A microwave combined with radio frequency heating device and a defrosting method

Abstract

This invention discloses a microwave combined with radio frequency heating device and thawing method, belonging to the fields of food processing and electromagnetic heating technology. The device includes a frame and a heating chamber mounted on it. Within the heating chamber, pairs of electrode plates connected to a multi-source radio frequency generator module are arranged in parallel, with a material tray positioned between the electrode plates. A driving mechanism is also provided within the heating chamber, with a microwave emitting module at its driving end. The driving mechanism drives the microwave emitting module to move within the heating chamber to change its microwave emission position. A hyperspectral camera is mounted on the side wall of the heating chamber to acquire spectral image information of the material to monitor quality changes. A sensor unit is also provided within the heating chamber. A control system is also included, electrically connected to the multi-source radio frequency generator module, the microwave emitting module, and the sensor unit. This invention achieves uniform and movable microwave field irradiation, combining dynamic synergistic control of radio frequency and microwave with hyperspectral quality monitoring, solving the problems of poor uniformity, localized overheating, and quality deterioration during thawing.

Description

Technical Field

[0001] This invention relates to the field of heating and defrosting equipment technology, specifically to a microwave combined with radio frequency heating device and defrosting method. Background Technology

[0002] Freezing is an important means of extending the shelf life of food, but frozen foods must be thawed before further processing or cooking. Traditional thawing methods, such as air thawing and brine thawing, suffer from problems such as slow speed, significant juice loss, and easy microbial growth. In recent years, dielectric heating thawing technology based on electromagnetic waves, especially microwave thawing and radio frequency thawing, has attracted widespread attention due to its ability to achieve volumetric heating and rapid thawing speed. However, during microwave thawing, because the dielectric loss factor of water is much greater than that of ice, the thawed areas absorb more microwave energy, leading to a sharp increase in local temperature, while the unthawed areas heat up slowly, resulting in a "thermal runaway" phenomenon, i.e., localized overheating. Although radio frequency thawing has a longer wavelength, greater penetration depth, and relatively uniform heating, the dielectric loss factor of the material changes significantly in the phase transition range (around -4°C), and the radio frequency energy coupling efficiency decreases, causing the overall temperature to stagnate near the phase transition region for a long time, resulting in a significant reduction in thawing efficiency.

[0003] Existing technologies have attempted to combine radio frequency (RF) and microwave technologies, such as the invention patent with publication number CN210670632U, which discloses a scheme to first thaw frozen items using an RF feed component, and then heat the thawed items using a microwave feed component. This method operates in a time-division multiplexing mode, mainly addressing the connection between thawing and subsequent heating, but it does not propose solutions to the uniformity challenges caused by changes in the dielectric properties of materials at different stages of the thawing process. Furthermore, some studies have proposed a three-stage combined dielectric heating thawing method (i.e., a combined scheme of RF, low-frequency microwave, and high-frequency microwave), but this scheme involves fixed timing switching and lacks dynamic and precise control over the thawing process and quality control.

[0004] Therefore, there is an urgent need for a device and method that can comprehensively utilize the advantages of radio frequency and microwave, and dynamically optimize according to the thawing process, so as to maximize the uniformity of thawing and reduce juice loss while ensuring speed. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a microwave combined with radio frequency heating device and thawing method, which solves the problems of poor uniformity, local overheating, uneven heating caused by fixed microwave field distribution, and quality deterioration during the thawing process. It achieves uniform and movable microwave field irradiation and maximizes the protection of food quality while ensuring thawing speed.

