CN-121985440-A - Intelligent power adjustment method and system for induction cooker based on cookware impedance identification

CN121985440ACN 121985440 ACN121985440 ACN 121985440ACN-121985440-A

Abstract

The invention belongs to the technical field of intelligent power regulation of induction cookers, and particularly relates to an intelligent power regulation method and system of an induction cooker based on cookware impedance identification. The method comprises the steps of outputting a micropower testing signal with gradually changed frequency in a pot detection stage, constructing an impedance-frequency curve according to the micropower testing signal, carrying out dynamic temperature compensation on impedance parameters, identifying the type of the pot, inquiring a power mapping database to obtain an optimal power control strategy, predicting an impedance change trend in a heating process, and calculating a power adjustment instruction to drive an inverter circuit to work by integrating real-time deviation and prediction deviation. The intelligent control system realizes accurate identification of cookers, optimal power matching due to cooker application and advanced smoothing intelligent control, and remarkably improves universality, safety, energy efficiency and cooking effect of the induction cooker.

Inventors

HU ZHIGANG
ZHAO ZHIYONG
Pan Gangxue

Assignees

广东沃尔姆斯电器有限公司

Dates

Publication Date: 20260505
Application Date: 20260203

Claims (9)

1. The intelligent power adjustment method for the induction cooker based on the pan impedance identification is characterized by comprising the following steps of: S1, controlling an electromagnetic oven to output a micropower test signal with gradually changed frequency to a heating coil in a pot detection stage, and synchronously collecting voltage signals and current signals at two ends of the coil under each frequency; S2, constructing an impedance-frequency curve of the cooker based on the acquired voltage signals and current signals, and extracting equivalent impedance parameters corresponding to working frequency points and broad-spectrum characteristic parameters for representing curve forms from the impedance-frequency curve; S3, collecting the temperature of the heating coil or the bottom of the cooker in real time, and carrying out temperature drift compensation on the equivalent impedance parameter and the broad-spectrum characteristic parameter by utilizing a preset impedance-temperature mapping relation to obtain a normalized impedance parameter; s4, inputting the normalization parameters into a pre-trained fusion recognition model, and recognizing a pan type recognition result of the pan; s5, inquiring a preset power mapping database according to the identified pan type, and acquiring an optimal impedance parameter target interval corresponding to the pan and an associated optimal power control strategy; S6, in the heating process, acquiring impedance parameter time sequence data of the pot after temperature drift compensation, and inputting the impedance parameter time sequence data into a state predictor to predict the change trend of the impedance parameter; And S7, comprehensively comparing and calculating the current real-time normalized impedance parameter, the optimal impedance parameter target interval and the change trend, and generating and executing a power adjusting instruction, wherein the power adjusting instruction is used for controlling the impedance parameter of the cooker to approach or keep in the target interval at a future moment.
2. The intelligent power adjustment method for an induction cooker based on pan impedance recognition according to claim 1, wherein in S2, the broad-spectrum characteristic parameters include a resonance frequency of the impedance-frequency curve, a quality factor Q value, an average slope in a predetermined frequency band, and an integral area under the curve.
3. The intelligent power adjustment method for induction cooker based on pan impedance recognition as set forth in claim 1, wherein in S4, the fusion recognition model comprises a first sub-model, a second sub-model and a meta learner, the first sub-model and the second sub-model are respectively used for learning single-frequency impedance parameters and broad-spectrum characteristic parameters, The meta learner is used for carrying out dynamic weighted fusion according to the output of the first sub model and the second sub model.
4. The intelligent power adjustment method for induction cooker based on pan impedance recognition as set forth in claim 3, wherein in S3, the meta-learner dynamically adjusts the output weights of the first sub-model and the second sub-model according to a set fusion weight formula according to the signal-to-noise ratio of the current input parameter and the current power output mode of the system, and specifically comprises the following steps: respectively calculating the confidence score of the first sub-model based on the single-frequency impedance parameter and the confidence score of the second sub-model based on the broad-spectrum characteristic parameter; Determining a mode coefficient according to whether the pot control system is in a transient high-power mode requiring quick response currently; Respectively calculating dynamic fusion weight values of the first sub-model and the second sub-model according to the two confidence scores and the mode coefficient; based on the dynamic fusion weight value, carrying out dynamic weighted fusion on the output of the first sub-model and the output of the second sub-model according to a set weight fusion formula, and outputting a pan category identification result.
