Control method for a heating device and heating device

Abstract

This invention provides a control method and a heating device for a heating apparatus. The heating device includes a cavity for placing a substance to be processed and an electromagnetic wave generating system for generating electromagnetic waves within the cavity to heat the substance. The control method includes: a reference determination step: determining the remaining heating time and at least one frequency change reference; a frequency matching step: if a preset frequency tuning condition is met, controlling the electromagnetic wave generating system to adjust the frequency of the electromagnetic waves it generates to meet the preset matching condition; and a time correction step: dynamically correcting the remaining heating time based on the position of the cumulative frequency difference of the preset number of frequency adjustments in the frequency matching step relative to at least one frequency change reference, so as to reduce the adverse effects caused by inaccurate initial determination of the remaining heating time, so that the heating of the substance to be processed is accurately stopped at the state desired by the user, ensuring the nutritional quality of the substance to be processed and facilitating subsequent processing by the user.

Description

Technical Field

[0001] This invention relates to the field of food processing, and in particular to a control method and heating device for an electromagnetic wave heating device. Background Technology

[0002] During the freezing process, the quality of food is preserved; however, frozen food needs to be thawed before processing or consumption. To improve thawing efficiency and ensure thawing quality, electromagnetic wave heating devices are typically used to thaw food.

[0003] However, because electromagnetic waves thaw quickly, an excessively long thawing time can lead to severe over-thawing and deterioration of food quality; conversely, an excessively short thawing time can result in incomplete thawing, potentially requiring secondary thawing and affecting subsequent handling by the user. Properly controlling thawing time has always been a technical challenge that those skilled in the art have sought to solve. Summary of the Invention

[0004] One objective of the first aspect of the present invention is to overcome at least one technical defect in the prior art and provide a control method for a heating device.

[0005] A further objective of the first aspect of the present invention is to improve the accuracy of the end of thawing.

[0006] Another further objective of the first aspect of the present invention is to reduce unnecessary energy consumption.

[0007] A second aspect of the present invention is to provide an electromagnetic wave heating device.

[0008] According to a first aspect of the present invention, a control method for a heating device is provided, the heating device comprising a cavity for placing a workpiece and an electromagnetic wave generating system for generating electromagnetic waves within the cavity to heat the workpiece, wherein the control method comprises:

[0009] Reference determination steps: Determine the remaining heating time and at least one frequency variation reference;

[0010] Frequency matching step: If the preset frequency tuning conditions are met, the electromagnetic wave generating system is controlled to adjust the frequency of the electromagnetic waves it generates in order to meet the preset matching conditions.

[0011] Time correction step: The remaining heating time is dynamically corrected based on the position of the cumulative frequency difference of the frequency adjustment of the preset number of times in the frequency matching step relative to the at least one frequency change reference.

[0012] Optionally, in the reference determination step, the number of frequency variation references is one; and

[0013] In the time correction step, the remaining heating time is corrected based on the magnitude of the cumulative frequency difference relative to the frequency change reference.

[0014] Optionally, in the time correction step, if the cumulative frequency difference is greater than the frequency change reference, the remaining heating time is extended; and / or

[0015] In the time correction step, if the cumulative frequency difference is less than the frequency change reference, the remaining heating time is shortened.

[0016] Optionally, during the time correction step, the power of the electromagnetic waves generated by the electromagnetic wave generating system remains unchanged.

[0017] Optionally, the control method further includes:

[0018] Heating termination step: If the cumulative frequency difference of the preset number of frequency adjustments in the frequency matching step is less than the termination frequency difference threshold, the electromagnetic wave generating system is controlled to stop working; wherein,

[0019] The termination frequency difference threshold is less than any one of the at least one frequency variation references.

[0020] Optionally, the following step is included before the benchmark determination step:

[0021] Initial frequency determination step: Determine the initial frequency for heating the object to be treated based on the reflection parameters of the electromagnetic wave generating system; wherein,

[0022] In the reference determination step, the remaining heating time and the at least one frequency change reference are determined based on the initial frequency.

[0023] Optionally, the initial frequency determination step further includes:

[0024] Reference frequency determination steps: Control the electromagnetic wave generating system to adjust the frequency of the electromagnetic wave it generates within a preset candidate frequency range according to a preset first step length, obtain the reflection parameters corresponding to each frequency generated by the electromagnetic wave generating system, and determine the reference frequency based on the reflection parameters.

[0025] The optimal frequency determination step involves controlling the electromagnetic wave generating system to adjust the frequency of the generated electromagnetic waves within a selected frequency range according to a preset second step size, obtaining the reflection parameters corresponding to each frequency generated by the electromagnetic wave generating system, and determining the optimal frequency as the initial frequency based on the reflection parameters; wherein,

[0026] The selected frequency range is based on the reference frequency and is within a range of frequencies with the absolute value of the first step length as the radius; and

[0027] The absolute value of the second step length is less than the absolute value of the first step length.

