Control method for a heating device and heating device

Abstract

The application provides a control method for a heating device and the heating device. The heating device comprises a cavity, an electromagnetic wave generating module and a matching module, the matching module comprises a first matching unit, and the first matching unit comprises a plurality of matching branches which can be independently turned on and off. The control method comprises: a number obtaining step, obtaining a number set of the first matching unit which is pre-configured, the number set comprising combination numbers of on-off combinations of the plurality of matching branches; a reference determining step, determining a first test group from the number set, obtaining a reflection parameter corresponding to each combination number in the first test group, and determining a first matching reference in the first test group according to the reflection parameter; and an optimal test step, determining a second test group based on the first matching reference, obtaining a reflection parameter corresponding to each combination number in the second test group, and determining a second matching reference or an optimal combination number in the second test group according to the reflection parameter, so that efficient matching can be realized. The second difference value is smaller than the first difference value.

Description

Technical Field

[0001] This invention relates to the field of food processing, and in particular to a control method and a heating device for a heating apparatus. 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 facilitate thawing, electromagnetic wave heating devices are typically used.

[0003] Using electromagnetic wave heating devices to defrost food is not only fast and efficient, but also results in minimal loss of nutrients, especially with heating devices equipped with impedance matching modules. However, to ensure adjustment accuracy and increase adaptability to different foods, impedance matching modules often have multiple matching branches, leading to excessive impedance matching time and affecting heating efficiency and effectiveness. 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 invention is to reduce the time required for impedance matching.

[0006] Another further objective of the first aspect of the present invention is to simplify the control procedure.

[0007] A second aspect of the present invention is to provide a heating device that applies the control method.

[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, an electromagnetic wave generating module for generating an electromagnetic wave signal for heating the workpiece, and a matching module for adjusting the load impedance of the electromagnetic wave generating module by adjusting its own impedance, the matching module comprising a first matching unit, the first matching unit comprising a plurality of independently switchable matching branches, wherein the control method comprises:

[0009] Numbering acquisition step: Obtain the pre-configured numbering set of the first matching unit, the numbering set including the combination number of the on / off combinations of the plurality of matching branches, the combination number corresponding to the impedance value of the first matching unit;

[0010] The reference determination step is as follows: a first test group is determined from the number set. The first test group includes multiple combination numbers with impedance values ​​that differ by a preset first difference. The on / off state of the corresponding matching branch is controlled according to the first test group, and the reflection parameter corresponding to each combination number in the first test group is obtained. The first matching reference is determined in the first test group according to the reflection parameter.

[0011] Optimal testing steps: Based on the first matching reference, a second test group is determined. The second test group includes the first matching reference with impedance values ​​differing by a preset second difference and multiple combination numbers. The on / off state of the corresponding matching branch is controlled according to the second test group, and the reflection parameters corresponding to each combination number in the second test group are obtained. Based on the reflection parameters, a second matching reference or optimal combination number is determined in the second test group.

[0012] The second difference is less than the first difference.

[0013] 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, simplifying the control program, but also, compared with the control method of the prior art that requires determining the reflection parameters of each on / off combination to compare the optimal on / off combination, it can greatly shorten the time for determining the optimal on / off combination, reduce the impact of impedance matching on the heating effect, improve heating efficiency and reduce energy consumption.

[0014] Optionally, the matching module further includes a second matching unit, which includes multiple matching branches that can be independently switched on and off; and

[0015] In the process of obtaining the reflection parameter corresponding to the combination number of the first matching unit in the benchmark determination step and the optimal test step, the on / off combinations of the second matching unit are traversed based on a combination number, and the optimal reflection parameter in the on / off combinations of the second matching unit is recorded as the reflection parameter of the combination number.

[0016] In the process of testing reflection parameters, the control method of the present invention first fixes a combination number of the test group, and then tests the reflection parameters of each on / off combination of the second matching unit corresponding to the combination number one by one. The optimal reflection parameter that can be achieved by the second matching unit for each combination number is used as the reflection parameter of the combination number. This facilitates the determination of the matching benchmark and the optimal combination number, reduces the amount of data stored at the same time, further simplifies the control program and improves the testing efficiency.

[0017] Optionally, in the benchmark determination step and the optimal test step, the better reflection parameters and the corresponding second matching unit configuration for each combination number are recorded until the optimal reflection parameters and the second matching unit configuration for that combination number are determined.

[0018] The control method of the present invention records only the better reflection parameters and the corresponding second matching unit configuration for each combination number during the test of reflection parameters. This facilitates the subsequent formal heating of the object to be processed according to the optimal configuration of the matching module, further simplifies the control program, reduces the requirements for the storage and computing performance of the supporting hardware, and thus reduces production costs.

[0019] Optionally, the following may be included after the optimal testing step:

[0020] Formal heating step: Control the on / off state of the corresponding matching branch according to the optimal combination number and the corresponding second matching unit configuration; wherein,

[0021] The heating power of the formal heating step is greater than the test power of the benchmark determination step and the optimal test step.

