Heating device and control method for heating device

Abstract

The invention provides a heating device and a control method for the heating device. The heating device comprises a cavity, an electromagnetic wave generation module and a matching module. The matching module comprises a first matching unit and a first calibration unit. The first matching unit comprises at least one matching branch circuit which can be independently switched on and off. The first calibration unit comprises at least one calibration branch circuit which can be independently switched on and off and is arranged to be connected with the first matching unit in parallel. Wherein the first calibration unit is fixed in the process of heating the to-be-treated object. The control method comprises the following steps: sequentially determining an optimal on-off combination of a first matching unit corresponding to each on-off combination of a first calibration unit; calculating an impedance difference value between each optimal on-off combination and a preset standard on-off combination, and comparing to obtain a minimum impedance difference value; and under the condition that the minimum impedance difference value is smaller than a preset difference value threshold value, fixing the on-off combination of the calibration unit corresponding to the minimum impedance difference value in impedance matching before the next operation calibration test step.

Description

Technical Field

[0001] The present invention relates to the field of food processing, and in particular to a heating device and a control method for the heating device. Background Art

[0002] During the freezing process of food, the quality of the food is maintained, but the frozen food needs to be thawed before processing or eating. In order to facilitate users to thaw the food, an electromagnetic wave heating device is usually used to thaw the food.

[0003] Thawing food with an electromagnetic wave heating device is not only fast and efficient, but also reduces the loss of food nutrients. However, there are inevitably some errors in the processing and assembly of the heating device, and device loss or container changes may occur during use, resulting in the matching module being unable to accurately complete impedance matching, or even unable to cover the impedance changes of the food during the entire heating process, seriously affecting the user experience. Summary of the invention

[0004] An object of the first aspect of the present invention is to overcome at least one technical defect in the prior art and provide an electromagnetic wave heating device.

[0005] A further object of the first aspect of the present invention is to ensure the heating effect of the heating device during long-term use.

[0006] An object of the second aspect of the present invention is to provide a control method for a heating device.

[0007] A further object of the second aspect of the present invention is to simplify the control procedure.

[0008] According to a first aspect of the present invention, there is provided a heating device, comprising:

[0009] A cavity, used for placing objects to be processed;

[0010] an electromagnetic wave generating module, configured to generate an electromagnetic wave signal for heating the object to be processed; and

[0011] A matching module, configured to adjust the load impedance of the electromagnetic wave generating module by adjusting its own impedance; wherein the matching module comprises:

[0012] A first matching unit, comprising at least one matching branch that can be independently switched on and off; and

[0013] The first calibration unit includes at least one calibration branch that can be independently switched on and off, and is arranged to be connected in parallel with the first matching unit; wherein,

[0014] The first calibration unit remains fixed during the process of heating the object to be processed.

[0015] The heating device of the present invention is provided with a calibration unit connected in parallel with the matching unit, which is only used for adjusting the adjustable range of the matching unit as a whole and does not directly participate in impedance matching by adjusting its own impedance. While ensuring the heating effect of the heating device during long-term use and reducing the failure rate, there is no need to make adaptability improvements to the control method related to impedance matching, thereby reducing R&D costs.

[0016] Optionally, one end of the first matching unit is connected in series between the electromagnetic wave generating module and the cavity, and the other end is grounded.

[0017] The heating device of the present invention connects the calibration unit in parallel with the matching unit which is grounded in series. That is, when the heating device is only provided with one calibration unit, the calibration unit is preferably connected in parallel with the matching unit which is grounded in series. This reduces the production cost and improves the ability of the calibration unit to adjust the matching range of the matching unit, so that the heating device can operate stably and efficiently.

[0018] Optionally, the matching module further includes:

[0019] A second matching unit has one end connected in series with the electromagnetic wave generating module, and the other end connected in series between the first matching unit and the cavity.

[0020] The heating device of the present invention adopts a matching module circuit with a specific series-parallel relationship, which is not only simple and reliable, but also can more flexibly and accurately adjust the load impedance of the electromagnetic wave generating module, further increasing the adjustable range of the matching circuit and ensuring the heating effect on the object to be treated.

[0021] Optionally, the second matching unit includes at least one matching branch that can be independently switched on and off, and at least one fixed branch connected in parallel with the at least one matching branch, and an impedance value of the fixed branch is fixed.

[0022] The heating device of the present invention has a fixed branch with a fixed impedance value and a matching branch that can be independently switched in series between the electromagnetic wave generating module and the cavity, which further increases the adjustable range of the matching circuit and improves the safety of the matching module.

[0023] Optionally, the matching branch includes a fixed value capacitor and a switch; and

[0024] The first matching unit has a plurality of matching branches, the capacitance values ​​of the fixed-value capacitors of the plurality of matching branches are different, and the capacitance value of each fixed-value capacitor is 2 times or 1 / 2 times the capacitance value of another fixed-value capacitor.

[0025] The capacitance value of each fixed-value capacitor of the matching unit of the heating device of the present invention is 2 times or 1 / 2 times the capacitance value of another fixed-value capacitor, so that the difference between two adjacent numbers of the combination number of the first matching units sorted by impedance value is the same, which improves the matching accuracy of the processed object and reduces the difference in heating effect of different foods.

[0026] According to a second aspect of the present invention, a control method for a heating device is provided, wherein the heating device is a heating device according to any one of the above descriptions; wherein the control method comprises:

[0027] Calibration test step: sequentially determining the optimal on-off combination of the first matching unit corresponding to each on-off combination of the first calibration unit;

[0028] Difference comparison step: calculating the impedance difference between each of the optimal on-off combination and the preset standard on-off combination, and comparing to obtain the minimum impedance difference;

[0029] Matching calibration step: when the minimum impedance difference is less than a preset difference threshold, fixing the on-off combination of the calibration unit corresponding to the minimum impedance difference in the impedance matching before the next execution of the calibration test step.