[0028] Optionally, in the frequency matching step, the single frequency difference before and after frequency adjustment is calculated, and the single frequency difference of the most recent preset number of times is stored; and

[0029] The cumulative frequency difference is the sum of the single frequency differences over the preset number of times.

[0030] Optionally, in the frequency matching step, the frequency after this frequency adjustment and the frequency within a preset number of times before the frequency adjustment are stored; and

[0031] The cumulative frequency difference is the absolute value of the difference between the frequency before the frequency adjustment a preset number of times and the frequency after the current frequency adjustment.

[0032] According to a second aspect of the present invention, a heating device is provided, comprising:

[0033] The cavity is used to hold the object to be processed;

[0034] An electromagnetic wave generating system for generating electromagnetic waves within the cavity to heat the object to be processed; and

[0035] The controller is configured to perform any of the control methods described above.

[0036] This invention dynamically corrects the remaining heating time based on the position of the cumulative frequency difference of the preset frequency adjustment during the heating process relative to one or more frequency change references. This reduces the adverse effects caused by inaccurate initial determination of the remaining heating time, ensuring that the heating of the object to be processed stops precisely at the state desired by the user. This guarantees the nutritional quality of the object and facilitates subsequent processing by the user. As a result, the heating device of this invention can operate under different environmental conditions and achieve better heating results.

[0037] Furthermore, the present invention simultaneously determines whether heating is complete based on the remaining heating time and the termination frequency difference threshold, which can further prevent the object to be processed from being overheated. Especially when thawing food, it can keep the thawed food in good shape, making it easier to cut and process, thus improving the user experience.

[0038] Furthermore, the present invention first uses a larger step size to search and determine a reference frequency to represent the approximate position of the optimal frequency, and then uses a smaller step size to search and determine the optimal frequency in the vicinity of the reference frequency. Compared with the prior art method of determining the optimal frequency by traversing all frequencies, the efficiency of determining the optimal frequency can be improved by several times, thereby reducing the total heating time, reducing unnecessary energy consumption, and improving the energy efficiency ratio of the heating device.

[0039] The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0040] The following sections will describe some specific embodiments of the invention in detail by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0041] Figure 1 This is a schematic structural diagram of a heating device according to an embodiment of the present invention;

[0042] Figure 2 yes Figure 1 A schematic structural diagram of the controller;

[0043] Figure 3 This is a schematic flowchart of a control method for a heating device according to an embodiment of the present invention;

[0044] Figure 4 This is a schematic detailed flowchart of a control method for a heating device according to an embodiment of the present invention. Detailed Implementation

[0045] Figure 1 This is a schematic structural diagram of a heating device 100 according to an embodiment of the present invention. See also Figure 1 The heating device 100 may include a cavity 110, an electromagnetic wave generating system, and a controller 140.

[0046] The cavity 110 may include a cylinder and a door. The cylinder can be used to place the object to be processed 150. The door can be used to open and close the loading and unloading port of the cylinder.

[0047] The cylinder and door may be equipped with electromagnetic shielding features to reduce electromagnetic leakage. The cylinder may be made of metal and grounded.

[0048] The electromagnetic wave generating system may be at least partially disposed within or accessible to the cavity 110 to generate electromagnetic waves within the cavity 110, thereby heating the object to be processed 150.

[0049] The electromagnetic wave generating system may include an electromagnetic wave generating module 120, a radiating antenna 130 electrically connected to the electromagnetic wave generating module 120, and a power supply for supplying power to the electromagnetic wave generating module 120.

[0050] The electromagnetic wave generating module 120 can be configured to generate electromagnetic wave signals. The radiating antenna 130 can be disposed within the cavity 110 to generate electromagnetic waves within the cavity 110. The electromagnetic wave generating module 120 may include a variable frequency source and a power amplifier.

[0051] Figure 2 yes Figure 1 A schematic structural diagram of the controller 140. See also... Figure 2 The controller 140 may include a processing unit 141 and a storage unit 142. The storage unit 142 stores a computer program 143, which, when executed by the processing unit 141, is used to implement the control method of the embodiments of the present invention.

[0052] The processing unit 141 can be configured to, during the heating process, if the preset frequency modulation conditions are met, control the electromagnetic wave generation module 120 to adjust the frequency of the electromagnetic wave signal it generates in order to meet the preset matching conditions and improve the heating efficiency.

[0053] The preset frequency modulation condition can be that the reflection parameter of the electromagnetic wave generating system is greater than the preset frequency modulation reflection threshold, so as to ensure heating efficiency.

[0054] The preset matching condition can be that the reflection parameters of the electromagnetic wave generating system reach a concave inflection point and the reflection parameters are less than a preset matching reflection threshold. The processing unit 141 can be configured to control the electromagnetic wave generating module 120 to generate an electromagnetic wave signal at the frequency corresponding to this inflection point, so as to further improve the heating efficiency. The matching reflection threshold can be less than the frequency modulation reflection threshold.

[0055] The reflection parameter can be the return loss S11. The reflection parameter can also be the reflected power value of the electromagnetic wave signal reflected back to the electromagnetic wave generation module 120.

