Control method for a heating device and heating device

Abstract

The present invention provides a control method for a heating device and a heating device. The heating device includes an electromagnetic wave generating module that generates an electromagnetic wave signal for heating a workpiece, and a matching module that adjusts the load impedance of the electromagnetic wave generating module by adjusting its own impedance. The control method includes the steps of controlling the electromagnetic wave generating module to generate an electromagnetic wave signal with a predetermined heating power, determining the load matching level of the electromagnetic wave generating module, and adjusting the impedance of the matching module according to the load matching level. If the determined load matching levels within a predetermined adjustment time are all below a first matching threshold, the operation of the electromagnetic wave generating module is controlled to stop. This prevents the workpiece, which contains a large amount of components with low electromagnetic wave absorption capacity, from being continuously heated after its water content changes from ice to liquid, and also prevents the workpiece from being overheated, thereby ensuring the quality of the workpiece, reducing undesirable energy waste, and extending the service life of the electromagnetic wave generating module.

Description

Technical Field

[0001] The present invention relates to the field of food processing, and particularly to a control method for an electromagnetic wave heating device and a heating device.

Background Art

[0002] The quality of food is maintained during freezing, but frozen food needs to be thawed before processing or consumption. To facilitate food thawing by users, food is usually thawed by an electromagnetic wave heating device.

[0003] Food thawing by an electromagnetic wave heating device is rapid and efficient, with little loss of food nutrients. However, due to differences in the composition components of different types of food itself, there are differences in the ability to absorb electromagnetic waves. Furthermore, depending on the material of the container in which the food is placed, there are also differences in the ability of the entire food and container to absorb electromagnetic waves, and the electromagnetic wave generation module may not be able to stop operating accurately and appropriately within the time, resulting in the food being overheated or the energy of the system being wasted. From the above, it is necessary in design to provide a control method and a heating device for an electromagnetic wave heating device that can end thawing more accurately and appropriately.

Summary of the Invention

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

[0005] A further object of the first aspect of the present invention is to save energy.

[0006] A further object of the first aspect of the present invention is to extend the service life of the electromagnetic wave generation module.

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

[0008] According to a first aspect of the present invention, there is provided a control method for a heating device including an electromagnetic wave generation module that generates an electromagnetic wave signal for heating an object to be processed, and a matching module that adjusts the load impedance of the electromagnetic wave generation module by adjusting its own impedance. The control method includes: Controlling the electromagnetic wave generation module to generate an electromagnetic wave signal with a preset heating power; Determining a load matching degree of the electromagnetic wave generation module, and adjusting the impedance of the matching module according to the load matching degree. The control method further includes: When the load matching degrees determined within a preset adjustment time are all below a first matching threshold, controlling to stop the operation of the electromagnetic wave generation module.

[0009] Optionally, the control method further includes: Determining the preset adjustment time according to the weight of the object to be processed.

[0010] Optionally, the step of determining the preset adjustment time according to the weight of the object to be processed includes: Adjusting the preset adjustment time according to a preset weight-time correspondence relationship according to the weight, The preset adjustment times corresponding to different weights are recorded in the weight-time correspondence relationship, and the preset adjustment time has a positive correlation with the weight.

[0011] Optionally, the control method further includes: When the load matching degree is below a second matching threshold, controlling to stop the operation of the electromagnetic wave generation module. The second matching threshold is smaller than the first matching threshold.

[0012] Optionally, the control method further includes: Determining a change rate of the dielectric constant of the object to be processed. When the change rate is less than or equal to a change rate threshold value, further including a step of controlling to stop the operation of the electromagnetic wave generation module.

[0013] Optionally, the control method further includes a step of determining the change rate threshold value according to the weight of the object to be processed.

[0014] Optionally, the step of determining the change rate threshold value according to the weight of the object to be processed includes matching the change rate threshold value according to a preset weight change rate correspondence relationship corresponding to the weight, wherein different change rate threshold values corresponding to different weights are recorded in the weight change rate correspondence relationship, and the change rate threshold value has a negative correlation with the weight.