5. The intelligent power adjustment method for the induction cooker based on the pan impedance recognition of claim 4, wherein in S3, the dynamic fusion weights of the first sub-model and the second sub-model are respectively calculated according to two confidence scores and mode coefficients, and the calculation formula comprises: ; ; In the formula, Dynamic fusion weight values of the first sub-model and the second sub-model respectively, Confidence scores for the first sub-model and the second sub-model respectively, As the mode coefficient(s), Is a preset preference adjustment constant for balancing the degree of influence of confidence and pattern on the final weight.
6. The intelligent power adjustment method for the induction cooker based on the pan impedance recognition of claim 1, wherein S7 comprises the following substeps: s71, calculating the real-time deviation between the current normalized impedance parameter and the optimal target interval; s72, calculating a prediction deviation of a future delta t moment based on the prediction trend output by the state predictor; s73, calculating and outputting a power adjustment quantity acted in advance through a feedforward-feedback control algorithm according to the calculated real-time deviation and the predicted deviation, and generating a power adjustment instruction according to the power adjustment quantity.
7. The intelligent power adjustment method for the induction cooker based on the pan impedance recognition of claim 1, wherein in S7, the method further comprises the following sub-steps: s74, calculating heating efficiency evaluation indexes based on input electric energy and a preset temperature rise model in real time in a complete heating period; s75, triggering an optimization flow when the heating efficiency evaluation index is continuously lower than a historical optimal efficiency theoretical threshold value of the corresponding pan type, wherein the optimization flow comprises incremental training of the state predictor by using impedance parameter time sequence data of the current period, and updating model parameters of the state predictor; The optimization flow also comprises the steps of analyzing the impedance parameter corresponding to the actual optimal efficiency point in the current period, and fine-tuning the optimal impedance parameter target interval and the power control strategy of the cooker category in the power mapping database.
8. The intelligent power adjustment method for an induction cooker based on pan impedance recognition as set forth in claim 7, wherein in S74, the calculation process of the heating efficiency evaluation index comprises: in a heating period, acquiring the instantaneous input voltage and the instantaneous input current of an induction cooker inverter circuit, and calculating the input electric energy in the calculation period according to an electric energy integral formula; calculating estimated Joule heating power transmitted to the cooker by the heating coil in the heating period according to a Joule formula according to the resistance component in the normalized impedance parameter; Constructing a boiler temperature rise model based on energy conservation and a thermodynamic model, inputting estimated Joule heat power into the boiler temperature rise model, and outputting theoretical temperature rise of the boiler in the heating period; Acquiring temperature change of the cookware or the stove surface or carrying out inverse operation based on the impedance-temperature mapping relation, and solving real temperature rise of the cookware in a heating period; and calculating the ratio of the theoretical temperature rise to the actual temperature rise, and taking the ratio as a heating efficiency evaluation index of a heating period.
9. An intelligent power adjusting system of an induction cooker based on pan impedance recognition, which is applied to an intelligent power adjusting method of an induction cooker based on pan impedance recognition as set forth in any one of claims 1 to 8, and is characterized in that the system comprises: The signal generation and acquisition module is used for controlling the induction cooker to output micropower test signals with gradually changed frequencies to the heating coil in the pot detection stage, and synchronously acquiring voltage signals and current signals at two ends of the coil under each frequency; The impedance spectrum analysis module is used for constructing an impedance-frequency curve of the cooker for the voltage signal and the current signal, and calculating equivalent impedance parameters and spectrum characteristic parameters; The temperature acquisition module is used for acquiring the temperature of the heating coil or the bottom of the pan according to the control instruction; The pot identification module is used for identifying the type of the pot according to a preset fusion identification model and acquiring an optimal impedance parameter target interval corresponding to the pot and an associated optimal power control strategy according to the type of the pot; The main control module is used for performing temperature compensation according to the acquired data of the temperature acquisition module, predicting the variation trend of the impedance parameter of the pot, calculating the real-time deviation and the predicted deviation, and calculating and outputting a power adjustment instruction according to a feedforward-feedback control algorithm; And the response driving module is used for responding to the power adjustment instruction to drive the induction cooker inverter circuit to work.