[0006] A microwave-radio frequency (RF) heating device includes a frame with a heating chamber on the frame. Parallel electrode pairs are arranged within the heating chamber, each connected to the output of a multi-source RF generator module. The parallel arrangement of the electrode pairs creates a relatively uniform electric field distribution within the heating chamber, enabling RF heating of the material. Utilizing the long wavelength penetration characteristics of RF, the material is preheated as a whole. A tray is positioned between the electrode pairs to hold the material to be thawed. A driving mechanism is installed within the heating chamber, with a microwave emitting module at its driving end. The driving mechanism moves the microwave emitting module within the heating chamber, changing its position relative to the thawing material to achieve uniform irradiation. By moving the microwave emitting module within the heating chamber, uniform and movable irradiation of the microwave field can be achieved to a certain extent, dynamically adjusting the spatial distribution of microwave energy on the material surface. This effectively avoids localized energy concentration caused by traditional fixed microwave sources, significantly improving thawing uniformity. A hyperspectral camera is installed on the side wall of the heating chamber to acquire spectral image information of the material to monitor changes in material quality. The hyperspectral camera can simultaneously acquire two-dimensional spatial images and continuous-band spectral information. It identifies material composition, state, and distribution through spectral "fingerprints," and monitors changes in nutrient content and surface moisture trends in real time, enabling online visual monitoring of thawing quality. The heating chamber is equipped with sensor units that work in conjunction with the material to collect real-time data on material temperature, mass, and environmental parameters. A control system is also included, electrically connected to the multi-source radio frequency generator module, microwave transmitter module, and sensor units.

[0007] Preferably, the driving mechanism includes a linear drive module vertically fixed on the side wall of the heating chamber. The moving end of the linear drive module is provided with a transverse support rod, a track is provided on the transverse support rod, and a support is slidably mounted on the track. The microwave emitting module is mounted on the support, and a driving mechanism for driving the support to move along the track is provided between the support and the transverse support rod. Vertical lifting is achieved through the linear drive module, and the cooperation between the support and the track allows the microwave emitting module to move flexibly within the heating chamber, further expanding the microwave coverage area and improving field uniformity.

[0008] Preferably, the transverse support rod is an arc-shaped or ring-shaped support rod, and the driving mechanism can drive the support to move in an arc or ring shape along the transverse support rod. The arc-shaped or ring-shaped transverse support rod allows the microwave transmitting module to move around the material circumferentially, realizing microwave energy incident from different angles, further dispersing standing wave hotspots, and improving the uniformity of microwave field distribution around the material circumferentially.

[0009] Preferably, the multi-source RF generation module includes an RF power supply fixedly mounted on a frame. The RF power supply is connected to an RF converter, which is electrically connected to an electrode plate to facilitate the control and stable output of the RF signal. The RF frequency generated by the RF converter includes at least two of 13.56MHz, 27.12MHz, and 40.68MHz; the microwave frequency generated by the microwave transmission module includes at least one of 214.5MHz, 433MHz, and 915MHz. By configuring multiple RF and microwave frequencies, the optimal frequency combination can be selected according to the material type, thickness, and thawing stage. For example, a lower frequency RF with deeper penetration can be used in the cryogenic stage, while a higher frequency microwave with higher coupling efficiency can be used in the phase transition stage, thus balancing penetration depth and heating efficiency.

[0010] Preferably, the bottom of the material tray is provided with a support column, which is slidably mounted on the frame. The electrode plate pair includes an upper electrode plate and a lower electrode plate arranged in parallel, with the material tray positioned between the upper and lower electrode plates. The lower electrode plate has a through hole for the support column to pass through. The sensor unit includes a gravity sensor fixedly mounted on the frame, with the lower end of the support column connected to the gravity sensor. The gravity sensor is used to measure the mass change of the material during the thawing process. The sensor unit also includes a temperature and humidity monitor fixedly mounted on the side wall of the heating chamber, which is used to monitor the temperature and humidity data inside the heating chamber. The sensor unit also includes an infrared temperature sensor array or fiber optic temperature sensor installed inside the heating chamber for real-time monitoring of the temperature distribution at different points on the material surface. Through the acquisition of multiple parameters such as gravity, temperature and humidity, and temperature distribution, a comprehensive data foundation is provided for closed-loop control. Among these parameters, mass change can indirectly reflect the degree of juice loss, and temperature distribution can identify the risk of local overheating.

[0011] Preferably, the hyperspectral camera is located outside the heating chamber, with its camera end extending into the chamber and facing the material. This allows for real-time acquisition of spectral image information of the material during the thawing process, and the transmission of this image information to the control system. Positioning the hyperspectral camera outside the heating chamber avoids interference from the high temperature, high humidity, and electromagnetic environment inside the chamber on the precision optical equipment, while the extended camera end ensures clear observation of the material.

