A microwave heating controllable power source and method for tobacco extraction

Abstract

This invention discloses a controllable microwave heating power source and method for tobacco extraction, comprising: a microwave power module for generating and modulating microwave energy; a central control module connected to the microwave power module; a sensing and monitoring module connected to the central control module for real-time monitoring of material temperature and stirrer speed; and an auxiliary support module. The central control module is configured to perform closed-loop control of the microwave power module based on temperature data from the sensing and monitoring module and return loss data detected by the microwave power module, thereby executing a customized temperature curve. By integrating microwave power modulation, multi-sensor monitoring, and intelligent control, it achieves precise temperature control, uniform heating, and flexible process adaptation during the tobacco material heating process, significantly improving the extraction efficiency and quality of tobacco aroma substances.

Description

Technical Field

[0001] This invention relates to the field of tobacco processing equipment technology, specifically to a microwave heating controllable power source for extracting tobacco aroma substances. Background Technology

[0002] In the tobacco industry's production and research activities, the extraction quality of tobacco aroma substances (such as damascone and chlorogenic acid) directly determines the flavor profile of tobacco products. Industry statistics show that high-quality aroma extracts can improve the sensory score of cigarette products by 15%-20%, while simultaneously driving market premiums for downstream products such as tobacco flavorings and heated cigarette e-liquids to over 10%. Therefore, efficient and precise extraction technology has always been one of the core directions of industry research and application. Currently, commonly used techniques in the field of tobacco aroma substance extraction mainly include traditional hot reflux extraction, ultrasound-assisted extraction, and conventional microwave extraction. However, these technologies still have significant shortcomings in practical applications, making it difficult to meet the industry's needs for precise control and efficient production during the extraction process.

[0003] From the perspective of industrial production, traditional hot reflux extraction technology is currently the mainstream choice for small and medium-sized tobacco processing enterprises. It relies on external heat sources such as steam or electric heating to conduct heat through the container wall, with a heating efficiency of only 30%-40% (far lower than the ideal extraction efficiency of 60%). Moreover, a "temperature gradient difference" with regional temperature differences of no more than 10℃ is prone to occur within the reactor. Taking an industrial reactor of no less than 50L as an example, the temperature fluctuation of tobacco material near the inner wall of the reactor is prone to exceed the control requirement of a temperature accuracy of no more than ±4℃, resulting in the carbonization or oxidation of heat-sensitive aroma substances (such as geraniol) and a high loss rate. In the central area of ​​the reactor, the material temperature uniformity is insufficient, and the release rate of aroma substances is limited, ultimately causing the dual problems of low extraction efficiency and high loss rate of effective ingredients. Meanwhile, the technology cannot flexibly adjust the heating curve. When switching tobacco varieties (such as from flue-cured tobacco to burley tobacco) or processing materials with different moisture contents (such as 12% and 18% moisture contents), it is necessary to stop the machine to replace the heating module or adjust the steam pressure. Each adjustment takes 1-2 hours, which seriously affects the continuity of production. Based on an average daily production of 8 hours, this will result in the loss of at least 150 hours of effective production time for the company each year, increasing labor and energy costs by about 20%.

[0004] In scientific research, ultrasonic-assisted extraction (ALE) technology is widely used in tobacco chemistry laboratories for aroma substance separation experiments due to its relatively low equipment cost (approximately 10,000-30,000 RMB per experimental unit). However, this technology has low temperature control precision, with a temperature error of ±4℃, and can only achieve constant temperature heating or "step-wise coarse temperature control," meaning that different temperature levels are maintained for a period of time. Since ALE cannot achieve rapid temperature changes, this holding time is usually greater than 30 minutes. This low control particle size makes it impossible to simulate the complex temperature change process of "gradient heating + multi-stage constant temperature" in industrial production (e.g., 25℃→50℃ (10 minutes)→65℃ (20 minutes)→80℃ (15 minutes)). Experimental data from a tobacco research institute shows that the composition ratio of aroma substances obtained by ultrasonic-assisted extraction deviates by 18%-22% from the results of industrial thermal reflux extraction. This means that the experimental data cannot directly provide a reliable basis for optimizing the production process, requiring multiple "experiment-production" comparative verifications, extending the research and development cycle by 30%-50%.