[0022] The control method of the present invention, after determining the optimal combination number, enables the matching module to configure the on / off state according to the optimal combination number and the corresponding second matching unit and to heat the workpiece with high power, further reducing the impact of impedance matching on the heating effect and improving the heating efficiency.

[0023] Optionally, the process may further include the following after the formal heating step:

[0024] Matching test steps: Obtain the corresponding reflection parameters based on the current configuration of the matching module;

[0025] Rematching step: When the reflection parameter is worse than the preset matching threshold or the continuous time of the matching test step is greater than the preset matching time threshold, a new matching combination number is 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. The matching combination number is the one with the best reflection parameter or the reflection parameter is better than the matching threshold.

[0026] The control method of the present invention ensures the absorption rate of electromagnetic waves by the object to be treated by re-determining the matching combination number based on the reflection parameters during the heating process and limiting the test to a range where the impedance value is less than the optimal combination number or the previous matching combination number, thereby shortening the time required for re-matching and further improving the heating efficiency.

[0027] Optionally, the second matching unit is connected in series between the electromagnetic wave generating module and the cavity, and one end of the first matching unit is connected in series between the second matching unit and the cavity, while the other end is grounded.

[0028] The matching module circuit with a specific series-parallel relationship used in this invention is not only simple and reliable, but also allows for flexible and precise adjustment of the load impedance of the electromagnetic wave generating module. Furthermore, when combined with the aforementioned optimal combination number determination method, it can obtain a more accurate optimal combination number while achieving high testing efficiency, thereby ensuring the heating effect of the workpiece throughout the entire heating process.

[0029] Optionally, the number of matching branches in the first matching unit is greater than the number of matching branches in the second matching unit.

[0030] The control method of the present invention narrows the test range by performing matching benchmark tests on matching units with more matching branches and performing traversal tests on matching units with fewer matching branches. This improves the overall testing efficiency of the optimal combination number and reduces the determination error of the optimal combination number.

[0031] Optionally, each of the matching branches includes a fixed capacitor and a switch; and

[0032] The fixed capacitors of the multiple matching branches have different capacitance values, and the capacitance value of each fixed capacitor is 2 times or 1 / 2 times the capacitance value of the other fixed capacitor.

[0033] The control method of the present invention is based on a first matching unit where the capacitance value of each fixed capacitor is twice or half the capacitance value of another fixed capacitor. This makes the difference between two adjacent numbers of the combination numbers of the first matching units sorted by impedance value the same. This not only improves the matching accuracy of the object to be processed and reduces the difference in the heating effect of different foods, but also reduces the limitation of the specific values ​​of the first and second differences preset in the design, making the control program simpler.

[0034] Optionally, the following may be included after the optimal testing step:

[0035] Initial parameter determination steps: Determine the weight of the object to be processed and / or the control parameters for heating the object to be processed based on the optimal combination number.

[0036] The control method of the present invention determines the weight and / or heating control parameters of the object to be processed based on the optimal combination number. It eliminates the need for manual input by the user or the addition of additional components to detect the initial properties of the object to be processed, thereby reducing production costs, avoiding the accumulation of errors from excessive detection data, achieving precise heating of the object to be processed, and reducing the occurrence of overheating and undercooling.

[0037] According to a second aspect of the present invention, a heating device is provided, comprising:

[0038] The cavity is used to hold the object to be processed;

[0039] An electromagnetic wave generating module is configured to generate electromagnetic wave signals for heating the object to be processed;

[0040] The matching module is configured to adjust the load impedance of the electromagnetic wave generating module by adjusting its own impedance; and

[0041] A controller configured to perform the control method as described in any of the preceding claims.

[0042] The heating device 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, simplifying the control program, but also, compared with the heating device of the prior art that requires determining the reflection parameters of each on / off combination to compare the optimal on / off combination, it can greatly shorten the time for determining the optimal on / off combination, reduce the impact of impedance matching on the heating effect, improve heating efficiency and reduce energy consumption.

[0043] 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

[0044] The following sections will describe some specific embodiments of the invention in a detailed manner 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:

[0045] Figure 1 This is a schematic structural diagram of a heating device according to an embodiment of the present invention;

[0046] Figure 2 yes Figure 1 A schematic structural diagram of the controller;

[0047] Figure 3 yes Figure 1 A schematic structural diagram of the matching module;

[0048] Figure 4 This is a schematic flowchart of a control method for initial impedance matching of a heating device according to an embodiment of the present invention;

[0049] Figure 5 This is a schematic flowchart of a control method for re-impedance matching of a heating device according to an embodiment of the present invention;

[0050] Figure 6This is a schematic flowchart of a control method for matching calibration of a heating device according to an embodiment of the present invention;

[0051] Figure 7 This is a detailed flowchart of a heating control method for a heating device according to an embodiment of the present invention;

[0052] Figure 8 yes Figure 7 The continuation part;

[0053] Figure 9 This is a detailed flowchart of a calibration control method for a heating device according to an embodiment of the present invention. Detailed Implementation

[0054] 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 for placing the object to be processed 160, an electromagnetic wave generating module 120, a radiating antenna 130, a matching module 140, and a controller 150.