[0015] Optionally, before the step of controlling the electromagnetic wave generation module to generate an electromagnetic wave signal with a preset heating power, a step of controlling the electromagnetic wave generation module to generate an electromagnetic wave signal with a preset initial power, a step of adjusting the impedance of the matching module and determining the impedance value of the matching module at which the load matching degree of the electromagnetic wave generation module is maximized, further including a step of determining the weight according to the impedance value, When all of the plurality of impedance values of the matching module result in the maximum load matching degree of the electromagnetic wave generation module, in the step of determining the weight according to the impedance value, the weight is determined based on the maximum impedance value.

[0016] Optionally, the control method includes a step of determining the load matching degree of the electromagnetic wave generation module at preset time intervals, and / or when the load matching degree is less than or equal to a first matching threshold value, further including a step of adjusting the impedance of the matching module according to the load matching degree.

[0017] According to a second aspect of the present invention, a cavity capacitor for placing an object to be processed, an electromagnetic wave generation module configured to generate an electromagnetic wave signal for heating the object to be processed in the cavity capacitor, a matching module configured to adjust the load impedance of the electromagnetic wave generation module by adjusting its own impedance, and a controller configured to execute the control method according to any one of the above items, and a heating device is provided.

[0018] The present invention determines the load matching degree after impedance adjustment, and when the load matching degrees continuously determined within a preset adjustment time are all below a preset first matching degree, the operation of the electromagnetic wave generation module is stopped, and the object to be processed containing many components with low electromagnetic wave absorption ability is prevented from being continuously heated after its moisture changes from ice to liquid, further preventing the object to be processed from being overheated, ensuring the quality of the object to be processed, reducing waste of undesirable energy, and extending the service life of the electromagnetic wave generation module.

[0019] Furthermore, the present invention can stop the object to be processed in a state desired by the user by judging whether the heating of the object to be processed is completed according to the change rate of the dielectric constant of the object to be processed, compared with the method of judging whether the heating is completed according to the temperature and time. For example, since the change rate threshold can be set so that the heated food stops at -4 to -2°C, the object to be processed can be easily cut and splashing of blood from meat objects to be processed can be avoided.

[0020] Furthermore, in the present invention, the electromagnetic wave generation module stops operating when the load matching degree is below a second matching threshold, preventing the load matching degree from becoming too low due to objects to be processed that are too heavy, too large, or too small, and also preventing a large amount of electromagnetic waves from being reflected back to the electromagnetic wave generation module, burning out the electromagnetic wave generation module, or causing a safety risk.

[0021] By explaining the specific embodiments of the present invention in detail in conjunction with the following attached drawings, those skilled in the art can better understand the above and other objects, advantages, and features of the present invention.

Brief Description of the Drawings

[0022] Hereinafter, some specific embodiments of the present invention will be described in detail by way of illustration and not limitation with reference to the attached drawings. In the attached drawings, the same reference numerals represent the same or similar members or parts. Those skilled in the art will understand that these drawings are not necessarily drawn to scale.

[0023]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0024] FIG. 1 is a schematic structural diagram showing a heating device 100 according to an embodiment of the present invention. Referring to FIG. 1, the heating device 100 includes a cavity capacitor 110, an electromagnetic wave generation module 120, a matching module 130, and a controller 140.

[0025] Specifically, the cavity capacitor 110 includes a cavity for placing the object to be processed 150 and a radiation electrode plate provided in the cavity. In some embodiments, a receiving electrode plate for forming a capacitor together with the radiation electrode plate is provided in the cavity. In some other embodiments, the cavity is made of metal and forms a capacitor together with the radiation electrode plate as the receiving electrode plate.

[0026] The electromagnetic wave generation module 120 is configured to generate an electromagnetic wave signal, be electrically connected to the radiation electrode plate of the cavity capacitor 110, generate an electromagnetic wave in the cavity capacitor 110, and further heat the object to be processed 150 in the cavity capacitor 110.

[0027] The matching module 130 is configured to be connected in series between the electromagnetic wave generation module 120 and the cavity capacitor 110 or connected in parallel across both ends of the cavity capacitor 110, and adjust the load impedance of the electromagnetic wave generation module 120 by adjusting its own impedance, so as to achieve load matching and improve heating efficiency.

[0028] FIG. 2 is a schematic structural diagram showing the controller 140 in FIG. 1. Referring to FIG. 2, the controller 140 includes a processing unit 141 and a storage unit 142. Here, a computer program 143 is stored in the storage unit 142, and when the computer program 143 is executed by the processing unit 141, the control method of the embodiment of the present invention is realized.