[0012] Preferably, the control system includes a controller, which is connected to both the sensor unit and the hyperspectral image display screen.

[0013] A defrosting method based on the above-mentioned microwave combined radio frequency heating device includes the following steps:

[0014] Step S1: Initial Scan and Modeling: Place the material to be thawed in the tray, activate the sensor unit and the hyperspectral camera to perform an initial scan of the material, acquire initial spectral image information and temperature distribution information, and the control system generates a targeted initial thawing strategy based on the initial scan data, including radio frequency selection and initial power setting. Specifically, the control system is configured to dynamically adjust the start / stop and power of the multi-source radio frequency generation module, as well as the start / stop, power, and position of the microwave emission module based on the data collected by the sensor unit. This ensures penetration depth while utilizing the rapid heating characteristics of microwaves to break through the phase transition bottleneck, thereby avoiding juice loss and protein denaturation caused by local overheating.

[0015] Step S2: Cryogenic Segment Radio Frequency-Driven Defreezing: When the overall temperature of the material is below -5℃, the control system controls the multi-source radio frequency generator module to generate and preheat the entire material via radio frequency between the electrode pairs, causing the material temperature to rise rapidly and uniformly from the cryogenic zone. In this stage, the longer wavelength and greater penetration depth of the radio frequency are utilized to preheat the cryogenic material as a whole, effectively avoiding the risk of localized overheating caused by selective microwave heating in this stage, and ensuring that the material temperature rises uniformly to near the glass transition temperature.

[0016] Step S3: Multi-source synergistic defrosting during phase change: When the sensor unit detects that the temperature at any point on the material surface reaches the phase change range of -4℃, the control system controls the multi-source radio frequency (RF) generator module to reduce its power to the minimum. Simultaneously, the microwave transmitter module is activated to feed microwaves, and the drive mechanism moves the microwave transmitter module within the heating chamber. Microwaves are used for rapid heating, while RF is used to heat the still-frozen areas as a whole. The two work synergistically. During this stage, the RF maintains overall "heat preservation" of the frozen area at low power, while the microwave rapidly "attacks" the thawed areas at higher power. The drive mechanism moves the microwave transmitter module to change its emission position, dynamically optimizing the microwave field distribution, breaking through the defrosting bottleneck near -4℃, and preventing surface overheating and internal "half-cooked" phenomena.

[0017] Step S4: Endpoint Judgment and Termination: When the sensor unit detects that any temperature on the material surface reaches the preset thawing endpoint temperature of 0°C, thawing continues for a preset time. The material quality is confirmed by the hyperspectral camera, and the control system cuts off all power to complete the thawing. At the endpoint, the hyperspectral camera detects the nutrient content and moisture state on the material surface. Thawing ends after confirming there is no localized overheating, no significant juice seepage, and stable spectral characteristics, thus avoiding quality deterioration caused by over-thawing.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] This invention uses a drive mechanism to move the microwave emitting module within the heating chamber, dynamically changing the microwave emission position of the module relative to the material. This effectively avoids the localized energy concentration and standing wave hotspots caused by traditional fixed microwave sources, achieving a certain degree of uniform and movable microwave field irradiation and significantly improving the spatial uniformity of microwave heating. Simultaneously, based on the changes in the dielectric properties of the material at different temperature ranges during thawing, a dynamic control strategy of "RF-dominated cryogenic segment—RF-microwave synergistic phase transition segment" is adopted. While ensuring RF penetration depth, the rapid heating characteristics of microwaves are utilized to overcome the phase transition bottleneck, achieving dual optimization of thawing speed and uniformity.