[0055] The radiating antenna 130 can be disposed within the cavity 110. The electromagnetic wave generating module 120 can be configured to generate electromagnetic wave signals and electrically connected to the radiating antenna 130 to generate electromagnetic waves within the cavity 110, thereby heating the object to be processed 160 within the cavity 110.

[0056] The matching module 140 can be connected in series between the electromagnetic wave generating module 120 and the capacitor of the cavity 110 or in parallel across the capacitor of the cavity 110. It is configured to adjust the load impedance of the electromagnetic wave generating module 120 by adjusting its own impedance, so as to achieve load matching and improve heating efficiency.

[0057] Figure 2 yes Figure 1 A schematic structural diagram of the controller 150. See also... 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, which, when executed by the processing unit 151, is used to implement the control method of the embodiments of the present invention.

[0058] Figure 3 yes Figure 1 A schematic structural diagram of the matching module 140. See also... Figure 1 The matching module 140 may include a first matching unit 141.

[0059] The first matching unit 141 may include multiple matching branches that can be independently switched on and off, so as to form different impedance values ​​through different combinations of switching on and off.

[0060] Each matching branch of the first matching unit 141 may include a fixed capacitor C. X And a switch K X .

[0061] exist Figure 3 In the illustrated embodiment, the first matching unit 141 may include a fixed capacitor C. X1 ~C X5 and respectively on / off C X1 ~C X5 switch K X1 ~K X5 Five matching branches were formed.

[0062] In some embodiments, the processing unit 151 may be configured to acquire a set of numbers of a pre-configured first matching unit 141, determine a first matching reference in the set of numbers, and further determine a second matching reference or optimal combination number based on the first matching reference, for heating the object to be processed 160.

[0063] The number set may include combination numbers of multiple matching branch on / off combinations, and the combination number corresponds to the impedance value of the first matching unit 141, so that the impedance value can be calculated through the combination number itself.

[0064] The processing unit 151 can be specifically configured to determine a first test group from the set of numbers, control the on / off state of the corresponding matching branch according to the first test group, obtain the reflection parameters corresponding to each combination number in the first test group, and determine a first matching reference in the first test group based on the reflection parameters, so as to shorten the time used to determine the optimal on / off combination. The impedance values ​​of multiple combination numbers in the first test group can differ by a preset first difference value.

[0065] For example, the reflection parameter can be the return loss S11. The minimum value of the return loss S11 indicates the optimal on / off combination; the maximum value of the return loss S11 indicates the worst on / off combination.

[0066] The processing unit 151 can be specifically configured to determine a second test group based on a first matching reference, control the on / off state of the corresponding matching branch according to the second test group and obtain the reflection parameters corresponding to each combination number in the second test group, and determine a second matching reference or optimal combination number in the second test group based on the reflection parameters. The impedance values ​​of multiple combination numbers in the second test group and the first matching reference can differ by a preset second difference value, and the second difference value is less than the first difference value.

[0067] The testing range for the second test group can be the range drawn with the first matching benchmark as the center and the first difference as the radius.

[0068] Understandably, the number of on / off combinations of the first matching unit 141 can be used to select whether it is necessary to determine a second matching benchmark or even a third matching benchmark to further narrow down the test range and finally obtain the optimal combination number.

[0069] The fixed capacitor C of the first matching unit 141 X1 ~C X5 The capacitance values ​​can be different. The capacitance value of each fixed capacitor is 2 times or 1 / 2 times the capacitance value of another fixed 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 on the specific values ​​of the first difference and the second difference preset in the design.

[0070] 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 are indicated, where “√” indicates on and “×” indicates off.

[0071] Table 1

[0072] √ × × <![CDATA[C U ]]> 1 × √ × <![CDATA[2C U ]]> 2 √ √ × <![CDATA[3C U ]]> 3 × × √ <![CDATA[4C U ]]> 4 √ × √ <![CDATA[5C U ]]> 5 × √ √ <![CDATA[6C U ]]> 6 √ √ √ <![CDATA[7C U ]]> 7

[0073] For single fixed capacitors that carry a large current when in the conducting state, they can be replaced by multiple fixed capacitors with smaller capacitance values ​​connected in parallel and a linkage switch that simultaneously turns these multiple fixed capacitors on or off. For example, C X5 and K X5 .

[0074] In some further embodiments, the matching module 140 may also include a second matching unit 142.

[0075] The second matching unit 142 may include multiple matching branches that can be independently switched on and off, so as to form different impedance values ​​through different combinations of switching on and off.

[0076] Each matching branch of the second matching unit 142 may include a fixed capacitor C. Y And a switch K Y .

[0077] exist Figure 3 In the illustrated embodiment, the second matching unit 142 may include a fixed capacitor C. Y1 ~C Y3 and respectively on / off C Y1 ~C Y3 switch K Y1 ~K Y3The three matching branches formed.

[0078] The processing unit 151 can be configured to, when acquiring the reflection parameters corresponding to the combination number of the first matching unit 141, traverse the on / off combinations of the second matching unit 142 based on a combination number, and record the optimal reflection parameter among the on / off combinations of the second matching unit 142 as the reflection parameter of that 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 that 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.