[0029] The processing unit 141 is configured to control the electromagnetic wave generation module 120 to generate an electromagnetic wave signal with a preset heating power, then determine the load matching degree of the electromagnetic wave generation module 120, and adjust the impedance of the matching module 130 according to the load matching degree, so as to improve the absorption rate of the electromagnetic wave by the object to be processed 150 and increase the heating efficiency. The higher the load matching degree, the higher the ratio of the output power allocated from the electromagnetic wave generation module 120 to the cavity capacitor 110, indicating that the heating efficiency of the object to be processed 150 is higher when other conditions are the same.

[0030] The heating device 100 may include a bidirectional coupler connected in series between the cavity capacitor 110 and the electromagnetic wave generation module 120 in order to monitor in real time the forward power signal output by the electromagnetic wave generation module 120 and the reverse power signal returning to the electromagnetic wave generation module 120. The load matching degree may be the difference between 1 and the ratio of the reverse power signal to the forward power signal.

[0031] In particular, after determining the load matching degree of the electromagnetic wave generation module 120, if all the load matching degrees determined within a preset adjustment time are below the first matching threshold, the processing unit 141 controls to stop the operation of the electromagnetic wave generation module 120, avoiding continuous heating of the object to be processed 150 that contains many components with low electromagnetic wave absorption ability after its moisture changes from ice to liquid, further avoiding overheating of the object to be processed 150, ensuring the quality of the object to be processed 150, reducing waste of undesirable energy, and extending the service life of the electromagnetic wave generation module 120.

[0032] The processing unit 141 is configured to determine the load matching degree of the electromagnetic wave generation module 120 at preset time intervals. That is, if all the load matching degrees determined continuously a preset number of times are below the first matching threshold, it controls to stop the operation of the electromagnetic wave generation module 120.

[0033] When the load matching degree is below the first matching threshold, the processing unit 141 adjusts the impedance of the matching module 130 according to the load matching degree to ensure the absorption rate of the object to be processed 150 for electromagnetic waves.

[0034] Optionally, the load matching degree may be replaced by return loss. The lower the return loss, the higher the ratio of the output power allocated from the electromagnetic wave generation module 120 to the cavity capacitor 110, indicating that the heating efficiency of the object to be processed 150 is higher when other conditions are the same.

[0035] After determining the return loss of the electromagnetic wave generation module 120, if the return loss determined within a preset adjustment time is greater than a preset loss threshold, the processing unit 141 is configured to stop the operation of the electromagnetic wave generation module 120.

[0036] In some embodiments, the processing unit 141 determines a preset adjustment time according to the weight of the object to be processed 150, and improves the judgment accuracy of whether the heating of the object to be processed 150 is basically completed or there are components with low electromagnetic wave absorption ability.

[0037] The processing unit 141 aligns the preset adjustment time according to the preset weight-time correspondence relationship stored in the storage unit 142 according to the weight. Here, the preset adjustment times corresponding to different weights are recorded in the weight-time correspondence relationship. In order to correspond to different objects to be processed 150, the preset adjustment time has a positive correlation with the weight, and the electromagnetic wave generation module 120 can be stopped more accurately.

[0038] For example, in the weight-time correspondence relationship, the preset adjustment times corresponding to different weight intervals are recorded. The larger the intermediate value of the weight interval, the longer the corresponding preset adjustment time.

[0039] In some embodiments, during heating, the processing unit 141 determines the change rate of the dielectric constant of the object to be processed 150. When the change rate is less than or equal to the change rate threshold, it controls to stop the operation of the electromagnetic wave generation module 120, and in cooperation with the threshold judgment of the load matching degree, stops the object to be processed 150 accurately in the desired state of the user.

[0040] The processing unit 141 determines the change rate threshold according to the weight of the object to be processed 150, and improves the judgment accuracy of whether the heating is completed.

[0041] The processing unit 141 can adjust the change rate threshold according to a preset weight change rate control relationship. Here, different change rate thresholds corresponding to different weights are recorded in the weight change rate control relationship. The change rate threshold has a negative correlation with the weight for applying to the required amount of electromagnetic wave energy of different weighted objects to be processed 150, and the electromagnetic wave generation module 120 is stopped more accurately.