[0030] The control method of the present invention selects the fixed on-off combination of the calibration unit by calculating the impedance difference between each optimal on-off combination of the first matching unit and the preset standard on-off combination, so that the heating device is close to the ideal state of the design and the best heating effect is achieved.

[0031] Optionally, the control method further includes:

[0032] In the case where the impedance value of each of the optimal on-off combinations in the calibration test step is greater than a preset calibration impedance threshold, the difference comparison step is performed.

[0033] The control method of the present invention makes an initial judgment on whether the error of the current heating device is within the calibrable range according to the impedance value of the optimal on-off combination itself, thereby avoiding excessive repetition and complexity of the control program, and reducing the time required for calibration while ensuring the calibration effect.

[0034] Optionally, the control method further includes:

[0035] When the impedance value of any of the optimal on-off combinations in the calibration test step is less than a preset fault impedance threshold, the calibration test step is terminated.

[0036] When the control method of the present invention finds that the impedance value of the optimal on-off combination is less than the preset fault impedance threshold, it determines that the error of the current heating device is large, and the problem cannot be well improved by using the calibration unit, so the calibration test step is terminated in advance, reducing the user's waiting time and unnecessary energy loss.

[0037] Optionally, the control method further includes:

[0038] When it is determined in the calibration test step that the impedance value of the first optimal on-off combination is less than or equal to a preset calibration impedance threshold and greater than or equal to a preset fault impedance threshold, the difference comparison step is skipped and the on-off combination of the calibration unit corresponding to the optimal on-off combination is fixed.

[0039] When the control method of the present invention determines that the impedance value of the first optimal on-off combination is between the calibration impedance threshold and the fault impedance threshold, the on-off combination of the corresponding calibration unit is directly fixed, which simplifies the control procedure and improves the user experience while ensuring the calibration effect.

[0040] Optionally, the first matching unit has a plurality of matching branches, wherein the control method further includes:

[0041] A number acquisition step: acquiring a pre-configured number set of the first matching unit, the number set including a combination number of an on-off combination of the at least one matching branch, the combination number corresponding to the impedance value of the first matching unit; wherein determining each of the optimal on-off combinations in the calibration test step includes:

[0042] Benchmark determination step: determining a first test group in the number set, the first test group including a plurality of combination numbers whose impedance values ​​differ by a preset first difference value, controlling the on and off of the corresponding matching branch according to the first test group and obtaining a reflection parameter corresponding to each combination number in the first test group, and determining a first matching benchmark in the first test group according to the reflection parameter;

[0043] Optimal test step: determining a second test group based on the first matching benchmark, the second test group including the first matching benchmark and a plurality of combination numbers whose impedance values ​​differ by a preset second difference value, controlling the on and off of the corresponding matching branch according to the second test group and obtaining the reflection parameter corresponding to each combination number in the second test group, and determining the second matching benchmark or the optimal combination number in the second test group according to the reflection parameter; wherein,

[0044] The second difference is less than the first difference; and

[0045] In the difference comparison step, the impedance difference is the difference between the optimal combination number and the standard combination number corresponding to the preset standard on-off combination.

[0046] The control method of the present invention obtains the optimal combination number by numbering the on-off combinations of the first matching unit and narrowing the test range by successively determining one or more matching benchmarks. Not only can the impedance value be compared and calculated through the combination number itself, thereby simplifying the control procedure, but also, compared with the control method in the prior art that needs to determine the reflection parameters of the on-off combination one by one to compare the optimal on-off combination, the time used to determine the optimal on-off combination can be greatly shortened, thereby reducing energy loss.

[0047] Based on the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art will become more aware of the above and other objects, advantages and features of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0049] Figure 1 is a schematic structural diagram of a heating device according to an embodiment of the present invention;

[0050] Figure 2 yes Figure 1 A schematic structural diagram of the controller;

[0051] Figure 3 yes Figure 1 A schematic structural diagram of the matching module;

[0052] Figure 4 is a schematic flow chart of a control method for first impedance matching of a heating device according to an embodiment of the present invention;

[0053] Figure 5 is a schematic flow chart of a control method for re-impedance matching of a heating device according to an embodiment of the present invention;

[0054] Figure 6 is a schematic flow chart of a control method for matching calibration of a heating device according to an embodiment of the present invention;

[0055] Figure 7 is a detailed flow chart of a heating control method for a heating device according to an embodiment of the present invention;

[0056] Figure 8 yes Figure 7 The continuation of

[0057] Fig. 9is a detailed flow chart of a calibration control method for a heating device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0058] Figure 1 is a schematic structural diagram of a heating device 100 according to an embodiment of the present invention. Figure 1 The heating device 100 may include a cavity 110 for placing an object to be processed 160 , an electromagnetic wave generating module 120 , a radiation antenna 130 , a matching module 140 and a controller 150 .

[0059] The radiation antenna 130 may be disposed in the cavity 110 . The electromagnetic wave generating module 120 may be configured to generate an electromagnetic wave signal and be electrically connected to the radiation antenna 130 to generate electromagnetic waves in the cavity 110 , thereby heating the object 160 to be processed in the cavity 110 .

[0060] The matching module 140 can be connected in series between the electromagnetic wave generating module 120 and the cavity 110 capacitor or in parallel at both ends of the cavity 110 capacitor, and is configured to adjust the load impedance of the electromagnetic wave generating module 120 by adjusting its own impedance to achieve load matching and improve heating efficiency.

[0061] Figure 2 yes Figure 1 Schematic diagram of the structure of the controller 150. Figure 2 The controller 150 may include a processing unit 151 and a storage unit 152. The storage unit 152 stores a computer program 153, and the computer program 153 is used to implement the control method of the embodiment of the present invention when executed by the processing unit 151.