[0079] In some further embodiments, the processing unit 151 may be configured to record the optimal reflection parameters and corresponding second matching unit 142 configuration for each combination number when traversing the on / off combinations of the second matching unit 142, until the optimal reflection parameters and second matching unit 142 configuration for that combination number are determined. That is, only the optimal reflection parameters and corresponding second matching unit 142 configuration for each combination number are recorded, which facilitates subsequent formal heating of the workpiece 160 according to the optimal configuration of the matching module 140, further simplifying the control procedure.

[0080] In some further embodiments, the processing unit 151 may be configured to, after confirming the optimal combination number, control the on / off state of the corresponding matching branch according to the optimal combination number and the corresponding second matching unit 142 configuration, and start efficient heating of the object to be processed 160.

[0081] 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 impact of impedance matching on the heating effect.

[0082] 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.

[0083] The first matching unit 141 can be connected in series at one end 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.

[0084] The second matching unit 142 may further include at least one fixed branch connected in parallel with the matching branch. The impedance value of the fixed branch remains constant, for example, C. Y To improve the security of the matching module 140.

[0085] 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 overall testing efficiency of the optimal combination number and reduce the determination error of the optimal combination number.

[0086] In some further embodiments, the processing unit 151 may be configured to determine whether a preset tuning condition is met during the heating process, and if 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 condition, thereby ensuring the heating efficiency of the object to be processed 160.

[0087] The tuning conditions may include a reflection parameter being worse than a preset matching threshold, or the continuous time for which the tuning conditions are met being greater than a preset matching time threshold. That is, when either the "reflection parameter being worse than a preset matching threshold" or "the continuous time for which the tuning conditions are met being greater than a preset matching time threshold" is reached, the control matching module 140 adjusts to achieve re-matching.

[0088] Matching criteria may include optimal reflection parameters. Alternatively, matching criteria may include reflection parameters that are better than a matching threshold.

[0089] The tuning conditions for the entire heating process, starting from the receipt of the heating command, may also include receiving the heating command, and the matching conditions may also include the initial adjustment of the reflection parameters of the matching module 140 to be optimal.

[0090] The processing unit 151 can be configured to repeatedly acquire the corresponding reflection parameters based on the current configuration of the matching module 140 during the heating process until the tuning conditions are met.

[0091] In some further embodiments, the processing unit 151 may be configured to, during the rematching process, redetermine a new matching combination number within a 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 ensure the absorption rate of electromagnetic waves by the object to be processed 160 and shorten the time required for rematching.

[0092] In some embodiments, the processing unit 151 may 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 based on the optimal combination number after determining the optimal combination number, so as to reduce production costs, avoid the superposition of errors in too many detection data, and achieve accurate heating of the object to be processed 160.

[0093] In some embodiments, the processing unit 151 may be configured to adjust the control parameters of the heated workpiece 160 according to the impedance range of the first matching unit 141 that meets the matching conditions a preset number of times, thereby mitigating or resolving the problem of uneven temperature or overheating / undercooling of the workpiece 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.

[0094] For example, if the preset number of times is four, the first impedance range should be the range between the initially determined optimal combination number and the matching combination number of the first three rematches.

[0095] In some further embodiments, the processing unit 151 may be configured to determine a reference threshold for correcting control parameters based on the optimal combination number, so as to know the difference between the current state and the design state of the object to be processed 160.

[0096] In some further embodiments, the control parameters may include the remaining heating time. The reference thresholds may include a first correction threshold and a first termination threshold.

[0097] The processing unit 151 can be configured to increase a preset first extension percentage based on the current remaining heating time when the impedance difference is greater than a first correction threshold, so as to avoid the object to be processed 160 from becoming too cold.

[0098] The processing unit 151 can be configured to reduce a preset first shortening percentage based on the current remaining heating time when the impedance difference is less than or equal to a first correction threshold and greater than a first termination threshold, so as to avoid overheating of the workpiece 160.

[0099] The processing unit 151 can be configured to control the electromagnetic wave generating module 120 to stop working or complete the 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.

[0100] In some further embodiments, the control parameters may include heating power. The reference threshold may include a second correction threshold and a second termination threshold.

[0101] The processing unit 151 can be configured to reduce the temperature uniformity of the object to be processed 160 by a preset reduction percentage based on the current heating power when the impedance difference is greater than the second correction threshold.

[0102] The processing unit 151 can be configured to maintain the current heating power unchanged when the impedance difference is less than or equal to the second correction threshold and greater than the second termination threshold.

[0103] The processing unit 151 can 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.

[0104] The processing unit 151 may be further configured to reduce the heating power while increasing the preset second extension percentage based on the current remaining heating time, so as to avoid the object to be processed 160 being not heated sufficiently.

[0105] In some further embodiments, the processing unit 151 may be configured to first adjust the remaining heating time according to a first correction threshold and a first termination threshold within a first operating time, and then adjust the heating power for a second operating time according to a second correction threshold and a second termination threshold, until heating is completed, so as to simplify the control program while ensuring the heating effect. The first operating time may be positively correlated with the initially determined remaining heating time.