[0005] Microwave heating extraction technology has solved the problem of heat conduction efficiency (improving heating efficiency to 55%-60%), and is currently a promising solution for extracting tobacco aroma substances. However, in most existing technical embodiments, the controller of the microwave heating extraction device can only adjust the microwave power and lacks the function of automatically executing microwave heating extraction based on the preset temperature curves customized by tobacco researchers. The experimental repeatability is poor (parallel sample deviation rate of 10%-15%), and the heating rate cannot meet the flexible control requirements of 0-20℃ / min, making it difficult to cover the extreme working conditions in processes such as tobacco dry distillation where the maximum material temperature can reach 300℃.

[0006] While existing microwave extraction technologies have improved heating efficiency, most devices can only adjust microwave power and lack the ability to automatically adjust heating parameters based on the material's condition. A search revealed that patent CN106500143A determines the load level by detecting return loss to adjust microwave output, but it does not involve material temperature detection at all; patent CN105276640B, although including a temperature sensor, is only used to monitor the microwave source and circulator temperature to protect the equipment, rather than controlling the material heating process.

[0007] With the increasing demands for extraction precision and process flexibility in the tobacco industry, there is an urgent need for a microwave heating power source that can accurately control material temperature, achieve uniform heating, and support complex temperature profiles. Summary of the Invention

[0008] The present invention aims to overcome the shortcomings of the prior art and provide a controllable power source for microwave heating. By integrating microwave power modulation, multi-sensor monitoring and intelligent control, it achieves precise temperature control, uniform heating and flexible process adaptation for the heating process of tobacco materials, and significantly improves the extraction efficiency and quality of tobacco aroma substances.

[0009] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A microwave heating controllable power source for extracting tobacco aroma substances is characterized by comprising: a microwave power module for generating and modulating microwave energy; a central control module connected to the microwave power module; a sensing and monitoring module connected to the central control module for real-time monitoring of material temperature and stirrer speed; and an auxiliary support module; wherein the central control module is configured to perform closed-loop control of the microwave power module based on the temperature data from the sensing and monitoring module and in conjunction with the return loss data detected by the microwave power module, to execute a customized temperature curve.

[0010] Furthermore, the microwave power module includes: a microwave generating module, consisting of a magnetron and a frequency stabilization circuit; a microwave modulation module, designed based on the injection lock principle, including a voltage-controlled oscillator (VCO), used to receive signals from the central control module to adjust the frequency and amplitude of the output microwave; and a return loss detection module, including a directional coupler and a power detection module, used to measure the return loss value (S11 parameter) and its corresponding operating frequency and report it to the central control module.

[0011] Furthermore, the central control module is further configured to: calculate the dielectric constant and loss tangent of the material based on the S11 parameters and operating frequency reported by the return loss detection module, and adjust the output target of microwave power and frequency based on the changes in the dielectric constant and loss tangent.

[0012] Furthermore, the sensing and monitoring module includes a temperature sensor with a temperature measurement accuracy of no more than ±4℃ and a sampling frequency of no less than 1 time / second; and the central control module is further configured to dynamically adjust the microwave power through a PID algorithm so that the material temperature rise rate is controllable within the range of 0-20℃ / min during the heating stage, and to maintain the temperature error during the constant temperature stage not exceeding ±4℃.

[0013] Furthermore, the central control module is further configured to automatically adjust the microwave output to balance the radiation intensity when a temperature difference between different areas exceeds 10°C.

[0014] Furthermore, the auxiliary support module includes a microwave leakage detector and a metal shielding shell; the central control module is further configured to immediately cut off the power supply to the microwave power module when the detected microwave leakage exceeds 0.4W / m².

