Microwave on-line moisture detection device and method for temperature and humidity control drying equipment

Abstract

The application provides a microwave online moisture detection device and method of a temperature and humidity control drying equipment, which comprises a temperature and humidity control drying equipment, a microwave online moisture detection system, a range finder device and a central control system, the microwave system is provided with an antenna guide rail platform capable of realizing XYZ three-axis movement and a symmetrical reference measurement microwave antenna, and the range finder is provided with a multilayer heat insulation protection structure; the method receives material signals through the microwave antenna, combines thickness measurement of the range finder and environment humidity detection of the reference antenna, calculates real moisture values through a thickness-humidity double compensation algorithm of linear interpolation or polynomial fitting, and finally displays and stores data by the central control system. The application realizes real-time, nondestructive and continuous detection of material moisture, has multi-point scanning capacity, is suitable for high-temperature drying conditions, greatly improves detection precision, and provides technical support for quality control and energy saving and consumption reduction of drying processes in the fields of pharmacy, food and the like.

Description

Technical Field

[0001] This invention relates to the field of online detection technology in the drying process, and in particular to a microwave online moisture detection device and method for temperature and humidity controlled drying equipment. Background Technology

[0002] Temperature and humidity controlled drying equipment has wide applications in the drying of materials such as traditional Chinese medicine pills, extracts, and food. It provides a stable and uniform temperature and humidity environment, making it an important tool for drying kinetics research, process optimization, and quality control. However, existing drying equipment generally lacks online moisture detection methods, often relying on offline sampling and weighing methods to determine moisture content. This leads to problems such as data lag, damage to the drying environment, and an inability to reflect the true drying process.

[0003] A few devices have attempted to incorporate weight sensors for moisture monitoring, such as the patent with publication number CN119620813A. However, these devices are susceptible to interference from factors such as mechanical vibration and temperature drift, resulting in poor measurement stability and difficulty in long-term reliable operation in complex drying environments. Furthermore, existing microwave moisture detection devices, when used, do not adequately consider the impact of material thickness variations and environmental humidity interference on microwave signals, leading to limited measurement accuracy. Moreover, most measurements are single-point measurements, failing to reflect the overall moisture distribution of the material. Therefore, there is an urgent need for a highly integrated, interference-resistant, multi-point measurement-capable microwave online moisture detection device with density and environmental compensation functions. Summary of the Invention

[0004] The purpose of this invention is to provide a microwave online moisture detection device and method for temperature and humidity controlled drying equipment. The aim is to develop a microwave online moisture detection device and method for temperature and humidity controlled drying equipment that combines thickness and environmental humidity compensation, multi-point scanning measurement and high temperature protection capabilities. This solves the industry pain points of existing online moisture detection in drying equipment, such as limited accuracy, poor anti-interference, and inability to reflect the overall moisture distribution of materials, and achieves real-time, non-destructive, continuous and accurate detection of material moisture during the drying process.

[0005] According to one objective of the present invention, a microwave online moisture detection device for a temperature and humidity controlled drying equipment is provided, comprising a temperature and humidity controlled drying equipment, a microwave online moisture detection system, a rangefinder device, and a central control system. The microwave online moisture detection system includes a microwave transmitting antenna, a microwave receiving antenna, a microwave transmitter, a microwave receiver, a signal processing unit, a reference measurement microwave antenna, and a microwave antenna moving guide rail platform. The microwave transmitting antenna and the microwave receiving antenna are connected to the microwave transmitter and the microwave receiver, respectively. The microwave antenna moving guide rail platform is disposed within the temperature and humidity controlled drying equipment. The rangefinder device is fixedly connected to the microwave antenna moving guide rail platform and is used to measure the material thickness in real time and transmit the thickness signal to the signal processing unit. The reference measurement microwave antenna is disposed within the temperature and humidity controlled drying equipment and is used to detect the ambient humidity and provide humidity compensation for moisture measurement. The signal processing unit can calculate the true moisture value of the material according to a thickness and humidity compensation algorithm. The central control system is communicatively connected to the signal processing unit and is used to receive, display, and store moisture data.

[0006] Furthermore, the microwave antenna moving guide rail platform includes a horizontal guide rail, a vertical guide rail, a support frame, a connecting rod I, a permanent magnet motor, and a drying tray. The permanent magnet motor drives the microwave antenna moving guide rail platform to move the microwave transmitting antenna and the microwave receiving antenna in the XYZ axis directions. The microwave antenna moving guide rail platform can realize single-point scanning, multi-point scanning, or gridded scanning measurement modes.