[0106] In some embodiments, the matching module 140 may further include a first calibration unit 143 connected in parallel with a matching unit.

[0107] 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 of the object to be processed 160 and is only used to adjust the adjustable range of the matching unit as a whole. It does not directly participate in impedance matching by adjusting its own impedance, that is, there is no need to make adaptation improvements to the control methods related to impedance matching, thus ensuring the heating effect of the heating device 100 for long-term use.

[0108] 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.

[0109] Each calibration branch of the first calibration unit 143 may include a fixed capacitor C. Z And a switch K Z .

[0110] exist Figure 3 In the illustrated embodiment, the first calibration unit 143 may include a fixed capacitor C. Z1 ~C Z2 and respectively on / off C Z1 ~C Z2 switch K Z1 ~K Z2 The two calibration branches are formed.

[0111] The second matching unit 142 and the first calibration unit 143 can also be numbered as the first matching unit 141.

[0112] In some further embodiments, the processing unit 151 may be configured to sequentially determine 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. If 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 so that the heating device 100 is close to the ideal state of the design, thereby achieving the best heating effect.

[0113] The impedance difference can be the difference between the optimal combination number and the standard combination number corresponding to the preset standard on / off combination.

[0114] In some further embodiments, the processing unit 151 may be configured to terminate the calibration when the impedance value of any optimal on / off combination is less than a preset fault impedance threshold during the determination of the optimal on / off combination, thereby reducing the user's waiting time and unnecessary energy consumption.

[0115] In some further embodiments, the processing unit 151 may be configured to, during the process of determining the optimal on / off combination, if 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, directly fix the on / off combination of the calibration unit corresponding to the optimal on / off combination, thereby simplifying the control program while ensuring the calibration effect.

[0116] 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 during the process of determining the optimal on / off combination.

[0117] In 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 same method as the initial impedance matching can be used to determine the optimal on / off combination by first narrowing the test range by determining the matching reference, so as to improve calibration efficiency.

[0118] The first calibration unit 143 may also include a fixed branch connected in parallel with the calibration branch. The impedance value of the fixed branch remains constant, for example, C. Z To improve the security of the matching module 140.

[0119] It should be noted that the calibration unit of the present invention is also applicable to a matching unit with only one matching branch; alternatively, a calibration unit may be provided for each matching unit.

[0120] In some embodiments, the matching module 140 may further 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, so as 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.

[0121] Figure 4 This is a schematic flowchart of a control method for initial impedance matching of a heating device 100 according to an embodiment of the present invention. See also Figure 4 The control method for initial impedance matching executed by the controller 150 of any of the above embodiments of the present invention may include the following steps:

[0122] Step S402 (Number Acquisition): Acquire the number set of the pre-configured first matching unit 141. The number set includes the combination number of the on / off combinations of multiple matching branches. The combination number corresponds to the impedance value of the first matching unit 141.

[0123] Step S404 (Reference Determination): Determine the first test group from the number set. The first test group includes multiple combination numbers with impedance values ​​that differ by a preset first difference. Control the on / off state 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. Determine the first matching reference in the first test group based on the reflection parameter.

[0124] Step S406 (Optimal Test): Determine the second test group based on the first matching reference. The second test group includes the first matching reference with a preset second difference in impedance values ​​and multiple combination numbers. Control the on / off state of the corresponding matching branch according to the second test group and obtain the reflection parameters corresponding to each combination number in the second test group. Determine the second matching reference or optimal combination number in the second test group based on the reflection parameters. The second difference is less than the first difference.

[0125] The control method of the present invention assigns numbers to the on / off combinations of the first matching unit 141 and obtains the optimal combination number 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, simplifying the control program, but also, compared with the control method in the prior art that requires determining the reflection parameters of each on / off combination to compare the optimal on / off combination, it can greatly shorten the time for determining the optimal on / off combination, reduce the impact of impedance matching on the heating effect, improve heating efficiency and reduce energy consumption.

[0126] For example, the reflection parameter can be the return loss S11. The minimum value of the return loss S11 indicates the optimal on / off combination; the maximum value of the return loss S11 indicates the worst on / off combination.

[0127] In an embodiment where the matching module 140 also includes a second matching unit 142, during the process of obtaining the reflection parameters 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 among the on / off combinations of the second matching unit 142 is recorded as the reflection parameter of that combination number. That is, a combination number of the test group is fixed first, and then the reflection parameters of each on / off combination of the second matching unit 142 corresponding to that combination number are 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.

[0128] In some further embodiments, during the baseline determination step and the optimal testing step, the better reflection parameters and the corresponding second matching unit 142 configuration for each combination number can be recorded until the optimal reflection parameters and the second matching unit 142 configuration for that combination number are determined. That is, only the optimal reflection parameters and the corresponding second matching unit 142 configuration for each combination number are recorded, which facilitates subsequent formal heating of the workpiece 160 according to the optimal configuration of the matching module 140, further simplifying the control procedure.