[0020] Furthermore, through the coordinated operation of the sensor unit, hyperspectral camera, and control system, energy input can be precisely controlled based on the real-time temperature distribution, mass changes, and spectral characteristics of the material. This effectively avoids quality deterioration issues such as juice loss and protein denaturation caused by localized overheating, preserving the original color, taste, and nutrition of the food to the greatest extent possible. The optimal combination of radio frequency and microwave frequency can be flexibly selected according to the type, thickness, and thawing stage of the material, offering strong adaptability. Attached Figure Description

[0021] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the front structure of the present invention;

[0023] Figure 2 This is a schematic diagram of the control system layout of the present invention;

[0024] Figure 3 This is a three-dimensional structural diagram of the present invention;

[0025] Figure 4 This is a schematic diagram of the driving mechanism of the present invention;

[0026] In the diagram: 1-Frame, 2-Upper electrode plate, 3-Temperature and humidity monitor, 4-Horizontal support rod, 5-Plate, 6-Lower electrode plate, 7-Support column, 8-Gravity sensor, 10-RF converter, 11-RF power supply, 12-RF switch button, 13-Hyperspectral camera, 14-Power supply, 15-Microwave emission module, 16-Hyperspectral image display screen, 17-Controller, 19-Linear drive module, 20-Rail, 21-Support, 22-Roller, 23-Gear ring, 24-Motor. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1

[0029] A microwave combined with radio frequency heating device, such as Figure 1 , 3 As shown, the system includes a frame 1, on which a heating chamber formed by a metal plate is mounted, thereby utilizing the metal material to shield electromagnetic wave leakage. A pair of electrode plates are arranged parallel to each other within the heating chamber. Each electrode plate pair includes an upper electrode plate 2 and a lower electrode plate 6. The upper electrode plate 2 is fixed to the top of the heating chamber, and the lower electrode plate 6 is fixed to the bottom of the heating chamber. They are arranged parallel to each other and are electrically connected to the output terminal of an RF converter 10 via cables. The input terminal of the RF converter 10 is electrically connected to an RF power supply 11 fixed on the frame 1. The RF power supply and the RF converter together constitute a multi-source RF generation module. Specifically, in this embodiment, the RF power supply 11 can generate at least two RF frequencies selected from 13.56MHz, 27.12MHz, and 40.68MHz. The RF converter 10 switches between these frequencies to feed in different frequencies of RF energy.

[0030] A tray 5 is disposed between the electrode plates, and the tray 5 is used to hold the material to be thawed. A support column 7 is provided at the bottom of the tray 5. The lower end of the support column 7 extends out of the heating chamber and slides on the frame 1. The lower electrode plate 6 has a through hole for the support column 7 to pass through. After passing through the through hole in the lower electrode plate 6, the support column 7 slides with a guide sleeve at the bottom of the frame 1, allowing the tray 5 to move up and down between the upper electrode plate 2 and the lower electrode plate 6 to adjust the relative position of the material and the electrode plates. The lower end of the support column 7 is connected to a gravity sensor 8 fixedly mounted on the frame 1. The gravity sensor 8 is used to measure the mass change of the material during the thawing process in real time and feed it back to the control system.

[0031] In addition, such as Figure 4As shown, a driving mechanism is provided inside the heating chamber. The driving mechanism includes a linear drive module 19 vertically fixed on the side wall of the heating chamber. The linear drive module 19 can be a conventional motor screw linear module to achieve linear drive. The moving end of the linear drive module 19 is provided with a transverse support rod 4. A track 20 is provided on the transverse support rod 4, and a support 21 is slidably provided on the track 20. In this embodiment, a roller 22 is provided at the bottom of the support 21, and the roller cooperates with the track to achieve sliding. The microwave emitting module 15 is fixedly mounted on the support 21, and a driving mechanism for driving the support 21 to move along the track 20 is provided between the support 21 and the transverse support rod 4. The microwave emitting module 15 can generate at least one microwave frequency selected from 214.5MHz, 433MHz, and 915MHz. By combining the lifting movement of the linear drive module 19 with the translational movement of the support 21 along the track 20, the position of the microwave emitting module 15 in the two-dimensional plane inside the heating chamber can be adjusted, dynamically changing the microwave emission position relative to the material.