[0007] Furthermore, the reference measurement microwave antenna is symmetrically installed on the inner wall of the temperature and humidity control drying equipment. The reference measurement microwave antenna works synchronously with the microwave transmitting antenna and the microwave receiving antenna, and the detection frequencies of the three are consistent.

[0008] Furthermore, the rangefinder device includes a microwave radar rangefinder, a connecting rod II, a telescopic rod, and a multi-layer heat-insulating protective shell. The microwave radar rangefinder is a non-contact rangefinder sensor, which is fixed inside the multi-layer heat-insulating protective shell by the connecting rod II. The multi-layer heat-insulating protective shell consists of a stainless steel protective shell, a heat insulation layer, and an aluminum protective inner shell from the outside to the inside. The aluminum protective inner shell is provided with optical quartz glass at the detection end of the microwave radar rangefinder.

[0009] Furthermore, the drying tray is made of polypropylene plastic, the drying tray is placed on a fixed support frame, and the drying tray is located on the detection path between the microwave transmitting antenna and the microwave receiving antenna.

[0010] Furthermore, the microwave transmitting antenna and the microwave receiving antenna are symmetrically fixed on the transverse guide rail by the connecting rod I, and the microwave transmitting antenna and the microwave receiving antenna are connected to the microwave transmitter and the microwave receiver, which are placed outside the temperature and humidity control drying equipment, by means of a high-temperature resistant extended shielded cable.

[0011] Furthermore, the permanent magnet motor is connected to the support frame via a transmission.

[0012] Furthermore, the central control system includes a human-machine interface, a data storage module, and a communication interface. The central control system can automatically trigger microwave moisture detection and material thickness measurement according to a preset time interval, and can be linked with the temperature and humidity control module of the temperature and humidity control drying equipment.

[0013] A microwave online moisture detection method based on the above-mentioned device includes the following steps: S1: Place the material in the drying tray. The microwave transmitter drives the microwave transmitting antenna to transmit microwave signals. The microwave receiving antenna receives the microwave signals passing through the material and transmits them to the microwave receiver. The microwave receiver feeds the signals back to the signal processing unit. S2: The distance measuring device measures the thickness of the material in the drying tray in real time and transmits the thickness signal to the signal processing unit; S3: The reference measurement microwave antenna synchronously detects the ambient humidity inside the temperature and humidity control drying equipment and transmits the humidity signal to the signal processing unit. S4: The signal processing unit calls the thickness and humidity compensation algorithm, and calculates the true moisture value of the material by combining the thickness-moisture and humidity-moisture relationship curves established by the calibration experiment. The compensation algorithm is a linear interpolation model or a polynomial fitting model. S5: The signal processing unit transmits the actual moisture value to the central control system, where the moisture data is displayed through the human-machine interface and stored through the data storage module.

[0014] Furthermore, the microwave transmitting antenna and the microwave receiving antenna transmit and receive microwave signals to the material in single-point scanning, multi-point scanning, or grid scanning modes via a microwave antenna moving guide platform; in step S2, the rangefinder device is linked with the microwave transmitting antenna and the microwave receiving antenna, and synchronously measures the material thickness at the corresponding position as the antenna moves; in step S5, the central control system links the stored moisture data with the temperature and humidity control module of the temperature and humidity control drying equipment, and uses changes in moisture data to help determine the drying endpoint of the material, thereby realizing intelligent control of the drying process.

[0015] The technical solution of this invention effectively solves the pain points of existing drying equipment, such as low accuracy of online moisture detection, poor anti-interference, and inability to reflect the overall moisture distribution of materials. It achieves real-time, non-destructive, and continuous monitoring of material moisture during the drying process without opening the drying chamber door, thus avoiding damage to the drying environment. Through a dual compensation mechanism for thickness and ambient humidity, the accuracy of microwave measurement is significantly improved, eliminating signal interference caused by changes in material thickness and ambient humidity. Multi-dimensional scanning of the microwave antenna enables assessment of the overall moisture distribution of the material, and the high-temperature resistant protective structure of the rangefinder is suitable for high-temperature drying conditions. Simultaneously, the intelligent integrated control of the equipment can be linked with the drying control module to assist in determining the drying endpoint, effectively shortening the drying cycle, reducing energy consumption, and improving product qualification rate. It is applicable to quality control of the drying process in multiple fields such as pharmaceuticals, food, and agricultural products. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of the device according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the microwave antenna moving guide rail platform according to an embodiment of the present invention; Figure 3 This is a schematic diagram of a rangefinder device according to an embodiment of the present invention; Figure 4 This is a flowchart of the microwave online moisture detection process according to an embodiment of the present invention.