[0056] Specifically, the processing unit 141 may be configured to determine the remaining heating time and at least one frequency change reference, and during the heating process, dynamically correct the remaining heating time relative to the position of the cumulative frequency difference Δf adjusted according to a preset number of frequencies relative to the at least one frequency change reference. In this invention, at least one refers to one, two, or more than two frequency change references.

[0057] The heating device of the present invention dynamically corrects the remaining heating time based on the position of the cumulative frequency difference Δf of the preset frequency adjustment during the heating process relative to one or more frequency change references. This reduces the adverse effects caused by inaccurate initial determination of the remaining heating time, so that the heating of the object to be processed stops precisely at the state expected by the user, ensuring the nutritional quality of the object to be processed and facilitating subsequent processing by the user. This allows the heating device of the present invention to work under different environmental conditions and achieve better heating results.

[0058] In some embodiments, the processing unit 141 may be configured to calculate the single frequency difference before and after frequency adjustment while controlling the electromagnetic wave generation module 120 to adjust the frequency of the electromagnetic wave signal it generates, and store the single frequency difference of the most recent preset number of times in the storage unit 142.

[0059] The single frequency difference can be the absolute value of the difference between the frequency before and after frequency adjustment. The cumulative frequency difference Δf can be the sum of the single frequency differences for the corresponding number of times, thereby reducing the requirements on the controller 140.

[0060] In other embodiments, the processing unit 141 may be configured to store the frequency before frequency adjustment and the frequency within a preset number of times after frequency adjustment while controlling the electromagnetic wave generation module 120 to adjust the frequency of the electromagnetic wave signal it generates.

[0061] The cumulative frequency difference Δf can be the absolute value of the difference between the frequency before frequency adjustment and the frequency after this frequency adjustment before a preset number of times, so as to reduce the number of calculations.

[0062] In some embodiments, the number of frequency variation references may be one. The processing unit 141 may be configured to correct the remaining heating time based on the magnitude of the cumulative frequency difference Δf relative to the frequency variation reference B, so as to simplify the control program while ensuring the accuracy of heating termination.

[0063] Specifically, the processing unit 141 can be configured to extend the remaining heating time when the cumulative frequency difference Δf is greater than the frequency change reference B, in order to avoid incomplete heating. For example, the remaining heating time can be extended by 1% to 5%, such as 1%, 2%, 3%, or 5%.

[0064] The processing unit 141 can be configured to shorten the remaining heating time to avoid overheating when the cumulative frequency difference Δf is less than the frequency change reference B. Exemplarily, the remaining heating time can be shortened by 1% to 5%, for example, 1%, 2%, 3%, or 5%.

[0065] The processing unit 141 can also be configured to maintain the remaining heating time unchanged when the cumulative frequency difference Δf is equal to the frequency change reference B.

[0066] In other embodiments, there may be two frequency variation references, namely a first frequency variation reference and a second frequency variation reference. The first frequency variation reference may be greater than the second frequency variation reference.

[0067] The processing unit 141 can be configured to extend the remaining heating time when the cumulative frequency difference Δf is greater than the first frequency change reference; shorten the remaining heating time when the cumulative frequency difference Δf is less than the second frequency change reference; and maintain the remaining heating time unchanged when the cumulative frequency difference Δf is greater than or equal to the second frequency change reference and less than or equal to the first frequency change reference.

[0068] In some other embodiments, the number of frequency variation references may be three, namely a first frequency variation reference, a second frequency variation reference, and a third frequency variation reference. The first frequency variation reference may be larger than the second frequency variation reference, and the second frequency variation reference may be larger than the third frequency variation reference.

[0069] The processing unit 141 can be configured to extend the remaining heating time by a first ratio and a second ratio respectively when the cumulative frequency difference Δf is greater than a first frequency change reference and greater than a second frequency change reference but less than or equal to the first frequency change reference; the processing unit 141 can also be configured to shorten the remaining heating time by a first ratio and a second ratio respectively when the cumulative frequency difference Δf is less than a third frequency change reference and greater than or equal to the third frequency change reference but less than the second frequency change reference; and maintain the remaining heating time unchanged when the cumulative frequency difference Δf is equal to the second frequency change reference. The first ratio can be greater than the second ratio.

[0070] In some embodiments, the processing unit 141 may also be configured to maintain the power of the electromagnetic wave signal generated by the electromagnetic wave generation module 120 at the same time as correcting the remaining heating time, so as to ensure heating efficiency.

[0071] In some embodiments, the processing unit 141 may be configured to control the electromagnetic wave generating module 120 to stop operating when the cumulative frequency difference Δf is less than the termination frequency difference threshold F, in order to prevent overheating. The termination frequency difference threshold F may be less than any one of at least one frequency variation reference.

[0072] In some embodiments, the processing unit 141 may be configured to control the electromagnetic wave generation module 120 to generate an electromagnetic wave signal with a frequency of the minimum value of a preset candidate frequency range and stop calculating the cumulative frequency difference when the preset matching conditions are not met at each frequency, so as to ensure the heating effect.