[0032] In one variation of this embodiment, the transverse support rod 4 is an arc-shaped or ring-shaped support rod. The driving mechanism drives the support 21 to move in an arc or ring shape along the transverse support rod 4, allowing the microwave emitting module 15 to move circumferentially around the material and feed microwave energy into the material from different angles. Specifically, in this embodiment, the driving mechanism includes a gear ring 23 disposed on the side wall of the track, and a motor 24 is disposed on the support. The output end of the motor 24 is provided with a gear for engaging with the gear ring 23. Thus, when it is necessary to drive the support to move along the track, the motor drives the gear to rotate, thereby changing the engagement position between the gear and the gear ring, and realizing position movement.

[0033] In addition, a hyperspectral camera 13 is installed on the outside of the heating chamber sidewall. The camera end of the hyperspectral camera 13 extends through the sidewall into the chamber and faces the material. It is used to acquire the spectral image information of the material in real time during the thawing process and transmit the image information to the control system. The hyperspectral camera 13 can simultaneously acquire two-dimensional spatial images of the material surface and fine spectral information in continuous bands. By identifying the composition, state, and distribution of the material through spectral "fingerprints," and combined with the gravity sensor 8 to measure the mass change of the material in real time during the thawing process, the changes in the material's moisture content can be obtained, thereby detecting changes in nutrient composition and surface moisture trends in real time.

[0034] Furthermore, the heating chamber is also equipped with a sensor unit that works with the material. The sensor unit includes a temperature and humidity monitor 3 fixedly installed on the side wall of the heating chamber for monitoring the temperature and humidity data inside the heating chamber; it also includes an infrared temperature sensor array or fiber optic temperature sensor installed inside the heating chamber for real-time monitoring of the temperature distribution at different points on the surface of the material.

[0035] In addition, such as Figure 2As shown, the control system includes a controller 17, which is electrically connected to the multi-source radio frequency generator module, microwave transmitter module 15, gravity sensor 8, temperature and humidity monitor 3, infrared temperature sensor array / fiber optic temperature sensor, and hyperspectral camera 13. The controller 17 is also connected to a hyperspectral image display screen 16, and its panel has a power button for controlling the start / stop of the radio frequency signals generated by the multi-source radio frequency generator module or for controlling the overall power supply. The controller 17 is configured to dynamically adjust the start / stop and power of the multi-source radio frequency generator module, as well as the start / stop, power, and position of the microwave transmitter module 15, based on data collected by the sensor units and the hyperspectral camera 13. The controller 17 can be processed by a conventional microcomputer or microcontroller and is electrically connected to a power supply 14 mounted on the frame.

[0036] As a further optional implementation, the support column includes an outer sleeve fixedly connected to the bottom of the tray and an inner support rod fixedly connected to the detection end of a gravity sensor. The outer sleeve is slidably fitted with a guide sleeve, and the outer sleeve and the inner support rod are threaded together. Rotating the outer sleeve can change the overall length of the support column, thereby allowing for fine-tuning of the tray's position to meet the thawing needs of materials of different sizes. Additionally, the RF power supply is electrically connected to an RF switching button 12 located on the frame, enabling manual RF switching capability.

[0037] Example 2

[0038] A method for defrosting using the microwave combined with radio frequency heating device described in Example 1 includes the following steps:

[0039] Step S1: Initial Scan and Modeling. The operator first places the material to be thawed into the tray 5, adjusting the height of the support column 7 to position the material appropriately between the upper electrode plate 2 and the lower electrode plate 6. The temperature and humidity monitor 3, infrared temperature sensor array / fiber optic temperature sensor, and hyperspectral camera 13 are activated to perform an initial scan of the material. The controller 17 is configured to dynamically control the start / stop and power of the multi-source radio frequency generation module, as well as the start / stop, power, and position of the microwave transmission module 15, based on the data collected by the sensor units and the hyperspectral camera 13. In actual use, the hyperspectral camera 13 acquires initial spectral image information of the material surface to identify the material's surface shape, color, and nutrient parameters; the infrared temperature sensor array and / or fiber optic temperature sensor acquire the initial temperature of the material surface and / or the internal temperature distribution; and the gravity sensor 8 acquires the initial mass of the material. The controller 17 integrates the above data to estimate the material's shape, volume, and thermal properties. After conducting small-batch tests on different material types, it obtains the corresponding set values ​​for each material type and generates an initial thawing strategy, including initial radio frequency selection and initial power setting.