[0129] In some embodiments, the control method of the present invention may further include, after the optimal testing step:

[0130] Formal heating step: The on / off state of the corresponding matching branch is controlled according to the optimal combination number and the corresponding second matching unit 142 configuration. The heating power in the formal heating step is greater than the test power in the benchmark determination step and the optimal test step to reduce the impact of impedance matching on the heating effect and improve heating efficiency.

[0131] In some embodiments, the control method of the present invention further includes, after the formal heating step:

[0132] Matching test steps: Obtain the corresponding reflection parameters based on the current configuration of the matching module 140;

[0133] Re-matching 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 to be processed 160.

[0134] The tuning conditions for the re-matching step may include the reflection parameter being worse than a preset matching threshold, or the continuous time for which the tuning conditions are met being greater than a preset matching time threshold. That is, when either the "reflection parameter being worse than a preset matching threshold" or the "continuous time for which the tuning conditions are met being greater than a preset matching time threshold" is met, the control matching module 140 adjusts to achieve re-matching.

[0135] The matching criteria for the rematching step may include optimal reflection parameters. Alternatively, the matching criteria for the rematching step may include reflection parameters that are better than a matching threshold.

[0136] The aforementioned benchmark determination step and optimal test step, together with the re-matching step, can be collectively referred to as the impedance matching step. The tuning conditions for this impedance matching step may also include receiving a heating command, and the matching conditions may also include the initial adjustment of the reflection parameters of the matching module 140 to be optimal.

[0137] In some further embodiments, during the rematching step, a new matching combination number can be determined within a range where the impedance value of the number set is less than the optimal combination number or the previous matching combination number, in order to ensure the absorption rate of electromagnetic waves by the object to be processed 160 and shorten the time required for rematching.

[0138] In some embodiments, the control method of the present invention further includes, after the optimal testing step:

[0139] Preliminary parameter determination steps: Determine the weight of the object to be processed 160 and / or the control parameters for heating the object to be processed 160 based on the optimal combination number, so as to reduce production costs, avoid the accumulation of errors in too many detection data, and achieve precise heating of the object to be processed 160.

[0140] Figure 5 This is a schematic flowchart of a control method for re-impedance matching of a heating device 100 according to an embodiment of the present invention. See also Figure 5 The control method for re-impedance matching executed by the controller 150 of any of the above embodiments of the present invention may include the following steps:

[0141] Step S502 (Impedance Matching): 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.

[0142] Step S504 (Parameter Correction): Adjust the control parameters of the heated workpiece 160 according to the impedance range of the first matching unit 141 that meets the matching conditions according to a preset number of times. The impedance range can be the range of the combination number.

[0143] The control method of the present invention adjusts the control parameters of the heated object 160 according to the impedance difference of the matching unit with one end grounded within a preset number of times to meet the matching conditions, corrects the parameters initially determined for heating, and reduces or solves the problem of uneven temperature or overheating of the heated object 160 caused by factors such as insufficient user experience or system errors (such as the accuracy of the detection element or insufficient method for determining the initial parameters). It is compatible with foods with various attribute parameters and can avoid unwanted energy waste.

[0144] In some embodiments, the control method of the present invention further determines a reference threshold for correcting the control parameters based on the optimal combination number in the parameter initialization step, so as to know the difference between the current state and the design state of the object to be processed 160.

[0145] In some further embodiments, the control parameters include the remaining heating time, and the reference thresholds include a first correction threshold and a first termination threshold. The parameter correction step may include:

[0146] The first correction step is as follows: if the impedance difference is greater than the first correction threshold, increase the preset first extension percentage based on the current remaining heating time to prevent the object to be processed 160 from becoming too cold; if the impedance difference is less than or equal to the first correction threshold but greater than the first termination threshold, decrease the preset first shortening percentage based on the current remaining heating time to prevent the object to be processed 160 from becoming too hot; if the impedance difference is less than or equal to the first termination threshold, control the electromagnetic wave generating module 120 to stop working or complete the heating according to the current remaining heating time to avoid energy waste or poor heating effect.

[0147] In some further embodiments, the control parameters include heating power, and the reference thresholds include a second correction threshold and a second termination threshold. The parameter correction step may include:

[0148] Power correction steps: When the impedance 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 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 difference is less than or equal to the second termination threshold, control the electromagnetic wave generation module 120 to stop working to prevent the object to be processed 160 from being overheated.

[0149] In some further embodiments, the parameter correction step may also include:

[0150] The second time correction step: while reducing the preset reduction percentage based on the current heating power, the preset second extension percentage is increased based on the current remaining heating time to avoid the object to be processed 160 being insufficiently heated.

[0151] In some further embodiments, the first time correction step and the power correction step can be run for a first running time and a second running time, respectively. The first running time is positively correlated with the remaining heating time determined in the parameter initialization step.

[0152] After the first correction step is completed, the power correction step is run again to simplify the control program while ensuring heating effect.

[0153] Figure 6This is a schematic flowchart of a control method for matching calibration of a heating device 100 according to an embodiment of the present invention. See also Figure 6 The control method for matching calibration executed by the controller 150 of any of the above embodiments of the present invention may include the following steps:

[0154] Step S602 (calibration test): Sequentially determine the optimal on / off combination of the first matching unit 141 corresponding to each on / off combination of the first calibration unit 143;

[0155] Step S604 (Difference Comparison): Calculate the impedance difference between each optimal on / off combination and the preset standard on / off combination, and compare the minimum impedance difference.