[0015] Furthermore, the auxiliary support module includes a backup power supply; the central control module is further configured to automatically save the current process data and unfinished temperature curve parameters using the backup power supply in the event of a sudden power outage.

[0016] A microwave heating method includes the following steps: S1: parameter preset, inputting process parameters including multiple custom temperature curves; S2: heating regulation, dynamically adjusting microwave power through closed-loop control based on real-time monitored material temperature to make the temperature follow the preset curve; simultaneously, inverting the dielectric properties of the material based on real-time monitored microwave return loss data, and adjusting the control parameters accordingly; S3: anomaly handling, including temperature anomaly handling, microwave leakage and pressure anomaly handling, and sudden power outage and data protection handling.

[0017] Furthermore, step S2 is further configured as follows: the dielectric constant and loss tangent of the material are calculated by inversion based on the return loss value (S11) and the operating frequency; based on the changes in the dielectric constant and loss tangent, the pre-stored PID parameter group is switched or the target settings of microwave power and frequency are updated.

[0018] Furthermore, the abnormal temperature handling in step S3 includes: if the material temperature exceeds 300°C, immediately reduce the microwave power to zero and forcefully dissipate heat; if it does not return to a safe range within 1 minute, cut off the microwave power supply.

[0019] This invention has three prominent innovative features: This power source constructs a dual control system combining "temperature closed-loop feedback" and "return loss-material state closed-loop sensing." It not only achieves precise temperature control through a high-precision temperature sensor and PID algorithm, but also innovatively utilizes return loss (S11 and frequency) to invert the dielectric constant and loss tangent of the material in real time, dynamically identifying the material's heating state and proactively adjusting microwave power and frequency accordingly. This achieves a leap from "passive temperature control" to "active sensing and intelligent temperature control."

[0020] The innovative state-sensing technology of this power source combines return loss detection with material state identification. By monitoring the frequency and S11 parameter changes of the return loss, the changing trends of the dielectric constant and loss tangent are inferred, thereby determining the heating state of the material and dynamically optimizing the microwave power and frequency output to achieve intelligent heating control.

[0021] This power source also features an innovative safety system, which includes an electromagnetic and operational safety system that meets national standards. It also integrates multiple safety mechanisms such as over-temperature protection, abnormal pressure handling, and data protection in case of sudden power failure, forming a complete safety protection system. Attached Figure Description

[0022] The above description of the present invention and the following detailed embodiments will be better understood when read in conjunction with the accompanying drawings. It should be noted that the drawings are merely examples of the claimed technical solutions.

[0023] Figure 1 This is a system block diagram of a controllable power source according to an embodiment of the present invention; Figure 2 This is a system block diagram of a microwave power module according to an embodiment of the present invention; Figure 3 This is a schematic diagram of a custom temperature curve in one embodiment of the present invention.

[0024] The reference numerals in the attached figures are explained as follows: 1. Microwave Power Module 101 Microwave Generator Module 102 Microwave Modulation Module 103 Return Loss Detection Module 2. Central Control Module 3. Sensing and Monitoring Module 4. Auxiliary support module Detailed Implementation

[0025] The following detailed description of the features and advantages of the present invention is sufficient to enable any person skilled in the art to understand the technical content of the present invention and implement it accordingly. Furthermore, based on the specification, claims and drawings disclosed herein, those skilled in the art can easily understand the related objects and advantages of the present invention.

[0026] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] For ease of understanding, the directional terms such as "upper," "lower," "top," and "bottom" used in this manual are based on the upright position of the aerosol generating device.

[0028] like Figure 1As shown, this invention discloses a microwave heating controllable power source for tobacco extraction. By integrating microwave power modulation, multi-sensor monitoring and intelligent control, it achieves precise temperature control, uniform heating and flexible process adaptation for the heating process of tobacco materials, significantly improving the extraction efficiency and quality of tobacco aroma substances.

