring main heating branch and the edge compensation heating branch. The thermal field acquisition component is connected to the pot body and outputs temperature parameters of the central area of ​​the pot bottom, temperature parameters of the edge area of ​​the pot bottom, and steam detection parameters inside the pot. The control component is electrically connected to the thermal field acquisition component and the switching drive component, respectively, and is used to receive temperature parameters of the center area of ​​the pot bottom, temperature parameters of the edge area of ​​the pot bottom, and steam detection parameters inside the pot, determine the current cooking condition, and output the target joint heating mode corresponding to the current cooking condition. The target joint heating mode includes the target power distribution relationship and branch drive mode corresponding to the center heating branch, the ring main heating branch, and the edge compensation heating branch. The target power distribution relationship is one or more of the power distribution ratio, power-on duration ratio, or duty cycle corresponding to each heating branch. The branch drive mode includes the connection relationship and power-on sequence of each heating branch. When the target combined heating mode is inconsistent with the currently executed combined heating mode, the control component first controls the input power of the heating branch that is currently energized to be reduced to a preset transition power, and then controls the switching drive component to change the connection relationship and energization sequence of each heating branch in order to establish the target combined heating mode. When the control component determines that the current cooking condition is a dry-burning risk condition, it first controls the edge compensation heating branch to run at a preset verification power for a preset verification time. Then, it verifies the dry-burning risk condition based on the temperature parameters of the center area of ​​the bottom of the pot, the temperature parameters of the edge area of ​​the bottom of the pot, and the state of steam in the pot. When the verification result shows that the pot is in a dry-burning state with insufficient liquid, it controls each heating branch to stop supplying power.

2. The electric hot pot multi-condition combined heating mode switching system according to claim 1, characterized in that: The central heating branch, the ring-shaped main heating branch, and the edge compensation heating branch are each composed of one or more resistive heating sections; the branch driving modes include parallel high-power driving mode, series steady-state driving mode, edge compensation driving mode, and alternating pulse driving mode; Its parallel high-power drive mode is that the two heating branches are energized in parallel; the series steady-state drive mode is that the central heating branch and the ring main heating branch are energized in series; the edge compensation drive mode is that the edge compensation heating branch and the central heating branch or the ring main heating branch are energized together; and the alternating pulse drive mode is that the two heating branches are alternately turned on according to a preset timing sequence.

3. The electric hot pot multi-condition combined heating mode switching system according to claim 1, characterized in that: The thermal field acquisition component includes a center temperature sensor, an edge temperature sensor, and a steam state sensor. The center temperature sensor outputs the temperature parameters of the center area of ​​the bottom of the pot, the edge temperature sensor outputs the temperature parameters of the edge area of ​​the bottom of the pot, and the steam state sensor outputs the steam detection parameters inside the pot. The control component determines the steam appearance status parameters and the steam duration parameters based on the steam detection parameters inside the boiler.

4. The multi-condition combined heating mode switching system for electric hot pot according to claim 1, characterized in that: The control component determines the current cooking condition based on the temperature rise rate of the central area of ​​the pot bottom, the temperature rise rate of the edge area of ​​the pot bottom, the temperature difference between the central area and the edge area of ​​the pot bottom, and the state of steam in the pot. The steam state inside the pot includes no steam state, initial steam state, and continuous steam state. The current cooking conditions include rapid preheating, continuous boiling, steaming, braising, heat preservation, and dry-burning risk conditions.

5. The multi-condition combined heating mode switching system for electric hot pot according to claim 1, characterized in that: The preset transition power is lower than the input power of the corresponding heating branch before switching.

6. The electric hot pot multi-condition combined heating mode switching system according to claim 1, characterized in that: The ceramic connecting base is provided with heat-insulating partitions distributed along each lead-out terminal; the high-temperature resistant transition conductive component is one of a high-temperature resistant metal sheet, a high-temperature resistant braided conductor, or a high-temperature resistant elastic conductor.

7. The electric hot pot multi-condition combined heating mode switching system according to claim 1, characterized in that: It also includes a branch electrical parameter acquisition unit; the branch electrical parameter acquisition unit is used to acquire the current parameters and voltage parameters of each heating branch, or to acquire the resistance parameters determined by the current parameters and voltage parameters of each heating branch; the control component determines the conduction state, normal load state, open circuit state, short circuit state or resistance drift state of each heating branch based on the electrical parameters of each heating branch.

8. The electric hot pot multi-condition combined heating mode switching system according to claim 4, characterized in that: When the control component verifies the dry-burning risk condition, it determines whether the pot is in a state of liquid shortage and dry burning based on the temperature parameters of the central area of ​​the pot bottom, the temperature parameters of the edge area of ​​the pot bottom, and the changes in the state of steam in the pot during the operation of the edge compensation heating branch at the preset verification power. Within the preset verification time, if the steam in the pot remains in a state of no steam and the temperature parameters of the central area and the edge area of ​​the pot bottom continue to rise relative to the start time of verification, it is determined that the pot is in a state of dry burning due to lack of liquid.

9. A method for switching between multiple operating conditions and combined heating modes in an electric hot pot, characterized in that, Includes the following steps: S1. Collect temperature parameters of the central area of ​​the bottom of the pot, temperature parameters of the edge area of ​​the bottom of the pot, and steam detection parameters inside the pot. S2. Determine the state of steam in the pot based on the steam detection parameters, and determine the current cooking conditions based on the temperature parameters of the center area of ​​the bottom of the pot, the temperature parameters of the edge area of ​​the bottom of the pot, and the state of steam in the pot. S3. Generate a corresponding target combined heating mode based on the current cooking conditions. The target combined heating mode includes the target power distribution relationship and branch driving mode corresponding to the central heating branch, the ring main heating branch and the edge compensation heating branch. The target power distribution relationship is one or more of the power distribution ratio, power-on duration ratio or duty cycle corresponding to each heating branch. The branch driving mode includes the connection relationship and power-on sequence of each heating branch. S4. When the target combined heating mode is inconsistent with the current combined heating mode established and being executed in the previous control cycle, first control the input power of the heating branch currently in the power-on state to be reduced to the preset transition power, and then control the switching drive component to change the connection relationship and power-on sequence of the central heating branch, the ring main heating branch and the edge compensation heating branch, so as to establish a target combined heating mode corresponding to the current cooking conditions. S5. During the cooking process, continuously collect temperature parameters of the center area of ​​the pot bottom, the edge area of ​​the pot bottom, and the steam detection parameters inside the pot. Based on the real-time collection results, re-determine the current cooking condition and adjust the currently executing joint heating mode. When the current cooking condition is determined to be a dry-burning risk condition, control the edge compensation heating branch to run according to the preset verification power for the preset verification time. Then, verify the dry-burning risk condition based on the temperature parameters of the center area of ​​the pot bottom, the temperature parameters of the edge area of ​​the pot bottom, and the state of steam in the pot. If the verification result shows that the pot is in a state of dry burning due to lack of liquid, control each heating branch to stop supplying power.

10. The method for switching between multiple operating conditions and combined heating modes of an electric hot pot according to claim 9, characterized in that: When the current cooking condition is continuous boiling, the main ring heating branch is continuously powered, and the central heating branch is intermittently powered. When the current cooking condition is simmering, the central heating branch and the main ring heating branch are connected in series and powered, and the edge compensation heating branch is intermittently powered according to the temperature difference between the center area and the edge area of ​​the pot bottom.

Images