[0062] Figure 3 yes Figure 1 Schematic diagram of the matching module 140. Figure 1 , the matching module 140 may include a first matching unit 141 .

[0063] The first matching unit 141 may include a plurality of matching branches that can be independently switched on and off, so as to form different impedance values ​​through different on-off combinations.

[0064] Each matching branch of the first matching unit 141 may include a fixed value capacitor C X and a switch K X .

[0065] exist Figure 3 In the illustrated embodiment, the first matching unit 141 may include a fixed value capacitor C X1 ~C X5 and respectively switch C X1 ~C X5 Switch K X1 ~KX5 Five matching branches are formed.

[0066] In some embodiments, the processing unit 151 can be configured to obtain a number set of preconfigured first matching units 141, determine a first matching reference in the number set, and further determine a second matching reference or an optimal combination number based on the first matching reference for heating the object 160 to be processed.

[0067] The number set may include combination numbers of on-off combinations of multiple matching branches, and the combination numbers correspond to the impedance value of the first matching unit 141, so that the relevant calculation of the impedance value can be performed through the combination numbers themselves.

[0068] The processing unit 151 may be specifically configured to determine a first test group in the number set, control the on and off of the corresponding matching branch according to the first test group and obtain the reflection parameter corresponding to each combination number in the first test group, and determine the first matching reference in the first test group according to the reflection parameter to shorten the time for determining the optimal on and off combination. The impedance values ​​of the multiple combination numbers of the first test group may differ by a preset first difference.

[0069] Exemplarily, the reflection parameter may be the return loss S11. The smallest value of the return loss S11 indicates the best on-off combination; the largest value of the return loss S11 indicates the worst on-off combination.

[0070] The processing unit 151 may be specifically configured to determine a second test group based on the first matching reference, control the on and off of the corresponding matching branch according to the second test group, obtain the reflection parameter corresponding to each combination number in the second test group, and determine the second matching reference or the optimal combination number in the second test group according to the reflection parameter. The impedance values ​​of the plurality of combination numbers of the second test group and the first matching reference may differ by a preset second difference, and the second difference is smaller than the first difference.

[0071] The test range of the second test group may be a range with the first matching reference as the center and the first difference as the radius.

[0072] It is understandable that, whether to determine the second matching reference or even the third matching reference can be selected according to the number of on-off combinations of the first matching unit 141 to further narrow the test range and finally obtain the optimal combination number.

[0073] The fixed value capacitor C of the first matching unit 141 X1 ~C X5The capacitance value of each fixed-value capacitor is 2 times or 1 / 2 times the capacitance value of another fixed-value capacitor, so that the difference between two adjacent numbers of the combination number of the first matching unit 141 sorted by impedance value is the same, which improves the matching accuracy of the object to be processed 160 and reduces the limitation of the specific values ​​of the first difference and the second difference preset in the design.

[0074] For example, 1 / 4C X3 ≈1 / 2C X2 ≈C X1 ≈C U As shown in Table 1, K X1 ~K X3 The on / off state and corresponding capacitance value and combination number, where “√” indicates on and “×” indicates off.

[0075] Table 1

[0076]

[0077]

[0078] For some single fixed-value capacitors with large current values ​​when in the on state, they can be replaced by connecting multiple fixed-value capacitors with smaller capacitance values ​​in parallel and using linkage switches that simultaneously turn on or off the multiple fixed-value capacitors. For example, C X5 and K X5 .

[0079] In some further embodiments, the matching module 140 may further include a second matching unit 142 .

[0080] The second matching unit 142 may include a plurality of matching branches that can be independently switched on and off, so as to form different impedance values ​​through different on-off combinations.

[0081] Each matching branch of the second matching unit 142 may include a fixed value capacitor C Y and a switch K Y .

[0082] exist Figure 3 In the illustrated embodiment, the second matching unit 142 may include a fixed value capacitor C Y1 ~C Y3 and respectively switch C Y1 ~C Y3 Switch K Y1 ~K Y3 Three matching branches are formed.

[0083] The processing unit 151 may be configured to traverse the on-off combinations of the second matching unit 142 based on a combination number when acquiring the reflection parameter corresponding to the combination number of the first matching unit 141, and record the optimal reflection parameter in the on-off combination of the second matching unit 142 as the reflection parameter of the combination number. That is, first fix a combination number of the test group, and then test the reflection parameters of each on-off combination of the second matching unit 142 corresponding to the combination number one by one, so as to facilitate the determination of the matching benchmark and the optimal combination number, and reduce the amount of data stored at the same time.

[0084] In some further embodiments, the processing unit 151 may be configured to record the better reflection parameter and the corresponding second matching unit 142 configuration for each combination number when traversing the on-off combination of the second matching unit 142, until the best reflection parameter and the second matching unit 142 configuration for the combination number are determined. That is, only the best reflection parameter and the corresponding second matching unit 142 configuration for each combination number are recorded, so as to facilitate the subsequent formal heating of the object to be processed 160 according to the best configuration of the matching module 140, and further simplify the control program.

[0085] In some further embodiments, the processing unit 151 may be configured to control the on / off of the corresponding matching branch according to the optimal combination number and the corresponding second matching unit 142 configuration after confirming the optimal combination number, and start to efficiently heat the object to be processed 160 .

[0086] The heating power of the electromagnetic wave generating module 120 after confirming the optimal combination number is greater than the test power before confirming the optimal combination number, so as to reduce the influence of impedance matching on the heating effect.

[0087] In some further embodiments, the second matching unit 142 may be connected in series between the electromagnetic wave generating module 120 and the cavity 110 .

[0088] One end of the first matching unit 141 can be connected in series between the second matching unit 142 and the cavity 110 and the other end can be grounded, so as to flexibly and accurately adjust the load impedance of the electromagnetic wave generating module 120 and obtain the optimal combination number efficiently and accurately.