[0156] Step S606 (Matching Calibration): If the minimum impedance difference is less than the preset difference threshold, fix the on / off combination of the calibration unit corresponding to the minimum impedance difference in the impedance matching before the next calibration test step.

[0157] The control method of the present invention selects a fixed on / off combination of a 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.

[0158] 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. That is, it makes an initial judgment on 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, thus avoiding excessive repetition and complexity in the control program.

[0159] 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 in the calibration test step is less than a preset fault impedance threshold, thereby reducing user waiting time and unnecessary energy consumption.

[0160] In some further embodiments, the control method of the present invention skips the difference comparison step and fixes the on / off combination of the calibration unit corresponding to the first optimal on / off combination when 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 during the calibration test step. This simplifies the control program while ensuring the calibration effect.

[0161] In some further embodiments, the control method of the present invention may specifically employ the same or similar steps as the benchmark determination step and the optimal test step in determining each optimal on / off combination during the calibration test step, thereby improving calibration efficiency.

[0162] Figure 7 This is a detailed flowchart of a heating control method for a heating device 100 according to an embodiment of the present invention; Figure 8 yes Figure 7 The following part (in the attached diagram, "Y" indicates "yes"; "N" indicates "no"). See also Figure 7 and Figure 8 The heating control method for the heating device 100 of the present invention may specifically include the following steps:

[0163] Step S702: Determine whether a heating command has been received. If yes, proceed to step S704; otherwise, repeat step S702.

[0164] Step S704: Obtain the number set of the pre-configured first matching unit 141. The number set includes the combination number of the on / off combination of multiple matching branches. The combination number corresponds to the impedance value of the first matching unit 141.

[0165] Step S706: Determine the first test group from the number set. The first test group includes multiple combination numbers with impedance values ​​that differ by a preset first difference. Control the on / off state 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. Determine the first matching reference in the first test group based on the reflection parameter.

[0166] Step S708: Determine the second test group based on the first matching reference. The second test group includes the first matching reference with a preset second difference in impedance values ​​and multiple combination numbers. Control the on / off state of the corresponding matching branch according to the second test group and obtain the reflection parameters corresponding to each combination number in the second test group. Determine the second matching reference or the optimal combination number in the second test group based on the reflection parameters.

[0167] Step S710: Determine the remaining heating time, correction threshold and termination threshold according to the optimal combination number, and control the on / off state of the corresponding matching branch according to the optimal combination number and the corresponding second matching unit 142 configuration.

[0168] Step S802: Obtain the corresponding reflection parameters based on the current configuration of the matching module 140.

[0169] Step S804: Determine whether the reflection parameter is greater than the preset matching threshold. If yes, proceed to step S808; if no, proceed to step S806.

[0170] Step S806: Determine whether the continuous time of the current configuration used by the matching module 140 is greater than a preset time threshold. If yes, proceed to step S808; otherwise, return to step S802.

[0171] Step S808: Within the range where the impedance value of the numbered set is less than the optimal combination number or the previous matching combination number, a new matching combination number is determined to optimize the reflection parameters.

[0172] Step S810: Configure the on / off state of the corresponding matching branch according to the matching combination number and the corresponding second matching unit 142.

[0173] Step S812: Calculate the range of the combination number that achieves the optimal reflection parameters for the preset number of times.

[0174] Step S814: Determine whether the formal heating time (time since step S710) is less than or equal to the first running time. If yes, proceed to step S816; otherwise, proceed to step S824.

[0175] Step S816: Determine whether the range of the combination numbers is greater than the first correction threshold. If yes, proceed to step S818; if no, proceed to step S820.

[0176] Step S818: Add a first extension percentage to the current remaining heating time.

[0177] Step S820: Determine whether the range of the combination numbers is less than or equal to the first termination threshold. If yes, proceed to step S832; otherwise, proceed to step S822.

[0178] Step S822: Reduce the first shortening percentage based on the current remaining heating time.

[0179] Step S824: Determine whether the range of the combination numbers is greater than the second correction threshold. If yes, proceed to step S826; if no, proceed to step S828.

[0180] Step S826: Reduce the reduction percentage based on the current heating power and increase the second extension percentage based on the current remaining heating time.

[0181] Step S828: Determine whether the range of the combination numbers is less than or equal to the second termination threshold. If yes, proceed to step S832; if no, proceed to step S830.

[0182] Step S830: Determine if the current remaining heating time is less than or equal to zero. If yes, proceed to step S832; otherwise, return to step S802.

[0183] Step S832: Control the heating device 100 to stop working.

[0184] Figure 9 This is a detailed flowchart of a calibration control method for a heating device 100 according to an embodiment of the present invention. See also Figure 9The calibration control method for the heating device 100 of the present invention may specifically include the following steps:

[0185] Step S902: Determine whether a calibration command has been received. If yes, proceed to step S904; otherwise, repeat step S902.