[0018] In the diagram: 1. Temperature and humidity controlled drying equipment; 201. Microwave transmitting antenna; 202. Microwave receiving antenna; 203. Microwave transmitter; 204. Microwave receiver; 205. Signal processing unit; 206. High-temperature resistant extended shielded cable; 207. Reference measurement microwave antenna; 208. Microwave antenna moving guide rail platform; 209. Horizontal guide rail; 210. Vertical guide rail; 211. Support frame; 212. Connecting rod I; 213. Permanent magnet motor; 214. Drying tray; 215. Fixed support frame; 3. Rangefinder device; 301. Microwave radar rangefinder; 302. Connecting rod II; 303. Telescopic rod; 304. Stainless steel protective shell; 305. Heat insulation layer; 306. Aluminum protective inner shell; 307. Optical quartz glass; 4. Central control panel; 401 Human-machine interface; 402 Data storage module; 403 Communication interface. Detailed Implementation

[0019] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. 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.

[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] Example 1 like Figures 1-4 As shown, a microwave online moisture detection device for a temperature and humidity controlled drying equipment includes a temperature and humidity controlled drying equipment 1, a microwave online moisture detection system, a rangefinder device 3, and a central control system 4; wherein: The microwave online moisture detection system includes a microwave transmitting antenna 201, a microwave receiving antenna 202, a microwave transmitter 203, a microwave receiver 204, a signal processing unit 205, a reference measurement microwave antenna 207, and a microwave antenna moving guide rail platform 208. The microwave transmitting antenna 201 and the microwave receiving antenna 202 are connected to the microwave transmitter 203 and the microwave receiver 204 via a high-temperature resistant extended shielded cable 206.

[0023] The reference measurement microwave antenna 207 is symmetrically mounted on the inner wall of the drying equipment to detect ambient humidity. The signal processing unit 205 compensates for the moisture measurement results based on the humidity value. The reference measurement microwave antenna 207 operates synchronously with the main measurement antenna, and the detection frequency is the same.

[0024] The microwave antenna moving guide platform 208 can realize single-point scanning, multi-point scanning, or gridded scanning modes. Specifically, the microwave antenna moving guide platform 208 includes a horizontal guide rail 209, a vertical guide rail 210, a support frame 211, a connecting rod I 212, a permanent magnet motor 213, a drying tray 214, and a fixed support frame 215, realizing the movement of the microwave transmitting antenna 201 and the microwave receiving antenna 202 in the XYZ axis directions. The drying tray 214 is made of polypropylene plastic and is placed on the fixed support frame 215.

[0025] The microwave antenna moving guide rail platform 208 is placed in the temperature and humidity control drying equipment 1; the polypropylene plastic drying tray 214 is placed between the microwave transmitting antenna 201 and the microwave receiving antenna 202, and is supported by the fixed support frame 215 on the inner wall of the temperature and humidity control drying equipment 1. The permanent magnet motor 213 is connected to the support frame 211 and placed between the inner and outer chambers of the temperature and humidity control drying equipment 1; The microwave transmitting antenna 201 and the microwave receiving antenna 202 are symmetrically connected and fixed on the horizontal guide rail 209 by the connecting rod I 212; the microwave transmitting antenna 201 and the microwave receiving antenna 202 are connected to the microwave transmitter 203 and the microwave receiver 204 placed outside the temperature and humidity control drying equipment 1 by a high temperature resistant extended cable; the reference measurement microwave antenna 207 is symmetrically installed on the left and right inner walls of the temperature and humidity control drying equipment 1.

[0026] The rangefinder device 3 includes a microwave radar rangefinder 301, a connecting rod II 302, a telescopic rod 303, and a multi-layer heat-insulating protective shell. The multi-layer heat-insulating protective shell includes a stainless steel protective shell 304, a heat insulation layer 305, an aluminum protective inner shell 306, and an optical quartz glass 307, forming a multi-layer heat-insulating protective structure. The microwave radar rangefinder 301 is fixedly connected to the aluminum protective inner shell 306 via the connecting rod II 302. The stainless steel protective shell 304, the heat insulation layer 305, and the aluminum protective inner shell 306 serve to isolate external heat conduction and protect the microwave radar rangefinder 301 from high temperatures. The optical quartz glass 307 is positioned directly below the microwave radar rangefinder 301.