[0089] The second matching unit 142 may further include at least one fixed branch connected in parallel with the matching branch, and the impedance value of the fixed branch is fixed, for example, C Y , so as to improve the security of the matching module 140.

[0090] In some further embodiments, the number of matching branches of the first matching unit 141 may be greater than the number of matching branches of the second matching unit 142, so as to improve the testing efficiency of the optimal combination number as a whole and reduce the determination error of the optimal combination number.

[0091] In some further embodiments, the processing unit 151 can be configured to determine whether a preset tuning condition is met during the heating process, and when the preset tuning condition is met, control the matching module 140 to adjust the on-off state of the matching branch (i.e., the impedance of the matching module 140 itself) so that the reflection parameters of the matching module 140 meet the preset matching conditions, thereby ensuring the heating efficiency of the object to be processed 160.

[0092] The tuning condition may include that the reflection parameter is inferior to a preset matching threshold, or that the continuous time for satisfying the tuning condition is greater than a preset matching time threshold. That is, when any of the conditions of "the reflection parameter is inferior to the preset matching threshold" and "the continuous time for satisfying the tuning condition is greater than the preset matching time threshold" is met, the control matching module 140 is adjusted to achieve re-matching.

[0093] The matching condition may include that the reflection parameter is optimal. Alternatively, the matching condition may include that the reflection parameter is better than a matching threshold.

[0094] The tuning condition for the entire heating procedure starting from receiving the heating instruction may further include receiving the heating instruction, and the matching condition may further include first adjusting the reflection parameter of the matching module 140 to be optimal.

[0095] The processing unit 151 may be configured to repeatedly acquire corresponding reflection parameters based on the current configuration of the matching module 140 during the heating process until the tuning condition is met.

[0096] In some further embodiments, the processing unit 151 can be configured to redetermine a new matching combination number within the range where the impedance value of the number set is less than the optimal combination number or the previous matching combination number during the re-matching process, so as to ensure the absorption rate of the object to be processed 160 to electromagnetic waves and shorten the time required for re-matching.

[0097] In some embodiments, the processing unit 151 can be configured to determine the weight of the object to be processed 160 and / or the control parameters for heating the object to be processed 160 according to the optimal combination number after determining the optimal combination number, so as to reduce production costs, avoid error superposition of too much detection data, and achieve precise heating of the object to be processed 160.

[0098] In some embodiments, the processing unit 151 may be configured to adjust the control parameters of heating the object to be processed 160 according to the impedance range of the first matching unit 141 that meets the matching condition for a preset number of times, so as to reduce or solve the problem of uneven temperature or overheating of the object to be processed 160 after heating due to factors such as insufficient user experience or system errors. The impedance range may be the range of the corresponding combination number.

[0099] Exemplarily, if the preset number of times is four, the first impedance range should be the range between the optimal combination number initially determined and the matching combination numbers of the first three re-matchings.

[0100] In some further embodiments, the processing unit 151 may be configured to determine a reference threshold for correcting the control parameter according to the optimal combination number, so as to know the difference between the current state and the designed state of the object to be processed 160 .

[0101] In some further embodiments, the control parameter may include a remaining heating time. The reference threshold may include a first correction threshold and a first termination threshold.

[0102] The processing unit 151 may be configured to increase a preset first extension percentage based on the current remaining heating time when the impedance extreme difference is greater than the first correction threshold, so as to prevent the object to be processed 160 from being overcooled.

[0103] The processing unit 151 may be configured to reduce a preset first shortening percentage based on the current remaining heating time to avoid overheating of the object 160 to be processed when the impedance extreme difference is less than or equal to the first correction threshold and greater than the first termination threshold.

[0104] The processing unit 151 can be configured to control the electromagnetic wave generating module 120 to stop working or complete heating according to the current remaining heating time when the impedance difference is less than or equal to the first termination threshold, so as to avoid energy waste or poor heating effect.

[0105] In some further embodiments, the control parameter may include heating power.The reference threshold may include a second correction threshold and a second termination threshold.

[0106] The processing unit 151 may be configured to reduce a preset reduction percentage based on the current heating power when the impedance extreme difference is greater than the second correction threshold, so as to improve the temperature uniformity of the object to be processed 160 .

[0107] The processing unit 151 may be configured to maintain the current heating power unchanged when the impedance extreme difference is less than or equal to the second correction threshold and greater than the second termination threshold.

[0108] The processing unit 151 may be configured to control the electromagnetic wave generating module 120 to stop working when the impedance difference is less than or equal to the second termination threshold, so as to prevent the object to be processed 160 from being overheated.

[0109] The processing unit 151 may be further configured to increase a preset second extension percentage based on the current remaining heating time while reducing the heating power, so as to avoid insufficient heating of the object 160 to be processed.

[0110] In some further embodiments, the processing unit 151 may be configured to first adjust the remaining heating time according to the first correction threshold and the first termination threshold during the first operating time, and then adjust the heating power second operating time according to the second correction threshold and the second termination threshold until the heating is completed, so as to simplify the control procedure while ensuring the heating effect. The first operating time may be positively correlated with the initially determined remaining heating time.

[0111] In some embodiments, the matching module 140 may further include a first calibration unit 143 connected in parallel with a matching unit.

[0112] The first calibration unit 143 may include at least one calibration branch that can be independently switched on and off. The first calibration unit 143 remains fixed during the heating process of the object to be processed 160, and is only used to adjust the adjustable range of the matching unit as a whole, and does not directly participate in impedance matching by adjusting its own impedance, that is, there is no need to improve the adaptability of the control method related to impedance matching, thereby ensuring the heating effect of the heating device 100 during long-term use.

[0113] In some further embodiments, the first calibration unit 143 may be connected in parallel with the first matching unit 141 to improve the ability of the calibration unit to adjust the matching range of the matching unit while reducing production costs.