[0029] The power source includes a microwave power module 1, a central control module 2, a sensing and monitoring module 3, and an auxiliary support module.

[0030] like Figure 2 As shown, the microwave power module 1 is used to generate and modulate microwave energy. It includes a microwave generation module 101, a microwave modulation module 102, and a return loss detection module 103. The microwave generation module consists of a magnetron and a frequency stabilization circuit. The magnetron has a specific output frequency variation range, which can cover multiple operating frequencies required by the microwave heating system. The function of the frequency stabilization circuit is to constrain the frequency jitter of the magnetron output within a predetermined range to ensure stable system operation. The microwave modulation module 102 is designed based on the injection lock principle. After the user determines the operating frequency, the control signal is converted into the control voltage of the voltage-controlled oscillator (VCO), which will adjust the small signal frequency output by the VCO.

[0031] The microwave modulation module 102 includes a voltage-controlled oscillator (VCO) circuit. After the user sets the operating frequency, the control signal is converted into a control voltage for the VCO. This voltage precisely adjusts the small-signal frequency output by the VCO. A small portion of the magnetron's output frequency is split off via a coupler for return loss detection, and then circulated to flow unidirectionally to the radiator, further reducing return loss and generating a stable output locked near the small-signal frequency. The return loss detection module 103 includes a reverse coupling branch and a power detection module. The reverse coupling branch couples a portion of the power from the power output path to the input of the power detection module via a directional coupler. The power detection module accurately measures the return loss value, i.e., the S11 parameter, and its corresponding operating frequency, and reports these measurements to the central control module 2 in real time. The frequency stabilization circuit and injection lockout design used in the microwave power module 1 effectively suppress magnetron frequency drift and reduce thermal stress on the power devices caused by frequency detuning. Meanwhile, by monitoring microwave leakage and temperature anomalies in real time, the system promptly implements power reduction or power-off protection, avoiding damage to key components such as magnetrons and circulators under abnormal operating conditions, and significantly improving the overall service life of the equipment.

[0032] Central control module 2 adopts an embedded control system architecture. The main controller uses an industrial-grade PLC or high-performance MCU as its processing core, with internally embedded temperature control algorithms and microwave parameter adjustment logic. It can receive external commands, including parameters such as target temperature, heating time, and holding time, and convert them into control signals to output to each execution unit. The human-machine interface unit uses a touch screen or button panel as input devices, connected to the main controller via a standard industrial communication protocol. It provides a graphical interface for users to input custom temperature curve parameters, including segmented temperature values, holding time for each temperature segment, and heating rate. Simultaneously, it displays key operating parameters such as current material temperature, microwave power, heating time, and stirrer speed in real time. Central control module 2 is configured to be based on... The temperature data from the sensing module 3, combined with the return loss data detected by the microwave power module 1, is used to perform closed-loop control on the microwave power module 1 to execute a custom temperature curve. Specifically, the central control module 2 calculates the dielectric constant and loss tangent of the material based on the S11 parameters and operating frequency reported by the return loss detection module 103, and adjusts the output targets of microwave power and frequency based on the changes in dielectric constant and loss tangent. The microwave power is dynamically adjusted through the built-in PID temperature control algorithm to make the temperature rise rate of the material controllable within the range of 0-20℃ / min during the heating stage, and to maintain the temperature error during the constant temperature stage not exceeding ±4℃. When the temperature difference between different areas exceeds 10℃, the microwave output is automatically adjusted to balance the radiation intensity.

[0033] The sensing and monitoring module 3 includes various detection devices. Temperature sensors, such as platinum resistance temperature sensors or infrared temperature sensors, are installed on the inner wall of the reactor or near the material. These sensors have a sampling frequency of at least 1 time per second and a temperature measurement accuracy of no more than ±4℃, ensuring the timeliness and accuracy of temperature data. The stirrer speed sensor is installed on the stirrer drive shaft and uses magnetic encoder or photoelectric encoder technology to monitor the stirrer speed at a frequency of at least 1 time per second, transmitting the real-time speed data to the main controller. The microwave power module 1 supports multi-frequency output and dynamic power adjustment. Combined with the coordinated control of the stirrer, the system can achieve zoned control of microwave energy in three-dimensional space. When the sensing and monitoring module 3 detects uneven temperature field distribution, the system adjusts the radiation parameters of different antenna elements to stabilize the material's thermal variation within 10℃, thereby ensuring the consistency of component extraction rate and aroma composition in the same batch of tobacco material.