[0042] In some further embodiments, the weight of the object to be processed 150 is determined based on the initial impedance value of the matching module 130 that realizes the best load matching of the electromagnetic wave generation module 120, improving the accuracy of the weight and reducing the production cost.

[0043] Specifically, before controlling the electromagnetic wave generation module 120 to generate an electromagnetic wave signal with a preset heating power, the processing unit 141 controls the electromagnetic wave generation module 120 to generate an electromagnetic wave signal with a preset initial power, adjusts the impedance of the matching module 130, determines the impedance value of the matching module 130 at which the load matching degree of the electromagnetic wave generation module 120 is maximized, and then is configured to determine the weight based on the impedance value. Here, when multiple impedance values of the matching module 130 all result in the maximum load matching degree of the electromagnetic wave generation module 120, the weight is determined based on the maximum impedance value.

[0044] FIG. 3 is a schematic circuit diagram showing the matching module 130 according to an embodiment of the present invention. Referring to FIG. 3, in some embodiments, the matching module 130 includes a first matching unit 131 connected in series between the electromagnetic wave generation module 120 and the cavity capacitor 110, and a second matching unit 132 having one end electrically connected between the first matching unit 131 and the cavity capacitor 110 and the other end grounded.

[0045] The first matching unit 131 and the second matching unit 132 may each include a plurality of parallel-connected matching branches. Each matching branch includes a fixed capacitor and a switch, and the reliability and adjustment range of the matching module 130 can be improved while simplifying the circuit.

[0046] The first matching unit 131 is mainly used to adjust the resonance point frequency. The capacitance values of the fixed capacitors of the plurality of matching branches are different, and are respectively controlled by switches S1, S2,..., S a The second matching unit 132 is mainly used to further adjust the resonance point frequency and the resonance point amplitude. The capacitance values of the fixed capacitors of the plurality of matching branches are different, and are respectively controlled by switches K1, K2,..., K b

[0047] In some further embodiments, the processing unit 141 adjusts the on / off states of the switches K1, K2,..., K b in the second matching unit 132 by the dichotomy method, gradually reduces the capacitance value interval of the maximum load matching degree, determines the capacitance value of the second matching unit 132 that realizes the maximum load matching degree (the capacitance value of the second matching unit 132 is indicated by the switch number of the capacitance value of the second matching unit 132), and further determines the weight of the object 150 to be processed.

[0048] Exemplarily, the second matching unit 132 has 15 switches (i.e., b = 15) in the order of switches K1, K2,..., K 14 , K 15 . The processing unit 141 first turns on the switches K8, K 12 and K4 of the second matching unit 132, and repeatedly determines the load matching degree for the switches S1, S2,..., S a of the corresponding first matching unit 131 respectively. Since the load matching degree corresponding to the switch K 12 is the largest, the optimal value is determined between the switches K8 to K 15 , and the switches K 10 and K 14 ​Turn it on and for each corresponding switch S1, S2, …, S of the first matching unit 131 a Iterate each of them to determine the load matching degree, and thus determine the switch number of the second matching unit 132 that realizes the maximum load matching degree.

[0049] In some other further embodiments, the processing unit 141 divides the capacity value range of the second matching unit 132 into a plurality of sub-ranges, determines the maximum load matching degree among the intermediate values of the plurality of sub-ranges, iterates all the capacity values of this sub-range, and further determines the capacity value of the second matching unit 132 that realizes the maximum load matching degree, and is configured to determine the weight of the object to be processed 150.

[0050] Exemplarily, the second matching unit 132 has 15 switches (i.e., b = 15) in the order of switch K1, K2, …, K 14 , K 15 First, the processing unit 141 turns on switches K2, K4, K6, K8, K 10 , K 12 and K 14 of the second matching unit 132, and iterates each corresponding switch S1, S2, …, S of the first matching unit 131 to determine the load matching degree. Since the load matching degree corresponding to switch K a is the maximum, the optimal value is determined between switches K 12 ~K 11 ~K 13 , turns on switches K 11 and K 13 of the second matching unit 132, and iterates each corresponding switch S1, S2, …, S of the first matching unit 131 to determine the load matching degree, and determines the switch number of the second matching unit 132 that realizes the maximum load matching degree. a In some other embodiments, the weight of the object to be processed 150 can be detected by a weight sensor or manually input by the user.