[0114] Each calibration branch of the first calibration unit 143 may include a fixed value capacitor C Z and a switch K Z .

[0115] exist Figure 3 In the illustrated embodiment, the first calibration unit 143 may include a fixed value capacitor C Z1 ~C Z2 and respectively switch C Z1 ~C Z2 Switch K Z1 ~K Z2 Two calibration branches are formed.

[0116] The second matching unit 142 and the first calibration unit 143 may also be numbered like the first matching unit 141 .

[0117] In some further embodiments, the processing unit 151 can be configured to determine in sequence the optimal on-off combination of the first matching unit 141 corresponding to each on-off combination of the first calibration unit 143, calculate the impedance difference between each optimal on-off combination and a preset standard on-off combination, and compare the minimum impedance difference. When the minimum impedance difference is less than a preset difference threshold, the on-off combination of the calibration unit corresponding to the minimum impedance difference is fixed to make the heating device 100 close to the ideal designed state and achieve the best heating effect.

[0118] The impedance difference may be a difference between the optimal combination number and a standard combination number corresponding to a preset standard on-off combination.

[0119] In some further embodiments, the processing unit 151 may be configured to terminate calibration when the impedance value of any optimal on-off combination is less than a preset fault impedance threshold during the process of determining the optimal on-off combination, thereby reducing user waiting time and unnecessary energy loss.

[0120] In some further embodiments, the processing unit 151 can be configured to, in the process of determining the optimal on-off combination, directly fix the on-off combination of the calibration unit corresponding to the optimal on-off combination when it is determined that the impedance value of the first optimal on-off combination is less than or equal to a preset calibration impedance threshold and greater than or equal to a preset fault impedance threshold, thereby simplifying the control program while ensuring the calibration effect.

[0121] In some further embodiments, the processing unit 151 may be configured to calculate and compare impedance differences when the impedance value of each optimal on-off combination is greater than a preset calibration impedance threshold value during the process of determining the optimal on-off combination.

[0122] In the process of determining the optimal on-off combination of the first matching unit 141 corresponding to each on-off combination of the first calibration unit 143, the optimal on-off combination can be determined by first determining the matching reference to narrow the test range, which is the same method as the initial impedance matching, to improve calibration efficiency.

[0123] The first calibration unit 143 may further include a fixed branch connected in parallel with the calibration branch, and the impedance value of the fixed branch is fixed, for example, C Z , so as to improve the security of the matching module 140.

[0124] It should be noted that the calibration unit of the present invention is also applicable to a matching unit having only one matching branch; a calibration unit may also be provided for each matching unit.

[0125] In some embodiments, the matching module 140 may also include a fixed inductor L connected in series between the second matching unit 142 and the cavity 110, and one end of the first matching unit 141 is connected in series between the second matching unit 142 and the fixed inductor L to better achieve impedance matching between the electromagnetic wave generating module 120 and the cavity 110, and further improve the safety of the matching module 140.

[0126] Figure 4 is a schematic flow chart of a control method for first impedance matching of a heating device 100 according to an embodiment of the present invention. Figure 4 The control method for first impedance matching performed by the controller 150 of any of the above embodiments of the present invention may include the following steps:

[0127] Step S402 (number acquisition): acquiring a pre-configured number set of the first matching unit 141, the number set including combination numbers of on-off combinations of multiple matching branches, the combination number corresponding to the impedance value of the first matching unit 141;

[0128] Step S404 (benchmark determination): determine a first test group in the number set, the first test group includes a plurality of combination numbers whose impedance values ​​differ by a preset first difference value, control the on and off of the corresponding matching branch according to the first test group and obtain the reflection parameter corresponding to each combination number in the first test group, and determine the first matching benchmark in the first test group according to the reflection parameter;

[0129] Step S406 (optimal test): Based on the first matching benchmark, a second test group is determined, the second test group includes a first matching benchmark and multiple combination numbers whose impedance values ​​differ by a preset second difference, the on and off of the corresponding matching branches are controlled according to the second test group, and the reflection parameters corresponding to each combination number in the second test group are obtained, and the second matching benchmark or the optimal combination number is determined in the second test group according to the reflection parameters; wherein the second difference is smaller than the first difference.

[0130] The control method of the present invention obtains the optimal combination number by numbering the on-off combinations of the first matching unit 141, and by successively determining one or more matching benchmarks to narrow the test range. Not only can the impedance value be compared and calculated through the combination number itself, thereby simplifying the control procedure, but also, compared with the control method in the prior art that needs to determine the reflection parameters of the on-off combination one by one to compare the optimal on-off combination, the time used to determine the optimal on-off combination can be greatly shortened, the influence of impedance matching on the heating effect can be reduced, the heating efficiency can be improved, and the energy consumption can be reduced.

[0131] Exemplarily, the reflection parameter may be the return loss S11. The smallest value of the return loss S11 indicates the best on-off combination; the largest value of the return loss S11 indicates the worst on-off combination.

[0132] In the embodiment where the matching module 140 further includes the second matching unit 142, in the process of obtaining the reflection parameter corresponding to the combination number of the first matching unit 141 in the benchmark determination step and the optimal test step, the on-off combinations of the second matching unit 142 can be traversed based on a combination number, and the optimal reflection parameter in the on-off combination of the second matching unit 142 is recorded as the reflection parameter of the combination number. That is, a combination number of the test group is fixed first, and then the reflection parameter of each on-off combination of the second matching unit 142 corresponding to the combination number is tested one by one, so as to facilitate the determination of the matching benchmark and the optimal combination number, and reduce the amount of data stored at the same time.