[0027] The microwave radar rangefinder 301 is a non-contact ranging sensor suitable for high-temperature and high-humidity environments. The rangefinder device 3 is fixedly connected to the transverse guide rail 209 via a telescopic rod 303, measuring the material thickness in real time and transmitting the thickness signal to the signal processing unit 205. The signal processing unit 205 has a built-in "thickness-moisture" compensation curve, automatically correcting the moisture measurement value based on the material thickness.

[0028] The central control system 4 is connected to the human-machine interface 401, the data storage module 402, and the communication interface 403. The central control system 4 automatically triggers microwave moisture detection and thickness measurement according to a set time interval. The signal processing unit 205 transmits the compensated moisture value to the human-machine interface 401 for display, and the data storage module 402 automatically records it. The central control system 4 is installed on the front of the main body of the temperature and humidity control equipment.

[0029] When using the device of the present invention, the material is initially placed in the temperature and humidity controlled drying equipment 1 for drying. The microwave moisture detection system is started. According to the time detection interval output by the central control system 4, the microwave transmitter 203 sends a continuous and stable microwave signal to the microwave transmitting antenna 201. After receiving the signal, the microwave transmitting antenna 201 acts on the material. The corresponding microwave receiving antenna 202 receives the signal acting on the material and inputs it into the microwave receiver 204. Then, the microwave receiver 204 feeds back the received microwave signal to the microwave signal processing unit 205. The signal processing unit 205 calculates the moisture content in real time. Meanwhile, the reference measurement microwave antenna 207 begins to transmit and receive signals, its function being to detect the humidity value in the environment, thereby eliminating interference caused by environmental humidity. The transverse guide rail 209 connected to the microwave transmitting antenna 201 is connected to the rangefinder device 3 via the telescopic rod 303. The rangefinder device 3 contains a microwave radar rangefinder 301, whose function is to measure the thickness of the material. Because the thickness of the material changes during the drying process, it will cause errors in the microwave moisture detection signal. The microwave radar rangefinder 301 measures the accurate thickness of the material in real time. The central control system 4 and the signal processing unit 205 receive the thickness value and the original moisture value, respectively. The signal processing unit 205 automatically subtracts the moisture value according to the preset "thickness-moisture" compensation curve, inputs the final true moisture signal, and transmits the data to the human-machine interface 401 for display. The data storage module 402 automatically records the moisture data.

[0030] In this embodiment of the invention, multiple measurements can be performed on materials from different locations at the same time, making the overall moisture content measurement of the material more accurate. The microwave transmitting antenna 201 and microwave receiving antenna 202 are connected to the transverse guide rail 209 via connecting rod I 212, allowing the microwave antenna to move along the XYZ axes of the microwave antenna moving guide rail platform 208. This enables the measurement of the overall moisture content of the material within a shorter time interval, resulting in more accurate moisture measurement results and, to some extent, reflecting the uniformity of the material during the drying process.

[0031] A microwave online moisture detection method based on the above-mentioned device includes the following steps: S1: The material is placed in the drying tray 214, the microwave transmitting antenna 201 transmits microwave signals, and the microwave receiving antenna 202 receives signals passing through the material. S2: The distance measuring device 3 measures the material thickness in real time; S3: Reference measurement microwave antenna 207 detects ambient humidity; S4: The signal processing unit 205 calculates the actual moisture value according to the thickness and humidity compensation algorithm; S5: The central control system 4 displays and stores moisture data.

[0032] In step S4, the compensation algorithm is a linear interpolation or polynomial fitting model, based on the thickness-moisture and humidity-moisture relationship curves established by the calibration experiment.

[0033] like Figure 4 As shown, the core logic of the microwave online moisture detection process of this invention is as follows: Acquiring Measurement Signals: The microwave signal (total attenuation A) passing through the material is acquired via the measurement channel. total This corresponds to step S1 (receiving a signal passing through the material).

[0034] Acquiring the reference signal: The ambient background signal (background attenuation value A) is acquired through the reference channel. air This corresponds to step S3 (the reference antenna detects the ambient humidity for environmental compensation).

[0035] Environmental compensation: A is calculated through differential calculation. material =A total -A air This eliminates the interference of environmental factors (humidity) on the measurement, which corresponds to the core purpose of "humidity compensation".

[0036] Thickness compensation: The laser thickness signal (corresponding to the thickness measured by the rangefinder in step S2) is introduced as the input parameter of the moisture calculation model.