[0186] Step S904: Determine 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.

[0187] Step S906: Determine whether the impedance value (i.e., number) of the optimal on / off combination is less than the preset fault impedance threshold. If yes, proceed to step S918; if no, proceed to step S908.

[0188] Step S908: Determine whether the impedance value of the optimal on / off combination is less than or equal to the preset calibration impedance threshold. If yes, proceed to step S910; if no, proceed to step S912.

[0189] Step S910: Fix the on / off combination of the current calibration unit.

[0190] Step S912: Calculate the impedance difference between each optimal on / off combination and the standard on / off combination, and compare the minimum impedance difference.

[0191] Step S914: Determine whether the minimum impedance difference is less than a preset difference threshold. If yes, proceed to step S916; if no, proceed to step S918.

[0192] Step S916: Fix the on / off combination of the calibration unit corresponding to the minimum impedance difference.

[0193] Step S918: Indicate a malfunction in heating device 100 and control heating device 100 to stop working.

[0194] 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, an electromagnetic wave generating module for generating an electromagnetic wave signal for heating the workpiece, and a matching module for adjusting the load impedance of the electromagnetic wave generating module by adjusting its own impedance, the matching module comprising a first matching unit, the first matching unit comprising multiple independently switchable matching branches, wherein, The control method includes: Numbering acquisition step: Obtain the pre-configured numbering set of the first matching unit, the numbering set including the combination number of the on / off combinations of the plurality of matching branches, the combination number corresponding to the impedance value of the first matching unit; The reference determination step is as follows: a first test group is determined from the number set. The first test group includes multiple combination numbers with impedance values ​​that differ by a preset first difference. The on / off state of the corresponding matching branch is controlled according to the first test group, and the reflection parameter corresponding to each combination number in the first test group is obtained. The first matching reference is determined in the first test group according to the reflection parameter. Optimal testing steps: Based on the first matching reference, a second test group is determined. The second test group includes the first matching reference with impedance values ​​differing by a preset second difference and multiple combination numbers. The on / off state of the corresponding matching branch is controlled according to the second test group, and the reflection parameters corresponding to each combination number in the second test group are obtained. Based on the reflection parameters, a second matching reference or optimal combination number is determined in the second test group. The second difference is less than the first difference.

2. The control method according to claim 1, wherein, The matching module further includes a second matching unit, which includes multiple matching branches that can be independently switched on and off; and In the process of obtaining the reflection parameter corresponding to the combination number of the first matching unit in the benchmark determination step and the optimal test step, the on / off combinations of the second matching unit are traversed based on a combination number, and the optimal reflection parameter in the on / off combinations of the second matching unit is recorded as the reflection parameter of the combination number.

3. The control method according to claim 2, wherein, In the benchmark determination step and the optimal test step, the better reflection parameters and the corresponding second matching unit configuration for each combination number are recorded until the optimal reflection parameters and the second matching unit configuration for that combination number are determined.

4. The control method according to claim 3, wherein, Following the optimal testing steps, the following is also included: Formal heating step: Control the on / off state of the corresponding matching branch according to the optimal combination number and the corresponding second matching unit configuration; wherein, The heating power of the formal heating step is greater than the test power of the benchmark determination step and the optimal test step.

5. The control method according to claim 4, wherein, Following the formal heating step, the following is also included: Matching test steps: Obtain the corresponding reflection parameters based on the current configuration of the matching module; Re-matching step: When the tuning conditions are met, new matching combination numbers that satisfy the matching conditions are determined within the range where the impedance value of the number set is less than the impedance value corresponding to the optimal combination number or the previous matching combination number; wherein, The tuning conditions include the reflection parameter being worse than a preset matching threshold, or the continuous time for running the matching test steps being greater than a preset matching time threshold. The matching conditions include optimal reflection parameters or reflection parameters that are better than the matching threshold.

6. The control method according to claim 2, wherein, The second matching unit is connected in series between the electromagnetic wave generating module and the cavity, and one end of the first matching unit is connected in series between the second matching unit and the cavity, while the other end is grounded.

7. The control method according to claim 2, wherein, The number of matching branches in the first matching unit is greater than the number of matching branches in the second matching unit.

8. The control method according to claim 1, wherein, Each of the matching branches includes a fixed capacitor and a switch; and The fixed capacitors of the multiple matching branches have different capacitance values, and the capacitance value of each fixed capacitor is 2 times or 1 / 2 times the capacitance value of the other fixed capacitor, so that the impedance values ​​corresponding to all on / off combinations of the first matching unit are sorted in order of magnitude to form an arithmetic sequence.

9. The control method according to claim 1, wherein, Following the optimal testing steps, the following is also included: Initial parameter determination steps: Determine the weight of the object to be processed and / or the control parameters for heating the object to be processed based on the optimal combination number.

10. A heating device, comprising: A cavity, used to hold the object to be processed; An electromagnetic wave generating module is configured to generate electromagnetic wave signals for heating the object to be processed; The matching module is configured to adjust the load impedance of the electromagnetic wave generating module by adjusting its own impedance; as well as A controller configured to perform the control method according to any one of claims 1-9.

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