[0133] In some further embodiments, in the benchmark determination step and the optimal test step, the more optimal reflection parameter of each combination number and the corresponding configuration of the second matching unit 142 may be recorded until the optimal reflection parameter of the combination number and the configuration of the second matching unit 142 are determined. That is, only the optimal reflection parameter of each combination number and the corresponding configuration of the second matching unit 142 are recorded, so as to facilitate the subsequent formal heating of the object to be processed 160 according to the optimal configuration of the matching module 140, and further simplify the control procedure.

[0134] In some embodiments, the control method of the present invention may further include, after the optimal test step:

[0135] Formal heating step: Control the on and off of the corresponding matching branch according to the optimal combination number and the corresponding second matching unit 142 configuration. The heating power of the formal heating step is greater than the test power of the reference determination step and the optimal test step to reduce the influence of impedance matching on the heating effect and improve the heating efficiency.

[0136] In some embodiments, the control method of the present invention further comprises, after the formal heating step:

[0137] Matching test step: obtaining corresponding reflection parameters based on the current configuration of the matching module 140;

[0138] Rematching step: When the preset tuning conditions are met, the matching module 140 is controlled to adjust its own impedance so that the reflection parameters of the matching module 140 meet the preset matching conditions, thereby ensuring the heating efficiency of the object 160 to be processed.

[0139] The tuning condition of the rematching step may include that the reflection parameter is inferior to a preset matching threshold, or that the continuous time for satisfying the tuning condition is greater than a preset matching time threshold. That is, when any of the conditions of "the reflection parameter is inferior to the preset matching threshold" and "the continuous time for satisfying the tuning condition is greater than the preset matching time threshold" is met, the control matching module 140 adjusts to achieve rematching.

[0140] The matching condition of the re-matching step may include that the reflection parameter is optimal. Alternatively, the matching condition of the re-matching step may include that the reflection parameter is better than a matching threshold.

[0141] The aforementioned benchmark determination step and optimal test step can be collectively referred to as an impedance matching step together with the rematching step. The tuning condition of the impedance matching step can also include receiving a heating instruction, and the matching condition can also include first adjusting the reflection parameters of the matching module 140 to be optimal.

[0142] In some further embodiments, in the rematching step, a new matching combination number can be re-determined within the range where the impedance value of the number set is less than the optimal combination number or the previous matching combination number to ensure the absorption rate of the object to be processed 160 to electromagnetic waves and shorten the time required for rematching.

[0143] In some embodiments, the control method of the present invention further comprises, after the optimal testing step:

[0144] Parameter initial determination step: determine the weight of the object 160 to be processed and / or the control parameters for heating the object 160 to be processed according to the optimal combination number, so as to reduce production costs, avoid error superposition of too much detection data, and achieve accurate heating of the object 160 to be processed.

[0145] Figure 5 is a schematic flow chart of a control method for re-impedance matching of a heating device 100 according to an embodiment of the present invention. Figure 5 The control method for re-impedance matching performed by the controller 150 of any of the above embodiments of the present invention may include the following steps:

[0146] Step S502 (impedance matching): when the preset tuning condition is met, the matching module 140 is controlled to adjust its own impedance so that the reflection parameter of the matching module 140 meets the preset matching condition;

[0147] Step S504 (parameter correction): adjusting the control parameters of heating the object to be processed 160 according to the impedance range of the first matching unit 141 that meets the matching condition for a preset number of times. The impedance range may be the range of the combination number.

[0148] The control method of the present invention adjusts the control parameters of the heating object 160 according to the impedance extreme difference that satisfies the matching conditions within a preset number of times of the matching unit with one end grounded, corrects the parameters initially determined for the heating, alleviates or solves the problem of uneven temperature or overcooling or overheating of the object 160 to be processed after heating due to factors such as insufficient user experience or system errors (such as insufficient accuracy of detection elements, insufficient initial parameter determination methods), is compatible with foods of various attribute parameters, and can avoid unexpected energy waste.

[0149] In some embodiments, in the parameter initialization step, the control method of the present invention further determines a reference threshold for correcting the control parameter according to the optimal combination number, so as to know the difference between the current state and the designed state of the object 160 to be processed.

[0150] In some further embodiments, the control parameter includes the remaining heating time, and the reference threshold includes a first correction threshold and a first termination threshold. The parameter correction step may include:

[0151] The first time correction step: when the impedance extreme difference is greater than the first correction threshold, the preset first extension percentage is increased on the basis of the current remaining heating time to avoid overcooling of the object 160 to be processed; when the impedance extreme difference is less than or equal to the first correction threshold and greater than the first termination threshold, the preset first shortening percentage is reduced on the basis of the current remaining heating time to avoid overheating of the object 160 to be processed; when the impedance extreme difference is less than or equal to the first termination threshold, the electromagnetic wave generating module 120 is controlled to stop working or complete heating according to the current remaining heating time to avoid energy waste or poor heating effect.

[0152] In some further embodiments, the control parameter includes heating power, and the reference threshold includes a second correction threshold and a second termination threshold. The parameter correction step may include:

[0153] Power correction steps: when the impedance extreme difference is greater than the second correction threshold, reduce the preset reduction percentage based on the current heating power to improve the temperature uniformity of the object to be processed 160; when the impedance extreme difference is less than or equal to the second correction threshold and greater than the second termination threshold, maintain the current heating power unchanged; when the impedance extreme difference is less than or equal to the second termination threshold, control the electromagnetic wave generating module 120 to stop working to avoid overheating of the object to be processed 160.

[0154] In some further embodiments, the parameter modification step may further include:

[0155] The second time correction step: while reducing the preset reduction percentage based on the current heating power, increasing the preset second extension percentage based on the current remaining heating time to avoid insufficient heating of the object 160 to be processed.

[0156] In some further embodiments, the first time correction step and the power correction step may respectively run a first running time and a second running time, wherein the first running time is positively correlated with the remaining heating time determined in the parameter initialization step.