[0034] The auxiliary support module 4 provides operational assurance for the system. The heat dissipation unit adopts air cooling or water cooling. Cooling fans or miniature water-cooled plates are installed near the microwave generator unit and the main controller to effectively remove the heat generated by the electronic components during operation. The power supply module provides a suitable and stable power supply for each functional module. The microwave generator unit requires a high-voltage power supply, while the controller requires a low-voltage DC power supply. This module has built-in overvoltage protection and overcurrent protection circuits. The outer shell and fixing structure are made of stainless steel and other metal materials, which provide both mechanical support and microwave shielding. The auxiliary support module 4 also includes a microwave leakage detector. When the detected microwave leakage exceeds 0.4W / m², the central control module 2 immediately cuts off the power supply to the microwave power module 1. The auxiliary support module 4 also includes a backup power supply. In the event of a sudden power failure, the central control module 2 uses the backup power supply to automatically save the current process data and the parameters of the incomplete temperature curve.

[0035] This power source constructs a dual control system combining "temperature closed-loop feedback" and "return loss-material state closed-loop sensing." It not only achieves precise temperature control through a high-precision temperature sensor and PID algorithm, but also innovatively utilizes return loss (S11 and frequency) to invert the dielectric constant and loss tangent of the material in real time, dynamically identifying the material's heating state and proactively adjusting microwave power and frequency accordingly. This achieves a leap from "passive temperature control" to "active sensing and intelligent temperature control."

[0036] The innovative state-sensing mechanism of this power source combines return loss detection with material state recognition. By monitoring changes in the frequency and S11 parameter of the return loss, it infers the changing trends of the dielectric constant and loss tangent, thereby determining the material's heating state and dynamically optimizing microwave power and frequency output for intelligent heating control. For example, it dynamically identifies the state changes of tobacco at different stages of heating (such as the moisture evaporation period and the aroma substance extraction period). Based on this, the central control module 2 proactively adjusts the microwave power and frequency to avoid localized overheating or underheating caused by sudden changes in the material's dielectric properties, effectively preventing the carbonization or oxidation of heat-sensitive aroma substances (such as damascone and chlorogenic acid) and ensuring the flavor integrity of the extract.

[0037] This invention also discloses a method for microwave heating using a controllable power source, including parameter presetting, heating regulation, and anomaly handling steps. In the parameter presetting stage, the user inputs extracted process parameters through a human-machine interface unit, including custom temperature curve parameters, setting segmented target temperatures and holding times according to a time series (e.g., ...). Figure 3As shown, the system supports multi-segment temperature curve settings, with each segment's temperature adjustment range from room temperature to 300℃ and a time adjustment accuracy of 1 minute. Material adaptation parameters are implemented through the system's built-in lookup table database, which stores the recommended initial microwave power values, PID parameter preset groups, and maximum safe power limits corresponding to different material types, weights, and moisture contents. Safety control parameters include the microwave leakage safety threshold, the reactor's maximum safe temperature, and the stirring speed range. After parameter input, the main controller automatically executes the system self-test process, detecting whether the current temperature and input power of the microwave generating unit are abnormal, verifying whether the temperature sensor sampling data is within the valid range, checking whether the stirrer can operate at the preset speed, and confirming that the heat dissipation unit and power module are in normal standby mode. After all components pass the self-test, the system enters the standby state.