[0040] When using a fiber optic temperature sensor to measure the internal temperature distribution of a material, holes are drilled at the corresponding locations on the material before processing begins, allowing the probe of the fiber optic temperature sensor to be inserted into the holes to measure the internal temperature.

[0041] Step S2: Cryogenic Segment RF-Driven Defreezing: When the infrared temperature sensor array / fiber optic temperature sensor detects that the overall material temperature is below -5℃, the controller 17 prioritizes the activation of the multi-source RF generation module, selecting an RF frequency with a larger penetration depth, and performing RF heating at the first power (e.g., 800W). The RF energy preheats the entire material through the electric field between the upper electrode 2 and the lower electrode 6. Utilizing the long wavelength penetration characteristic of RF, the material temperature is rapidly and uniformly increased from the cryogenic zone, effectively avoiding the risk of localized overheating caused by microwave selective heating during the cryogenic stage.

[0042] Step S3: Multi-source coordinated defrosting during the phase transition phase. When the infrared temperature sensor array / fiber optic temperature sensor detects that the temperature at any point on the material surface reaches the phase transition range of -4℃, the controller 17 automatically activates the coordinated mode: First, the RF power supply 11 is reduced to the lowest power condition (e.g., 200W) to maintain low-intensity heating of the material as a whole; simultaneously, the microwave transmitting module 15 is activated, an appropriate microwave frequency (e.g., 433MHz) is selected, and microwaves are fed in at a third power (e.g., 600W). The microwave transmitting module 15 is moved back and forth above the material by controlling the driving mechanism of the linear drive module 19 and the support 21. During this stage, the microwaves generated during the microwave movement rapidly heat the material, especially the high dielectric loss characteristics of the partially melted areas. At the same time, the RF is used to heat the areas that are still frozen. The combined effect of these two methods breaks through the defrosting bottleneck near -4℃. The movement of the microwave transmitting module 15 effectively avoids local energy concentration caused by a fixed microwave source, preventing surface overheating and the "half-cooked" phenomenon of unmelted interior. During the synergistic thawing phase, the hyperspectral camera 13 performs spectral imaging on the material surface at set time intervals (e.g., every 30 seconds) to monitor the trend of surface moisture changes and the status of nutrients.

[0043] Step S4: Endpoint Determination and Termination. When the infrared temperature sensor array / fiber optic temperature sensor detects that the temperature at any point on the material surface reaches the preset thawing endpoint temperature of 0°C, the controller 17 continues to maintain the current thawing process for the preset duration (e.g., five minutes). During this period, the hyperspectral camera 13 scans the entire surface of the material, analyzes the uniformity of surface moisture distribution and the stability of nutrient components, and confirms that there is no local overheating, no significant juice seepage, and the spectral characteristics are stable. Then, the controller 17 cuts off all radio frequency and microwave power, and thawing is complete.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A microwave combined with radio frequency heating device, comprising a frame (1), wherein a heating chamber is provided on the frame (1), characterized in that: The heating chamber is provided with parallel electrode plates, which are respectively connected to the output end of the multi-source radio frequency generation module; a material tray (5) is provided between the electrode plates, which is used to hold the material to be thawed; The heating chamber is equipped with a driving mechanism (4), and the driving end of the driving mechanism is equipped with a microwave emitting module (15). The driving mechanism is used to drive the microwave emitting module (15) to move within the heating chamber and change the microwave emitting position of the microwave emitting module (15) relative to the thawing material. The side wall of the heating chamber is equipped with a hyperspectral camera (13), which is used to acquire spectral image information of the material to monitor changes in material quality. The heating chamber is equipped with a sensor unit that works with the material. It also includes a control system, which is electrically connected to the multi-source radio frequency generation module, the microwave transmission module (15) and the sensor unit respectively.

2. The microwave combined radio frequency heating device according to claim 1, characterized in that, The driving mechanism includes a linear drive module (19) vertically fixed on the side wall of the heating chamber. The moving end of the linear drive module (19) is provided with a horizontal support rod (4). A track (20) is provided on the horizontal support rod (4), and a support (21) is slidably provided on the track (20). The microwave transmitting module (15) is provided on the support (21), and a driving mechanism for driving the support (21) to move along the track (20) is provided between the support (21) and the horizontal support rod (4).