[0073] The alternative frequency range can be 350MHz to 500MHz. Furthermore, the alternative frequency range can be 400MHz to 460MHz to further improve the temperature uniformity of the material to be processed 150.

[0074] In some further embodiments, the processing unit 141 may be configured to determine the initial frequency of the object to be heated 150 based on the reflection parameters of the electromagnetic wave generating system at the start of heating, and to determine the remaining heating time, at least one frequency change reference, and termination frequency difference threshold F based on the initial frequency, so as to reduce user operation and save electrical components.

[0075] Processing unit 141 may be further configured to first determine a reference frequency f for searching the optimal frequency. b Then determine the optimal frequency f suitable for heating. g As an initial frequency, to improve the determination of the optimal frequency f g This improves efficiency, thereby reducing the total heating time, minimizing unnecessary energy consumption, and increasing the energy efficiency ratio of the heating device 100.

[0076] Specifically, the processing unit 141 can be configured to control the electromagnetic wave generating module 120 to adjust the frequency of the electromagnetic wave signal it generates within a preset candidate frequency range according to a preset first step length W1, acquire the reflection parameters corresponding to each frequency generated by the electromagnetic wave generating module 120, and determine the reference frequency f based on the reflection parameters. b .

[0077] Processing unit 141 can be further configured to control electromagnetic wave generation module 120 to adjust the frequency of the electromagnetic wave signal it generates within a selected frequency range according to a preset second step size W2, acquire the reflection parameters corresponding to each frequency generated by electromagnetic wave generation module 120, and determine the optimal frequency f based on the reflection parameters. g The selected frequency range can be based on the reference frequency f. b The frequency is defined within a radius, with the absolute value of the first step length W1 as its value. The absolute value of the second step length W2 can be less than the absolute value of the first step length W1.

[0078] In some embodiments, the processing unit 141 may be configured to search for a reference frequency f in increments from the minimum value of a self-selected frequency range. b That is, the length W1 of the first step is a positive number.

[0079] In some alternative embodiments, processing unit 141 may also be configured to search for a reference frequency f by decreasing the maximum value of the self-selected frequency range. b That is, the length W1 of the first step is negative.

[0080] The absolute value of the first step length W1 can be 5MHz to 10MHz. For example, 5MHz, 7MHz, or 10MHz.

[0081] The absolute value of the second step size W2 can be 1MHz to 2MHz. For example, 1MHz, 1.5MHz, or 2MHz.

[0082] In some further embodiments, the processing unit 141 may be configured to control the electromagnetic wave generating module 120 to adjust the frequency of the electromagnetic wave signal it generates until the reflection parameter is less than a preset first reflection threshold S1, and to determine the frequency at which the reflection parameter is less than the first reflection threshold S1 as the reference frequency f. b That is, the processing unit 141 determines the frequency at which the reflection parameter first appears to be less than the first reflection threshold S1 as the reference frequency f. b In order to obtain the accurate optimal frequency f g At the same time, further improve the determination of the optimal frequency f g Efficiency.

[0083] In some further embodiments, the processing unit 141 may be configured to control the electromagnetic wave generating module 120 to stop working and issue visual and / or auditory signals to prompt the user of the fault when the reflection parameter corresponding to each frequency generated by the electromagnetic wave generating module 120 is greater than the first reflection threshold S1, so as to avoid poor heating effect and damage to the electromagnetic wave generating system.

[0084] In some further embodiments, the processing unit 141 may be configured to control the electromagnetic wave generating module 120 to adjust the frequency of the electromagnetic wave signal it generates until the reflection parameter reaches a concave inflection point, and determine the frequency corresponding to this inflection point as the optimal frequency f. g To achieve excellent heating results. Optimal frequency f g The reflection parameters corresponding to both the previous and subsequent frequencies are greater than the optimal frequency f. g The reflection parameters (i.e., the inflection point with a concave shape).

[0085] In some further embodiments, the processing unit 141 may be configured to first determine the reference frequency f. b The search direction is either towards high frequency or low frequency. Further, in this search direction, the electromagnetic wave generating module 120 is controlled to adjust the frequency of the electromagnetic wave signal it generates until the reflection parameter reaches a concave inflection point.

[0086] In some exemplary embodiments, the processing unit 141 may be configured to acquire the frequency relative to the reference frequency f. b The frequency greater than the second step size W2 and the frequency greater than the reference frequency f b For reflection parameters with frequencies less than the second step size W2, compare the magnitudes of the two reflection parameters and determine the direction corresponding to the frequency with the smaller reflection parameter as the search direction.

[0087] In some further embodiments, the processing unit 141 may be configured to operate at an optimal frequency f. gIf the corresponding reflection parameter is greater than the preset second reflection threshold S2, the electromagnetic wave generating module 120 stops working and sends a visual and / or auditory signal to indicate a fault, in order to avoid poor heating effect. The second reflection threshold S2 can be less than the first reflection threshold S1.