[0051] In some other embodiments, the weight of the object to be processed 150 can be detected by a weight sensor or manually input by the user.

[0052] In some embodiments, the processing unit 141 is configured to control the operation of the electromagnetic wave generation module 120 to stop when the load matching degree is equal to or lower than a second matching threshold. Here, the second matching threshold may be less than the first matching threshold, which prevents the load matching degree from being too low due to the workpiece 150 being too heavy, too large, too light, or too small, and prevents a large amount of electromagnetic waves from being reflected back to the electromagnetic wave generation module 120, which may burn out the electromagnetic wave generation module 120 or pose a safety risk.

[0053] FIG. 4 is a schematic flowchart showing a control method for the heating device 100 according to an embodiment of the present invention (in the drawings of the specification of the present invention, "Y" indicates "yes" and "N" indicates "no"). Referring to FIG. 4, the control method for the heating device 100 of the present invention includes the following steps.

[0054] Step S402: Control the electromagnetic wave generation module 120 to generate an electromagnetic wave signal with a preset heating power. Step S404: Determine the load matching degree of the electromagnetic wave generation module 120 and adjust the impedance of the matching module 130 according to the load matching degree. Step S406: Determine whether any of the load matching degrees determined within a preset adjustment time is equal to or lower than a first matching threshold. If yes, execute step S408; if no, return to step S404. Step S408: Control the operation of the electromagnetic wave generation module 120 to stop.

[0055] The control method of the present invention determines the load matching degree after impedance adjustment. When all the load matching degrees continuously determined within a preset adjustment time are below a preset first matching degree, the operation of the electromagnetic wave generation module 120 is stopped. The object to be processed 150 containing many components with low electromagnetic wave absorption ability is prevented from being continuously heated after its moisture changes from ice to liquid, and further from being overheated, ensuring the quality of the object to be processed 150, reducing waste of undesirable energy, and extending the service life of the electromagnetic wave generation module 120.

[0056] The load matching degree of the electromagnetic wave generation module 120 may be determined at preset time intervals. That is, when all the load matching degrees continuously determined a preset number of times are below the first matching threshold, control is performed to stop the operation of the electromagnetic wave generation module 120.

[0057] When the load matching degree is below the first matching threshold, the impedance of the matching module 130 is adjusted according to the load matching degree to increase the absorption rate of the object to be processed 150 for electromagnetic waves.

[0058] In some embodiments, the preset adjustment time is determined based on the weight of the object to be processed 150, improving the judgment accuracy of whether the heating of the object to be processed 150 is basically completed or there are components with low electromagnetic wave absorption ability.

[0059] The preset adjustment time is obtained by matching according to the preset weight-time correspondence relationship in the storage unit 142 according to the weight. Here, the preset adjustment times corresponding to different weights are recorded in the weight-time correspondence relationship. To adapt to different objects to be processed 150 and stop the electromagnetic wave generation module 120 more accurately, the preset adjustment time has a positive correlation with the weight.

[0060] In some embodiments, the control method further includes determining a change rate of the dielectric constant of the object to be processed 150. When the change rate is less than or equal to a change rate threshold, the operation of the electromagnetic wave generation module 120 is controlled to stop, and in cooperation with the threshold determination of the load matching degree, the object to be processed 150 can be stopped in the desired state of the user.

[0061] The change rate threshold is determined according to the weight of the object to be processed 150, which improves the accuracy of determining whether the heating is completed.

[0062] The change rate threshold is obtained in accordance with a pre-set weight change rate control relationship corresponding to the weight. Here, different change rate thresholds corresponding to different weights are recorded in the weight change rate control relationship. Since the change rate threshold has a negative correlation with the weight to correspond to the required amount of electromagnetic wave energy for the object to be processed 150 with different weights, the electromagnetic wave generation module 120 can be stopped more accurately.

[0063] In some further embodiments, the weight of the object to be processed 150 is determined according to the initial impedance value of the matching module 130 that realizes the best load matching of the electromagnetic wave generation module 120, which improves the accuracy of the weight and reduces the production cost. Specifically, the weight of the object to be processed 150 is obtained by the following steps.