3. The microwave combined radio frequency heating device according to claim 2, characterized in that, The transverse support rod (4) is an arc-shaped or ring-shaped support rod, and the driving mechanism can drive the support (21) to move in an arc or ring shape along the transverse support rod (4).

4. The microwave combined radio frequency heating device according to claim 1, characterized in that, The multi-source radio frequency generation module includes a radio frequency power supply (11) fixed on the frame (1), the radio frequency power supply (11) is connected to a radio frequency converter (10), and the radio frequency converter (10) is electrically connected to the electrode plate.

5. The microwave combined radio frequency heating device according to claim 4, characterized in that, The radio frequency generated by the radio frequency converter includes at least two of 13.56MHz, 27.12MHz and 40.68MHz; the microwave frequency generated by the microwave transmitting module (15) includes at least one of 214.5MHz, 433MHz and 915MHz.

6. The microwave combined radio frequency heating device according to any one of claims 1 to 5, characterized in that, The bottom of the tray (5) is provided with a support column (7), which is slidably mounted on the frame (1). The electrode plate pair includes an upper electrode plate (2) and a lower electrode plate (6) arranged in parallel. The tray (5) is located between the upper electrode plate (2) and the lower electrode plate (6). The lower electrode plate (6) is provided with a through hole that allows the support column (7) to pass through.

7. The microwave combined radio frequency heating device according to claim 6, characterized in that, The sensor unit includes a gravity sensor (8) fixedly mounted on the frame (1), and the lower end of the support column (7) is connected to the gravity sensor (8). The gravity sensor (8) is used to measure the mass change of the material during the thawing process. The sensor unit also includes a temperature and humidity monitor (3) fixedly mounted on the side wall of the heating chamber. The temperature and humidity monitor (3) is used to monitor the temperature and humidity data in the heating chamber. The sensor unit also includes an infrared temperature sensor array or a fiber optic temperature sensor installed in the heating chamber.

8. The microwave combined radio frequency heating device according to claim 1, characterized in that, The hyperspectral camera (13) is located outside the heating chamber, with its camera end extending into the heating chamber and facing the material.

9. The microwave combined radio frequency heating device according to claim 1, characterized in that, The control system includes a controller (17), which is connected to the sensor unit and the hyperspectral image display screen (16).

10. A defrosting method based on the microwave combined radio frequency heating device according to any one of claims 1 to 9, characterized in that, Includes the following steps: Step S1: Initial scanning and modeling: Place the material to be thawed in the tray (5), start the sensor unit and the hyperspectral camera (13) to perform an initial scan of the material, and obtain the initial spectral image information and temperature distribution information of the material; configure the control system to dynamically adjust the start-up and shutdown and power of the multi-source radio frequency generation module, as well as the start-up, shutdown, power and position of the microwave transmission module (15) according to the data collected by the sensor unit; Step S2: Cryogenic Section Radio Frequency Dominated Defreezing: When the overall temperature of the material is below -5℃, the control system controls the multi-source radio frequency generation module to generate and preheat the material with radio frequency between the electrode plates, so that the material temperature can be rapidly and uniformly increased from the cryogenic zone. Step S3: Phase change segment multi-source synergistic defrosting: When the sensor unit detects that the temperature at any point on the material surface reaches the phase change range of -4℃, the control system controls the multi-source radio frequency generation module to reduce to the minimum power, and at the same time starts the microwave emission module (15) to feed microwaves, and drives the microwave emission module (15) to move back and forth in the heating chamber through the drive mechanism to change the position of the microwave emission module (15), use microwaves to heat quickly, and use radio frequency to heat the area that is still in a frozen state as a whole, and the two work together; Step S4: Endpoint Judgment and End: When the multi-parameter sensing unit (4) detects that the material surface temperature reaches the preset thawing endpoint temperature of 0°C, it continues to thaw for a preset time. The material quality is confirmed by the hyperspectral camera (13), and the control system controls the cutting off of all power supplies to complete the thawing.

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