[0088] In some further embodiments, the processing unit 141 may be configured to operate at an optimal frequency f. g Greater than or equal to the preset minimum frequency threshold f i And less than or equal to the preset maximum frequency threshold f a In the case of optimal frequency f g Determine the remaining heating time.

[0089] The processing unit 141 can be configured to count down based on the remaining heating time, and when the remaining heating time is 0, control the electromagnetic wave generating module 120 to stop working and issue visual and / or auditory signals to indicate that heating is complete.

[0090] In some further embodiments, the processing unit 141 may be configured to operate at an optimal frequency f. g Less than the minimum frequency threshold f i In the event of an overload, the electromagnetic wave generating module 120 stops working and sends visual and / or auditory signals to indicate overload, in order to avoid excessive heating time.

[0091] Minimum frequency threshold f i The difference between the minimum value and the minimum value of the candidate frequency range can be 15% to 30% of the difference between the maximum and minimum values ​​of the candidate frequency range. For example, 15%, 20%, 25%, or 30%.

[0092] In some further embodiments, the processing unit 141 may be configured to operate at an optimal frequency f. g Greater than the maximum frequency threshold f a In the event of an unloaded condition, the electromagnetic wave generating module 120 will stop working and issue visual and / or auditory signals to indicate that it is not in use, in order to avoid damaging the electromagnetic wave generating system.

[0093] The maximum value of the candidate frequency range and the maximum frequency threshold f a The difference can be 5% to 10% of the difference between the maximum and minimum values ​​in the candidate frequency range. For example, 5%, 7%, 8%, or 10%.

[0094] It should be noted that the heating device 100 of the present invention is particularly suitable for use in refrigerators, and the cavity 110 can be installed in a storage compartment of the refrigerator.

[0095] Figure 3 This is a schematic flowchart of a control method for a heating device 100 according to an embodiment of the present invention. See also Figure 3The control method for the heating device 100 of the present invention may include the following steps:

[0096] Reference determination step (step S302): Determine the remaining heating time and at least one frequency variation reference;

[0097] Frequency matching step (step S304): If the preset frequency tuning conditions are met, the electromagnetic wave generating system is controlled to adjust the frequency of the electromagnetic waves it generates in order to meet the preset matching conditions.

[0098] Time correction step (step S306): Dynamically correct the remaining heating time based on the position of the cumulative frequency difference Δf of the preset number of frequency adjustments in the frequency matching step relative to at least one frequency change reference.

[0099] The control method of the present invention dynamically corrects the remaining heating time based on the position of the cumulative frequency difference Δf of the preset frequency adjustment during the heating process relative to one or more frequency change references. This reduces the adverse effects caused by inaccurate initial determination of the remaining heating time, ensuring that the heating of the object to be processed stops precisely at the state desired by the user. This guarantees the nutritional quality of the object to be processed and facilitates subsequent processing by the user. It also enables the heating device of the present invention to work under different environmental conditions and achieve better heating results.

[0100] The preset frequency modulation condition can be that the reflection parameter of the electromagnetic wave generating system is greater than the preset frequency modulation reflection threshold, so as to ensure heating efficiency.

[0101] The preset matching condition can be that the reflection parameters of the electromagnetic wave generating system reach a concave inflection point and the reflection parameters are less than a preset matching reflection threshold, so that the electromagnetic wave generating module 120 generates an electromagnetic wave signal at the frequency corresponding to that inflection point, further improving heating efficiency. The matching reflection threshold can be less than the frequency modulation reflection threshold.

[0102] The reflection parameter can be the return loss S11. The reflection parameter can also be the reflected power value of the electromagnetic wave signal reflected back to the electromagnetic wave generation module 120.

[0103] In some embodiments, the frequency matching step may further include: calculating the single frequency difference before and after frequency adjustment, and storing the single frequency difference of the most recent preset number of times in the storage unit 142.

[0104] The single frequency difference can be the absolute value of the difference between the frequency before and after frequency adjustment. The cumulative frequency difference Δf can be the sum of the single frequency differences for the corresponding number of times, thereby reducing the requirements on the controller 140.

[0105] In other embodiments, the frequency matching step may further include: storing the frequency after frequency adjustment and the frequency within a preset number of times before frequency adjustment.

[0106] The cumulative frequency difference Δf can be the absolute value of the difference between the frequency before frequency adjustment and the frequency after this frequency adjustment before a preset number of times, so as to reduce the number of calculations.

[0107] In some embodiments, the number of frequency variation references in the reference determination step may be one. The time correction step may correct the remaining heating time based on the magnitude of the cumulative frequency difference Δf relative to the frequency variation reference B, thereby simplifying the control program while ensuring the accuracy of heating termination.

[0108] Specifically, the time correction step may include: if the cumulative frequency difference Δf is greater than the frequency change reference B, extending the remaining heating time to avoid incomplete heating. For example, the remaining heating time may be extended by 1% to 5%, such as 1%, 2%, 3%, or 5%.

[0109] If the cumulative frequency difference Δf is less than the frequency change reference B, the remaining heating time is shortened to avoid overheating. For example, the remaining heating time can be shortened by 1% to 5%, such as 1%, 2%, 3%, or 5%.