[0064] The electromagnetic wave generation module 120 is controlled to generate an electromagnetic wave signal with a pre-set initial power. Here, the pre-set initial power may be less than the pre-set heating power, thereby avoiding affecting the heating effect of the object to be processed 150 during the weight acquisition stage and reducing the damage to the electromagnetic wave generation module 120.

[0065] The impedance of the matching module 130 is adjusted to determine the impedance value of the matching module 130 at which the load matching degree of the electromagnetic wave generation module 120 is maximized.

[0066] Determine the weight according to the impedance value (in this step, if all the multiple impedance values of the matching module 130 result in the maximum load matching degree of the electromagnetic wave generating module 120, determine the weight according to the maximum impedance value).

[0067] In some embodiments, the control method further includes a step of controlling to stop the operation of the electromagnetic wave generating module 120 when the load matching degree is less than or equal to a second matching threshold. Here, the second matching threshold is smaller than the first matching threshold, which avoids the situation where the load matching degree caused by the object to be processed 150 with too large or too small weight or volume is too low, and also avoids the situation where a large amount of electromagnetic waves are reflected back to the electromagnetic wave generating module 120, burning out the electromagnetic wave generating module 120 or causing safety risks.

[0068] FIG. 5 is a detailed flowchart showing a control method for the heating device 100 according to an embodiment of the present invention. Referring to FIG. 5, the control method for the heating device 100 of the present invention specifically includes the following detailed steps.

[0069] Step S502: Obtain a heating command. Step S504: Control the electromagnetic wave generating module 120 to generate an electromagnetic wave signal with a preset initial power. Step S506: Adjust the impedance of the matching module 130 and determine the impedance value of the matching module 130 at which the load matching degree of the electromagnetic wave generating module 120 is maximized. Step S508: Determine the weight according to the impedance value of the matching module 130 at which the load matching degree of the electromagnetic wave generating module 120 is maximized, and further determine a preset adjustment time and a change rate threshold according to the weight. Step S510: Determine the load matching degree of the electromagnetic wave generating module 120 and the change rate of the dielectric constant of the object to be processed 150 at preset time intervals. Execute step S512 and step S520. Step S512: Determine whether the load matching degree is less than or equal to the second matching threshold. If yes, execute step S522; if no, execute step S514. Step S514: Determine whether the load matching degree is less than or equal to the first matching threshold. If yes, execute steps S516 and S518; if no, execute step S510. Step S516: Adjust the impedance of the matching module 130 according to the load matching degree. Step S518: Determine whether all the load matching degrees determined within the preset adjustment time are less than or equal to the first matching threshold. If yes, execute step S522; if no, return to step S510. Step S520: Determine whether the change rate of the dielectric constant of the object to be processed 150 is less than or equal to the change rate threshold. If yes, execute step S522; if no, return to step S510. Step S522: Control to stop the operation of the electromagnetic wave generation module 120. Return to step S502.

[0070] As described above, this specification comprehensively shows and describes multiple exemplary embodiments of the present invention. However, it should be understood by those skilled in the art that many variations and modifications in accordance with the principles of the present invention can be directly determined or inferred based on the disclosure of the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention is intended to cover all such variations and modifications.

Claims

1. A control method for a heating device, comprising an electromagnetic wave generation module that generates an electromagnetic wave signal for heating an object to be processed, and a matching module that adjusts the load impedance of the electromagnetic wave generation module by adjusting its own impedance, wherein: The control method comprises: Controlling the electromagnetic wave generation module to generate an electromagnetic wave signal with a preset heating power; Determining the load matching degree of the electromagnetic wave generation module, and adjusting the impedance of the matching module according to the load matching degree, in this order; The control method further comprises: When the load matching degrees determined within a preset adjustment time are all below a first matching threshold, controlling to stop the operation of the electromagnetic wave generation module; Determining the change rate of the dielectric constant of the object to be processed; Determining a change rate threshold according to the weight of the object to be processed; When the change rate is below the change rate threshold, controlling to stop the operation of the electromagnetic wave generation module; The determination of the load matching degree of the electromagnetic wave generation module is to determine the difference between 1 and the ratio of the reverse voltage signal to the forward power signal as the load matching degree; The forward power signal is the electromagnetic wave signal generated and output by the electromagnetic wave generation module; The reverse voltage signal is a signal that a part of the electromagnetic wave signal output by the electromagnetic wave generation module is reflected and returns to the electromagnetic wave generation module. A control method for a heating device, characterized by the above.