[0038] During the heating and control phase, once the user initiates the heating process, the main controller coordinates the operation of each module, achieving intelligent control through a basic temperature control closed loop and material state perception and forward-looking control based on return loss. In the basic temperature control closed loop, the main controller controls the microwave generating unit to output energy according to the initial power through the microwave control unit. The temperature sensor collects the real-time temperature of the material at a frequency of 1 time / second and provides feedback. The main controller dynamically adjusts the microwave power through a built-in PID temperature control algorithm, driving the actual temperature to follow the preset curve. In the material state perception and forward-looking control based on return loss, the return loss detection module 103 continuously monitors the reflected power, calculates and reports the return loss value S11 parameter and its corresponding operating frequency in real time. The algorithm built into the central control module 2 calculates the dielectric constant and loss tangent of the tobacco material in real time based on the change curves of S11 and frequency data. The dielectric constant reflects the material's ability to store microwave energy, and the loss tangent reflects the material's ability to convert electromagnetic energy. In terms of thermal energy conversion, these two parameters dynamically decrease as moisture evaporates and aroma compounds are released during the heating process. The controller compares the inverted parameters with the pre-stored feature model to determine the current macroscopic state of the material, such as the initial heating period, the rapid moisture evaporation period, the main aroma compound release period, and the period approaching carbonization risk. Based on this state judgment, the controller will proactively fine-tune or reset the parameters of the PID controller, or even directly give a better power or frequency output target. For example, when the system determines that the material has entered the rapid water loss stage through return loss, it will slightly reduce the power in advance to avoid local overheating that may be caused by sudden changes in the medium characteristics. Conversely, when it determines that the material temperature uniformity has begun to decrease, it will automatically fine-tune the microwave frequency to change the heating range and balance the temperature field. During collaborative execution, the stirrer runs continuously throughout the process to ensure that the material is heated evenly. The main controller records the temperature-power-time-return loss S11 data every 2 minutes to form a complete process log.

[0039] During the anomaly handling phase, the system establishes a multi-level safety protection mechanism, specifically including temperature anomaly handling, microwave leakage and pressure anomaly handling, and sudden power outage and data protection handling. Temperature anomaly handling includes: when the material temperature exceeds the preset maximum safe temperature of 300℃, the central control module 2 immediately triggers an emergency power reduction command, reducing the microwave power to zero and simultaneously activating powerful cooling. If the temperature does not drop to the safe range within one minute, the power supply to the microwave power module 1 is automatically cut off. Additionally, if the temperature sensor detects abnormal data for 5 consecutive seconds, the central control module 2 determines it as a sensor malfunction, immediately reduces the microwave power to 50% of the initial power, and prompts for sensor inspection. Microwave leakage and pressure anomaly handling includes: when the microwave leakage detector detects a leakage exceeding the safe threshold of 0.4W / m², the central control module 2 immediately cuts off the power supply to the microwave power module 1 and stops microwave radiation; and when the system's pressure sensor detects abnormal pressure inside the reactor, it automatically opens the pressure relief valve at the top of the reactor, simultaneously reducing the microwave power by 20%. After the pressure returns to normal, the pressure relief valve is closed, and the original power level is restored. The emergency power outage and data protection mechanism includes the immediate activation of the system's built-in 30-minute backup power supply in the event of a power outage. The central control module 2 automatically saves the current temperature, time, power data, and parameters of any incomplete temperature curves, ensuring no process data is lost and providing an option to continue execution after power is restored. This anomaly handling mechanism, through multiple safety safeguards, ensures that the equipment complies with electromagnetic radiation safety standards, effectively prevents material carbonization loss, guarantees the integrity of process data, and significantly improves the reliability of equipment operation and process continuity.

[0040] The terminology and expressions used herein are for descriptive purposes only, and the invention should not be limited to these terms and expressions. The use of these terms and expressions does not imply the exclusion of any illustrative and descriptive equivalents (or parts thereof), and it should be recognized that various modifications that may exist should also be included within the scope of the claims. Other modifications, variations, and substitutions may also exist. Accordingly, the claims should be considered to cover all such equivalents.