[0110] If the cumulative frequency difference Δf is equal to the frequency change reference B, the remaining heating time remains unchanged.

[0111] In other embodiments, the number of frequency variation references in the reference determination step may be two, namely a first frequency variation reference and a second frequency variation reference. The first frequency variation reference may be greater than the second frequency variation reference.

[0112] The time correction steps may include: if the cumulative frequency difference Δf is greater than the first frequency change reference, extending the remaining heating time; if the cumulative frequency difference Δf is less than the second frequency change reference, shortening the remaining heating time; if the cumulative frequency difference Δf is greater than or equal to the second frequency change reference and less than or equal to the first frequency change reference, maintaining the remaining heating time unchanged.

[0113] In some other embodiments, the number of frequency change references in the reference determination step can be three, namely a first frequency change reference, a second frequency change reference, and a third frequency change reference. The first frequency change reference can be greater than the second frequency change reference, and the second frequency change reference can be greater than the third frequency change reference.

[0114] The time correction steps may include: if the cumulative frequency difference Δf is greater than the first frequency change reference and greater than the second frequency change reference but less than or equal to the first frequency change reference, extending the remaining heating time according to the first ratio and the second ratio respectively; if the cumulative frequency difference Δf is less than the third frequency change reference and greater than or equal to the third frequency change reference but less than the second frequency change reference, shortening the remaining heating time according to the first ratio and the second ratio respectively; if the cumulative frequency difference Δf is equal to the second frequency change reference, maintaining the remaining heating time unchanged. The first ratio may be greater than the second ratio.

[0115] In some embodiments, during the time correction step, the power of the electromagnetic wave signal generated by the electromagnetic wave generation module 120 remains constant to ensure heating efficiency.

[0116] In some embodiments, the control method of the present invention may further include a heating termination step. The heating termination step may control the electromagnetic wave generating module 120 to stop operating when the accumulated frequency difference Δf is less than a termination frequency difference threshold F, in order to prevent overheating. The termination frequency difference threshold F may be less than any one of at least one frequency variation reference.

[0117] In some embodiments, if each electromagnetic wave signal generated by the electromagnetic wave generation module 120 does not meet the preset matching conditions in the frequency matching step, the electromagnetic wave generation module 120 is controlled to generate an electromagnetic wave signal with a frequency of the minimum value of the preset candidate frequency range and the calculation of the cumulative frequency difference is stopped to ensure the heating effect.

[0118] The alternative frequency range can be 350MHz to 500MHz. Furthermore, the alternative frequency range can be 400MHz to 460MHz to further improve the temperature uniformity of the material to be processed 150.

[0119] In some further embodiments, the control method of the present invention may further include an initial frequency determination step before the frequency matching step. The initial frequency determination step may determine the initial frequency of the heated object 150 based on the reflection parameters of the electromagnetic wave generating system at the start of heating.

[0120] The reference determination step can determine the remaining heating time, at least one frequency change reference, and the termination frequency difference threshold F based on the initial frequency, thereby reducing user operations and saving electrical components.

[0121] The initial frequency determination step may further include a reference frequency determination step and an optimal frequency determination step, first determining a reference frequency f used to search for the optimal frequency. b Then determine the optimal frequency f suitable for heating. g As an initial frequency, to improve the determination of the optimal frequency f g This improves efficiency, thereby reducing the total heating time, minimizing unnecessary energy consumption, and increasing the energy efficiency ratio of the heating device 100.

[0122] The reference frequency determination step may include: controlling the electromagnetic wave generating module 120 to adjust the frequency of the electromagnetic wave signal it generates within a preset candidate frequency range according to a preset first step length W1; obtaining the reflection parameters corresponding to each frequency generated by the electromagnetic wave generating module 120; and determining the reference frequency f based on the reflection parameters. b .

[0123] The optimal frequency determination step may include: controlling the electromagnetic wave generating module 120 to adjust the frequency of the electromagnetic wave signal it generates within a selected frequency range according to a preset second step size W2, obtaining the reflection parameters corresponding to each frequency generated by the electromagnetic wave generating module 120, and determining the optimal frequency f based on the reflection parameters. g As the initial frequency.

[0124] The selected frequency range can be based on the reference frequency f. b The frequency is defined within a radius, with the absolute value of the first step length W1 as its value. The absolute value of the second step length W2 can be less than the absolute value of the first step length W1.

[0125] In some embodiments, when determining the reference frequency f b During the process, the minimum value of the self-selected frequency range can be incremented to search for the reference frequency f. b That is, the length W1 of the first step is a positive number.

[0126] In some alternative embodiments, when determining the reference frequency f b During the process, the maximum value of the self-selected frequency range can be decreased to search for the reference frequency f. b That is, the length W1 of the first step is negative.

[0127] The absolute value of the first step length W1 can be 5MHz to 10MHz. For example, 5MHz, 7MHz, or 10MHz.

[0128] The absolute value of the second step size W2 can be 1MHz to 2MHz. For example, 1MHz, 1.5MHz, or 2MHz.