2. The step of determining the change rate threshold according to the weight of the object to be processed comprises: Matching the change rate threshold according to a preset weight change rate correspondence relationship according to the weight, The change rate thresholds corresponding to different weights are recorded in the weight change rate correspondence relationship, and the change rate threshold has a negative correlation with the weight. The control method according to claim 1.

3. Before the step of controlling the electromagnetic wave generation module to generate an electromagnetic wave signal with a preset heating power, Controlling the electromagnetic wave generation module to generate an electromagnetic wave signal with a preset initial power; Adjusting the impedance of the matching module, and determining the impedance value of the matching module when the load matching degree of the electromagnetic wave generation module is maximized; Determining the weight according to the impedance value. In the step of determining the weight according to the impedance values when all of the plurality of impedance values of the matching module are such that the load matching degree of the electromagnetic wave generation module is maximized, the weight is determined based on the maximum impedance value, according to the control method described in claim 1 or 2.

4. A control method for a heating device including an electromagnetic wave generation module that generates an electromagnetic wave signal for heating an object to be processed, and a matching module that adjusts the load impedance of the electromagnetic wave generation module by adjusting its own impedance, The control method includes: Controlling the electromagnetic wave generation module to generate an electromagnetic wave signal with a preset heating power; Determining the load matching degree of the electromagnetic wave generation module, and adjusting the impedance of the matching module according to the load matching degree, in this order; The control method includes: When all of the load matching degrees determined within a preset adjustment time are less than or equal to a first matching threshold, further including a step of controlling the operation of the electromagnetic wave generation module to stop; Determining the preset adjustment time according to the weight of the object to be processed, and Before the step of controlling the electromagnetic wave generation module to generate an electromagnetic wave signal with a preset heating power, Controlling the electromagnetic wave generation module to generate an electromagnetic wave signal with a preset initial power; Adjusting the impedance of the matching module, and determining the impedance value of the matching module when the load matching degree of the electromagnetic wave generation module is maximized; Including a step of determining the weight according to the impedance value; In the step of determining the weight according to the impedance values when all of the plurality of impedance values of the matching module are such that the load matching degree of the electromagnetic wave generation module is maximized, the weight is determined based on the maximum impedance value; The determination of the load matching degree of the electromagnetic wave generation module is to determine the difference between 1 and the ratio of the reverse voltage signal to the forward power signal as the load matching degree; The forward power signal is the electromagnetic wave signal generated and output from the electromagnetic wave generation module. The reverse voltage signal is a signal in which a part of the electromagnetic wave signal output from the electromagnetic wave generation module is reflected and returns to the electromagnetic wave generation module. A control method for a heating device, characterized in that.

5. The control method according to any one of claims 1 to 3, wherein the preset adjustment time is determined according to the weight of the object to be processed.

6. The step of determining the preset adjustment time according to the weight of the object to be processed is Including matching the preset adjustment time according to a preset weight-time correspondence relationship according to the weight, The control method according to claim 4 or 5, wherein preset adjustment times corresponding to different weights are recorded in the weight-time correspondence relationship, and the preset adjustment time has a positive correlation with the weight.

7. When the load matching degree is equal to or less than a second matching threshold value, the method further includes a step of controlling to stop the operation of the electromagnetic wave generation module, The control method according to any one of claims 1 to 6, wherein the second matching threshold value is smaller than the first matching threshold value.

8. The method further includes a step of determining a change rate of the dielectric constant of the object to be processed, The control method according to claim 4, wherein when the change rate is equal to or less than a change rate threshold value, the operation of the electromagnetic wave generation module is controlled to stop.

9. Determining the load matching degree of the electromagnetic wave generation module at preset time intervals, and / or The control method according to any one of claims 1 to 8, further including a step of adjusting the impedance of the matching module according to the load matching degree when the load matching degree is equal to or less than a first matching threshold value.

10. A cavity capacitor for placing an object to be processed, An electromagnetic wave generation module configured to generate an electromagnetic wave signal for heating the object to be processed in the cavity capacitor, A matching module configured to adjust the load impedance of the electromagnetic wave generation module by adjusting its own impedance, A heating device comprising a controller configured to execute the control method according to any one of claims 1 to 9.

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