[0157] The power correction step is run after the first time correction step is completed, so as to simplify the control program while ensuring the heating effect.

[0158] Figure 6 is a schematic flow chart of a control method for matching calibration of a heating device 100 according to an embodiment of the present invention. Figure 6 The control method for matching calibration performed by the controller 150 of any of the above embodiments of the present invention may include the following steps:

[0159] Step S602 (calibration test): sequentially determining the optimal on-off combination of the first matching unit 141 corresponding to each on-off combination of the first calibration unit 143;

[0160] Step S604 (difference comparison): calculating the impedance difference between each optimal on-off combination and the preset standard on-off combination, and comparing to obtain the minimum impedance difference;

[0161] Step S606 (matching calibration): when the minimum impedance difference is less than the preset difference threshold, the on-off combination of the calibration unit corresponding to the minimum impedance difference is fixed in the impedance matching before the next calibration test step is run.

[0162] The control method of the present invention selects a fixed on-off combination of the calibration unit by calculating the impedance difference between each optimal on-off combination of the first matching unit 141 and a preset standard on-off combination, so that the heating device 100 is close to the ideal state of the design and achieves the best heating effect.

[0163] In some further embodiments, the control method of the present invention performs a difference comparison step when the impedance value of each optimal on-off combination in the calibration test step is greater than a preset calibration impedance threshold value. That is, a preliminary judgment is made as to whether the error of the current heating device 100 is within the calibrable range based on the impedance value of the optimal on-off combination itself, thereby avoiding excessive repetition and complexity of the control procedure.

[0164] In some further embodiments, the control method of the present invention terminates the calibration test step when the impedance value of any optimal on-off combination of the calibration test step is less than a preset fault impedance threshold, thereby reducing the user's waiting time and unnecessary energy loss.

[0165] In some further embodiments, when the control method of the present invention determines in the calibration test step that the impedance value of the first optimal on-off combination is less than or equal to a preset calibration impedance threshold and greater than or equal to a preset fault impedance threshold, the difference comparison step is skipped and the on-off combination of the calibration unit corresponding to the optimal on-off combination is fixed, thereby simplifying the control procedure while ensuring the calibration effect.

[0166] In some further embodiments, the control method of the present invention may specifically adopt the same or similar steps as the reference determination step and the optimal test step to determine each optimal on-off combination in the calibration test step, so as to improve the calibration efficiency.

[0167] Figure 7 is a detailed flow chart of a heating control method for a heating device 100 according to an embodiment of the present invention; Figure 8 yes Figure 7 (In the accompanying drawings, "Y" means "yes"; "N" means "no"). Figure 7 and Figure 8 The heating control method for the heating device 100 of the present invention may specifically include the following steps:

[0168] Step S702: Determine whether a heating instruction is received. If yes, execute step S704; if no, repeat step S702.

[0169] Step S704 : obtaining a pre-configured number set of the first matching unit 141 , where the number set includes combination numbers of on-off combinations of a plurality of matching branches, and the combination numbers correspond to the impedance value of the first matching unit 141 .

[0170] Step S706: Determine a first test group in the number set, the first test group including multiple combination numbers whose impedance values ​​differ by a preset first difference, control the on and off of the corresponding matching branches according to the first test group and obtain the reflection parameters corresponding to each combination number in the first test group, and determine the first matching benchmark in the first test group according to the reflection parameters.

[0171] Step S708: Determine a second test group based on the first matching benchmark, the second test group including a first matching benchmark having an impedance value differing by a preset second difference and multiple combination numbers, control the on and off of the corresponding matching branches according to the second test group, obtain the reflection parameters corresponding to each combination number in the second test group, and determine the second matching benchmark or the optimal combination number in the second test group according to the reflection parameters.

[0172] Step S710: determining the remaining heating time, the correction threshold and the termination threshold according to the optimal combination number, and controlling the on and off of the corresponding matching branch according to the optimal combination number and the corresponding second matching unit 142 configuration.

[0173] Step S802: Obtain corresponding reflection parameters based on the current configuration of the matching module 140 .

[0174] Step S804: Determine whether the reflection parameter is greater than a preset matching threshold. If yes, execute step S808; if no, execute step S806.

[0175] Step S806: Determine whether the continuous time that the matching module 140 uses the current configuration is greater than a preset time threshold. If yes, execute step S808; if no, return to step S802.

[0176] Step S808: re-determine a new matching combination number within the range where the impedance value of the number set is less than the optimal combination number or the previous matching combination number, so as to optimize the reflection parameter.

[0177] Step S810: controlling the on and off of the corresponding matching branch according to the matching combination number and the corresponding second matching unit 142 configuration.

[0178] Step S812: Calculate the range of the combination numbers that achieve the optimal reflection parameters for a preset number of times.

[0179] Step S814: Determine whether the formal heating time (the time from step S710) is less than or equal to the first operation time. If yes, execute step S816; if not, execute step S824.

[0180] Step S816: Determine whether the range of the combination number is greater than the first correction threshold. If yes, execute step S818; if no, execute step S820.

[0181] Step S818: increasing the first extension percentage based on the current remaining heating time.

[0182] Step S820: Determine whether the range of the combination number is less than or equal to the first termination threshold. If yes, execute step S832; if not, execute step S822.

[0183] Step S822: reducing the first shortening percentage based on the current remaining heating time.

[0184] Step S824: Determine whether the range of the combination number is greater than the second correction threshold. If yes, execute step S826; if no, execute step S828.

[0185] Step S826: reducing the reduction percentage based on the current heating power, and increasing the second extension percentage based on the current remaining heating time.

[0186] Step S828: Determine whether the range of the combination number is less than or equal to the second termination threshold. If yes, execute step S832; if not, execute step S830.