[0041] Similarly, it should be noted that although the present invention has been described with reference to the specific embodiments described above, those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and various equivalent changes or substitutions can be made without departing from the spirit of the present invention. Therefore, any changes or modifications to the above embodiments within the scope of the essential spirit of the present invention will fall within the scope of the claims of the present invention.

Claims

1. A microwave heating controllable power source for tobacco extraction, characterized in that, include: Microwave power module, used to generate and modulate microwave energy; The central control module is connected to the microwave power module; The sensing and monitoring module is connected to the central control module and is used to monitor the material temperature and the agitator speed in real time. And auxiliary support modules; The central control module is configured to perform closed-loop control of the microwave power module based on the temperature data from the sensing and monitoring module and the return loss data detected by the microwave power module, so as to execute a custom temperature curve.

2. The microwave heating controllable power source according to claim 1, characterized in that, The microwave power module includes: The microwave generator module consists of a magnetron and a frequency stabilization circuit. The microwave modulation module, designed based on the injection-locking principle, includes a voltage-controlled oscillator (VCO) for receiving signals from the central control module to adjust the frequency and amplitude of the output microwave. The return loss detection module includes a directional coupler and a power detection module, which are used to measure the return loss value (S11 parameter) and its corresponding operating frequency and report it to the central control module.

3. The microwave heating controllable power source according to claim 2, characterized in that, The central control module is further configured to: calculate the dielectric constant and loss tangent of the material based on the S11 parameters and operating frequency reported by the return loss detection module, and adjust the output target of microwave power and frequency based on the changes in the dielectric constant and loss tangent.

4. The microwave heating controllable power source according to claim 1, characterized in that, The sensing and monitoring module includes a temperature sensor with a temperature measurement accuracy of no more than ±4℃ and a sampling frequency of no less than 1 time / second; and the central control module is further configured to dynamically adjust the microwave power through a PID algorithm so that the material temperature rise rate is controllable within the range of 0-20℃ / min during the heating stage, and to maintain the temperature error during the constant temperature stage not exceeding ±4℃.

5. The microwave heating controllable power source according to claim 1, characterized in that, The central control module is further configured to automatically adjust the microwave output to balance the radiation intensity when a temperature difference between different areas exceeds 10°C.

6. The microwave heating controllable power source according to claim 1, characterized in that, The auxiliary support module includes a microwave leakage detector and a metal shielding shell; the central control module is further configured to immediately cut off the power supply to the microwave power module when the detected microwave leakage exceeds 0.4W / m².

7. The microwave heating controllable power source according to claim 1, characterized in that, The auxiliary support module includes a backup power supply; the central control module is further configured to automatically save the current process data and unfinished temperature curve parameters using the backup power supply in the event of a sudden power outage.

8. A microwave heating method using a microwave heating controllable power source as described in claim 1, characterized in that, Includes the following steps: S1: Parameter preset, input process parameters including multiple custom temperature profiles; S2: Heating control, based on real-time monitoring of material temperature, dynamically adjusts microwave power through closed-loop control to make the temperature follow a preset curve; at the same time, the dielectric properties of the material are inverted based on real-time monitoring of microwave return loss data, and the control parameters are adjusted accordingly. S3: Anomaly handling, including temperature anomaly handling, microwave leakage and pressure anomaly handling, and sudden power outage and data protection handling.

9. The method according to claim 8, characterized in that, Step S2 is further configured as follows: The dielectric constant and loss tangent of the material are calculated by inversion based on the return loss value (S11) and the operating frequency. Based on the changes in dielectric constant and loss tangent, switch the pre-stored PID parameter group or update the target settings for microwave power and frequency.

10. The method according to claim 8, characterized in that, The abnormal temperature handling in step S3 includes: if the material temperature exceeds 300°C, immediately reduce the microwave power to zero and forcefully dissipate heat; if it does not return to the safe range within 1 minute, cut off the microwave power supply.

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