[0129] In some further embodiments, in the optimal frequency determination step, the electromagnetic wave generating module 120 adjusts the frequency of the electromagnetic wave signal it generates until the reflection parameter is less than a preset first reflection threshold S1, and the frequency at which the reflection parameter is less than the first reflection threshold S1 is determined as the reference frequency f. b That is, the frequency at which the reflection parameter first appears to be less than the first reflection threshold S1 is determined as the reference frequency f. b In order to obtain the accurate optimal frequency f g At the same time, further improve the determination of the optimal frequency f g Efficiency.

[0130] In some further embodiments, if the reflection parameter corresponding to each frequency generated by the electromagnetic wave generating module 120 is greater than the first reflection threshold S1, the electromagnetic wave generating module 120 is controlled to stop working and emits visual and / or auditory signals to prompt the user of the fault, so as to avoid poor heating effect and damage to the electromagnetic wave generating system.

[0131] In some further embodiments, in the optimal frequency determination step, the electromagnetic wave generating module 120 adjusts the frequency of the electromagnetic wave signal it generates until the reflection parameter reaches a concave inflection point, and the frequency corresponding to this inflection point is determined as the optimal frequency f. g To achieve excellent heating results. Optimal frequency f g The reflection parameters corresponding to both the previous and subsequent frequencies are greater than the optimal frequency f. g The reflection parameters (i.e., the inflection point with a concave shape).

[0132] In some further embodiments, in the optimal frequency determination step, the self-reference frequency f can be determined first. b The search direction is either towards high frequency or low frequency. Further, in this search direction, the electromagnetic wave generating module 120 is controlled to adjust the frequency of the electromagnetic wave signal it generates until the reflection parameter reaches a concave inflection point.

[0133] For example, the frequency f can be obtained separately from the reference frequency. b The frequency greater than the second step size W2 and the frequency greater than the reference frequency f b For reflection parameters with frequencies less than the second step size W2, compare the magnitudes of the two reflection parameters and determine the direction corresponding to the frequency with the smaller reflection parameter as the search direction.

[0134] In some further embodiments, if the optimal frequency f g If the corresponding reflection parameter is greater than the preset second reflection threshold S2, the electromagnetic wave generating module 120 will stop working and issue a visual and / or auditory signal to indicate a fault, in order to avoid poor heating effect. The second reflection threshold S2 may be less than the first reflection threshold S1.

[0135] In some further embodiments, if the optimal frequency f g Greater than or equal to the preset minimum frequency threshold f i And less than or equal to the preset maximum frequency threshold f a According to the optimal frequency f g Determine the remaining heating time, and when the remaining heating time is 0, control the electromagnetic wave generating module 120 to stop working and emit visual and / or auditory signals to indicate that heating is complete.

[0136] In some further embodiments, if the optimal frequency f gLess than the minimum frequency threshold f i The electromagnetic wave generating module 120 is controlled to stop working and emits visual and / or auditory signals to indicate overload, so as to avoid excessive heating time.

[0137] Minimum frequency threshold f i The difference between the minimum value and the minimum value of the candidate frequency range can be 15% to 30% of the difference between the maximum and minimum values ​​of the candidate frequency range. For example, 15%, 20%, 25%, or 30%.

[0138] In some further embodiments, if the optimal frequency f g Greater than the maximum frequency threshold f a The electromagnetic wave generating module 120 is controlled to stop working and emits visual and / or auditory signals to indicate that it is unloaded, so as to avoid damaging the electromagnetic wave generating system.

[0139] The maximum value of the candidate frequency range and the maximum frequency threshold f a The difference can be 5% to 10% of the difference between the maximum and minimum values ​​in the candidate frequency range. For example, 5%, 7%, 8%, or 10%.

[0140] Figure 4 This is a schematic detailed flowchart of a control method for a heating device 100 according to an embodiment of the present invention (in... Figure 4 In the text, "Y" indicates "yes"; "N" indicates "no". See also... Figure 4 The control method for the heating device 100 of the present invention may include the following detailed steps, wherein the number of frequency change references is one:

[0141] Step S402: Control the electromagnetic wave generating system to adjust the frequency of the electromagnetic wave it generates within a preset candidate frequency range according to the preset first step length W1, and obtain the reflection parameters corresponding to each frequency generated by the electromagnetic wave generating system.

[0142] Step S404: Determine if there is a reflection parameter less than the first reflection threshold S1. If yes, proceed to step S406; otherwise, proceed to step S408.

[0143] Step S406: Determine the reference frequency f corresponding to the frequency of the first reflection parameter that is less than the first reflection threshold S1. b Execute step S410.

[0144] Step S408: Control the electromagnetic wave generating system to stop working and issue visual and / or auditory signals to indicate the fault.

[0145] Step S410: Within the selected frequency range, control the electromagnetic wave generating system to adjust the frequency of the generated electromagnetic waves according to the second step size W2, obtain the reflection parameters corresponding to each frequency until the reflection coefficient shows a concave inflection point, and determine the frequency corresponding to the inflection point as the optimal frequency f. g .