[0187] Step S830: Determine whether the current remaining heating time is less than or equal to zero. If so, execute step S832; if not, return to step S802.

[0188] Step S832: Control the heating device 100 to stop working.

[0189] Fig. 9 is a detailed flow chart of a calibration control method for a heating device 100 according to an embodiment of the present invention. Fig. 9 The calibration control method for the heating device 100 of the present invention may specifically include the following steps:

[0190] Step S902: Determine whether a calibration instruction is received. If yes, execute step S904; if no, repeat step S902.

[0191] Step S904: determining the optimal on-off combination of the first matching unit 141 corresponding to one on-off combination of the calibration unit, until the optimal on-off combination of the first matching unit 141 corresponding to all on-off combinations of the calibration unit is determined.

[0192] Step S906: Determine whether the impedance value (ie, number) of the optimal on-off combination is less than a preset fault impedance threshold. If yes, execute step S918; if not, execute step S908.

[0193] Step S908: Determine whether the impedance value of the optimal on-off combination is less than or equal to a preset calibration impedance threshold. If yes, execute step S910; if not, execute step S912.

[0194] Step S910: fix the on-off combination of the current calibration unit.

[0195] Step S912: Calculate the impedance difference between each optimal on-off combination and the standard on-off combination, and compare to obtain the minimum impedance difference.

[0196] Step S914: Determine whether the minimum impedance difference is less than a preset difference threshold. If so, execute step S916; if not, execute step S918.

[0197] Step S916: fix the on-off combination of the calibration unit corresponding to the minimum impedance difference.

[0198] Step S918: prompting that the heating device 100 is faulty, and controlling the heating device 100 to stop working.

[0199] At this point, those skilled in the art should recognize that, although multiple exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications that conform to the principles of the present invention can still be directly determined or derived based on the content disclosed in the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and recognized as covering all these other variations or modifications.

Claims

1. A heating device, comprising: A cavity, used for placing objects to be processed; An electromagnetic wave generating module, configured to generate an electromagnetic wave signal for heating the object to be processed; as well as A matching module, configured to adjust the load impedance of the electromagnetic wave generating module by adjusting its own impedance; wherein the matching module comprises: A first matching unit, comprising at least one matching branch that can be independently switched on and off; and The first calibration unit includes at least one calibration branch that can be independently switched on and off, and is arranged to be connected in parallel with the first matching unit; wherein, The first calibration unit remains fixed during the process of heating the object to be processed.

2. The heating device according to claim 1, wherein: One end of the first matching unit is connected in series between the electromagnetic wave generating module and the cavity, and the other end is grounded.

3. The heating device according to claim 1, wherein: The matching module also includes: A second matching unit has one end connected in series with the electromagnetic wave generating module, and the other end connected in series between the first matching unit and the cavity.

4. The heating device according to claim 3, wherein: The second matching unit includes at least one matching branch that can be independently switched on and off, and at least one fixed branch connected in parallel with the at least one matching branch, and the impedance value of the fixed branch is fixed.

5. The heating device according to claim 1, wherein: The matching branch includes a fixed value capacitor and a switch; and The first matching unit has a plurality of matching branches, the capacitance values ​​of the fixed-value capacitors of the plurality of matching branches are different, and the capacitance value of each fixed-value capacitor is 2 times or 1 / 2 times the capacitance value of another fixed-value capacitor.

6. A control method for a heating device, wherein the heating device is a heating device according to any one of claims 1 to 5; wherein: The control method comprises: Calibration test step: sequentially determining the optimal on-off combination of the first matching unit corresponding to each on-off combination of the first calibration unit; Difference comparison step: calculating the impedance difference between each of the optimal on-off combination and the preset standard on-off combination, and comparing to obtain the minimum impedance difference; Matching calibration step: when the minimum impedance difference is less than a preset difference threshold, fixing the on-off combination of the calibration unit corresponding to the minimum impedance difference in the impedance matching before the next execution of the calibration test step.

7. The control method according to claim 6, further comprising: In the case where the impedance value of each of the optimal on-off combinations in the calibration test step is greater than a preset calibration impedance threshold, the difference comparison step is performed.

8. The control method according to claim 6, further comprising: When the impedance value of any of the optimal on-off combinations in the calibration test step is less than a preset fault impedance threshold, the calibration test step is terminated.

9. The control method according to claim 6, further comprising: When it is determined in the calibration test step that the impedance value of the first optimal on-off combination is less than or equal to a preset calibration impedance threshold and greater than or equal to a preset fault impedance threshold, the difference comparison step is skipped and the on-off combination of the calibration unit corresponding to the optimal on-off combination is fixed.

10. The control method according to claim 6, wherein the first matching unit has a plurality of matching branches, wherein: The control method further comprises: A number acquisition step: acquiring a pre-configured number set of the first matching unit, the number set including a combination number of an on-off combination of the at least one matching branch, the combination number corresponding to the impedance value of the first matching unit; wherein determining each of the optimal on-off combinations in the calibration test step includes: Benchmark determination step: determining a first test group in the number set, the first test group including a plurality of combination numbers whose impedance values ​​differ by a preset first difference value, controlling the on and off of the corresponding matching branch according to the first test group and obtaining a reflection parameter corresponding to each combination number in the first test group, and determining a first matching benchmark in the first test group according to the reflection parameter; Optimal test step: determining a second test group based on the first matching benchmark, the second test group including the first matching benchmark and a plurality of combination numbers whose impedance values ​​differ by a preset second difference value, controlling the on and off of the corresponding matching branch according to the second test group and obtaining the reflection parameter corresponding to each combination number in the second test group, and determining the second matching benchmark or the optimal combination number in the second test group according to the reflection parameter; wherein, The second difference is less than the first difference; and In the difference comparison step, the impedance difference is the difference between the optimal combination number and the standard combination number corresponding to the preset standard on-off combination.

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