Description

Intelligent power adjustment method and system for induction cooker based on cookware impedance identification Technical Field The invention belongs to the technical field of intelligent power regulation of induction cookers, and particularly relates to an intelligent power regulation method and system of an induction cooker based on cookware impedance identification. Background The heating efficiency and safety of the induction cooker are dependent on the dynamic matching between the output energy and the electromagnetic and thermal characteristics of the cooker, and the control system of the induction cooker in the prior art mostly relies on single apparent electrical parameters such as current, voltage amplitude, resonance frequency offset and the like to detect the cooker. This approach essentially performs a coarse "feature screening" that can only distinguish between ferromagnetic and non-ferromagnetic materials, for example. However, practical kitchen ware environments are complex, and electromagnetic properties of cookware of different materials (such as 430 stainless steel and 304 stainless steel), different structures (single-layer, composite bottom and coated), and different sizes and shapes are quite different. The accurate distinguishing model cannot be built only by one or two macroscopic parameters, so that the recognition rate is low and the misjudgment rate is high when the system faces diversified modern cookers, and the unreliability of basic recognition buries hidden danger for subsequent power control; because the system cannot know the accurate electromagnetic information (such as equivalent impedance and loss angle) of the cookware, the power output of the cookware usually depends on preset and limited fixed power curves or a general PID algorithm based on simple temperature feedback. The control mode of the one-knife cutting ignores the difference of the optimal heat conversion efficiency points of different cookers. For example, for high resistance cookware, excessive current may cause overheating of the coil and reduced efficiency, and for low inductance cookware, energy may not be efficiently coupled. The result shows that the heating efficiency fluctuates greatly, the cooking effect (such as the heating speed and the temperature uniformity) is unpredictable, and the user demands of differentiation of 'slow stewing with small fire' and 'stir-frying with large fire' and the like cannot be responded finely. Moreover, parameters such as resistivity of the cookware (especially metal) can change obviously with the rise of temperature, and the equivalent impedance is not constant. The prior system generally ignores the key dynamic factor, and the identification model and the control parameters are solidified at normal temperature. Once heating begins, the "identity" of the cookware has actually drifted, but the system still uses the initial, failed model to make judgment and output, resulting in gradual deviation of power control from the optimal state, and the phenomena of proper power in the early stage, sudden drop in efficiency in the later stage or control instability. Disclosure of Invention In order to solve the problems in the prior art, the invention provides an intelligent power adjustment method and system for an induction cooker based on cookware impedance identification, which solve the systematic problems of inaccurate identification, low energy efficiency and mismatch in the heating process caused by rough power control and incapability of adapting to dynamic changes of electromagnetic characteristics of cookware in the heating process due to static cookware identification by relying on a single electric parameter in the conventional induction cooker. The intelligent power regulation method of the induction cooker based on the pan impedance identification comprises the following steps: S1, controlling an electromagnetic oven to output a micropower test signal with gradually changed frequency to a heating coil in a pot detection stage, and synchronously collecting voltage signals and current signals at two ends of the coil under each frequency; S2, constructing an impedance-frequency curve of the cooker based on the acquired voltage signals and current signals, and extracting equivalent impedance parameters corresponding to working frequency points and broad-spectrum characteristic parameters for representing curve forms from the impedance-frequency curve; S3, collecting the temperature of the heating coil or the bottom of the cooker in real time, and carrying out temperature drift compensation on the equivalent impedance parameter and the broad-spectrum characteristic parameter by utilizing a preset impedance-temperature mapping relation to obtain a normalized impedance parameter; s4, inputting the normalization parameters into a pre-trained fusion recognition model, and recognizing a pan type recognition result of the pan; s5, inquiring a preset power mapping database ac