[0146] Step S412: Based on the optimal frequency f g Determine the remaining heating time, frequency change baseline B, and termination frequency difference threshold F.

[0147] Step S414: If the preset frequency modulation conditions are met, control the electromagnetic wave generating system to adjust the frequency of the electromagnetic waves it generates to meet the preset matching conditions, calculate the single frequency difference between the frequency after adjustment and before adjustment, and store the single frequency difference of the most recent preset number of times.

[0148] Step S416: Calculate the cumulative frequency difference Δf for a preset number of frequency adjustments based on the stored single frequency difference, and determine whether the cumulative frequency difference Δf is greater than the frequency change reference B. If yes, proceed to step S418; otherwise, proceed to step S420.

[0149] Step S418: Extend the remaining heating time. Proceed to step S424.

[0150] Step S420: Determine whether the cumulative frequency difference Δf is less than the frequency change reference B. If yes, proceed to step S422; if no, proceed to step S424.

[0151] Step S422: Shorten the remaining heating time. Proceed to step S424.

[0152] Step S424: Determine whether the cumulative frequency difference Δf is less than the termination frequency difference threshold F. If yes, proceed to step S426; otherwise, proceed to step S428.

[0153] Step S426: Control the electromagnetic wave generating system to stop working.

[0154] Step S428: Determine if the remaining heating time is equal to 0. If yes, proceed to step S426; otherwise, return to step S414.

[0155] Therefore, those skilled in the art should recognize that although numerous exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Thus, the scope of the present invention should be understood and construed as covering all such other variations or modifications.

Claims

1. A control method for a heating device, the heating device comprising a cavity for placing a workpiece and an electromagnetic wave generating system for generating electromagnetic waves within the cavity to heat the workpiece, wherein, The control method includes: Reference determination steps: Determine the remaining heating time and at least one frequency variation reference; Frequency matching step: If the preset frequency tuning conditions are met, the electromagnetic wave generating system is controlled to adjust the frequency of the electromagnetic waves it generates in order to meet the preset matching conditions. Time correction step: The remaining heating time is dynamically corrected based on the position of the cumulative frequency difference of the preset number of frequency adjustments in the frequency matching step relative to the position of the at least one frequency change reference; wherein, In the time correction step, if the cumulative frequency difference is greater than the frequency change reference, the remaining heating time is extended; and / or In the time correction step, if the cumulative frequency difference is less than the frequency change reference, the remaining heating time is shortened.

2. The control method according to claim 1, wherein, In the reference determination step, the number of frequency variation references is one.

3. The control method according to claim 1, wherein, During the time correction step, the power of the electromagnetic waves generated by the electromagnetic wave generating system remains unchanged.

4. The control method according to claim 1 further includes: Heating termination step: If the cumulative frequency difference of the preset number of frequency adjustments in the frequency matching step is less than the termination frequency difference threshold, the electromagnetic wave generating system is controlled to stop working; wherein, The termination frequency difference threshold is less than any one of the at least one frequency variation references.

5. The control method according to claim 1, wherein, The following steps are included prior to the baseline determination step: Initial frequency determination step: Determine the initial frequency for heating the object to be treated based on the reflection parameters of the electromagnetic wave generating system; wherein, In the reference determination step, the remaining heating time and the at least one frequency change reference are determined based on the initial frequency.

6. The control method according to claim 5, wherein, The initial frequency determination step further includes: Reference frequency determination steps: Control the electromagnetic wave generating system to adjust the frequency of the electromagnetic wave it generates within a preset candidate frequency range according to a preset first step length, obtain the reflection parameters corresponding to each frequency generated by the electromagnetic wave generating system, and determine the reference frequency based on the reflection parameters. The optimal frequency determination step involves controlling the electromagnetic wave generating system to adjust the frequency of the generated electromagnetic waves within a selected frequency range according to a preset second step size, obtaining the reflection parameters corresponding to each frequency generated by the electromagnetic wave generating system, and determining the optimal frequency as the initial frequency based on the reflection parameters; wherein, The selected frequency range is based on the reference frequency and is within a range of frequencies with the absolute value of the first step length as the radius; and The absolute value of the second step length is less than the absolute value of the first step length.

7. The control method according to claim 1, wherein, In the frequency matching step, the single frequency difference before and after frequency adjustment is calculated, and the single frequency difference of the most recent preset number is stored. and The cumulative frequency difference is the sum of the single frequency differences over the preset number of times.

8. The control method according to claim 1, wherein, In the frequency matching step, the frequency after this frequency adjustment and the frequency within a preset number of times before the frequency adjustment are stored; and The cumulative frequency difference is the absolute value of the difference between the frequency before the frequency adjustment a preset number of times and the frequency after the current frequency adjustment.

9. A heating device, comprising: A cavity, used to hold the object to be processed; An electromagnetic wave generating system is used to generate electromagnetic waves within the cavity to heat the object to be processed. as well as A controller configured to perform the control method as described in any one of claims 1-8.

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