[0037] Moisture content calculation: combined with the compensated attenuation value A materialThe thickness signal is used to obtain the final moisture value through the moisture calculation model (corresponding to the "thickness-moisture, humidity-moisture relationship curve" compensation algorithm in step S4).

[0038] Output result: Display and storage of the final moisture content value, corresponding to step S5.

[0039] This invention has the following key technical features: Thickness compensation mechanism: The rangefinder device 3 is linked with the microwave transmitting antenna 201 to measure the material thickness in real time, and the signal processing unit 205 automatically corrects the moisture value according to the preset "thickness-moisture" compensation curve; Environmental humidity compensation mechanism: A reference measurement microwave antenna 207 is set up to synchronously detect the environmental humidity inside the drying chamber and eliminate its interference with the microwave moisture signal; Multi-point scanning measurement mechanism: The microwave antenna moves along the XYZ three axes via the microwave antenna moving guide platform 208, which can complete the measurement of the overall moisture distribution of the material in a short time; High-temperature protection structure: The rangefinder device 3 adopts a multi-layer protection structure including a stainless steel outer shell, a heat insulation layer, an aluminum inner shell, and optical quartz glass, making it suitable for high-temperature and dry environments.

[0040] In summary, this invention deeply integrates microwave online moisture detection technology into temperature and humidity controlled drying equipment, constructing an integrated online moisture detection system with thickness compensation, environmental humidity compensation, multi-point scanning measurement, and high-temperature protection capabilities. Compared with existing technologies, it has the following significant advantages: This invention enables real-time, non-destructive, and continuous moisture monitoring during the drying process. Overcoming the limitations of offline sampling: It eliminates the need to open the drying chamber door, avoiding disruption of the internal temperature and humidity environment and the continuity of the drying process, and can truly reflect the dynamic process of moisture change in materials throughout the entire drying cycle.

[0041] Alternative weight sensor solution: Overcomes the shortcomings of the weighing method, which is susceptible to interference from mechanical vibration, temperature drift, non-moisture weight loss, etc., and is suitable for industrial drying environments with severe vibration and large temperature and humidity fluctuations.

[0042] This invention provides thickness-adaptive density compensation, significantly improving microwave measurement accuracy. The thickness change of the material during the drying process is measured in real time using a microwave radar rangefinder. The signal processing unit then processes the data based on a preset thickness value. The "moisture" compensation curve automatically corrects microwave phase shift errors.

[0043] It effectively eliminates the problem of microwave signal phase ambiguity caused by uneven material shrinkage, expansion, and accumulation, making the moisture measurement results closer to the true value.

[0044] This invention provides environmental humidity reference compensation to eliminate interference from intracavity humidity. A symmetrically arranged reference measurement microwave antenna works synchronously with the main measurement channel to detect the ambient humidity inside the drying chamber in real time.

[0045] The signal processing unit dynamically subtracts moisture measurements based on the humidity signal, avoiding the superimposed effect of water vapor on microwave absorption and significantly improving detection accuracy in low moisture and high humidity environments.

[0046] This invention enables omnidirectional mobile scanning to assess the overall moisture distribution of materials. The microwave antenna can move freely in the XYZ three-axis direction via the guide rail platform, and can complete the scanning measurement of multiple points or gridded areas in the drying tray in a short time.

[0047] It not only obtains the overall average moisture content, but also generates a moisture distribution heat map, which intuitively reflects the uniformity of material drying and provides visual data support for process optimization (such as airflow organization and temperature field adjustment).

[0048] This invention features a high-temperature resistant protective design, adaptable to harsh, dry working conditions. The rangefinder device adopts a multi-layer heat insulation and protection structure consisting of a stainless steel outer shell, a heat insulation layer, an aluminum protective inner shell, and an optical quartz glass window, which effectively isolates high temperature conduction and radiation.

[0049] Ensuring the long-term stable operation of the microwave radar rangefinder in environments with temperatures ranging from 60℃ to 120℃ or even higher expands the applicability of microwave online detection technology in high-temperature drying scenarios such as traditional Chinese medicine, food, and chemicals.

[0050] This invention features intelligent integration and control, enhancing the level of automation. The central control system can automatically trigger detection and record data according to preset time intervals, and link with the temperature and humidity control module of the drying equipment.

[0051] Real-time moisture data can help intelligently determine the drying endpoint, prevent over-drying or dry exterior with wet interior, thereby shortening the drying cycle, reducing energy consumption, and improving product qualification rate.

[0052] In summary, this invention fundamentally solves the industry pain point of existing temperature and humidity control drying equipment lacking accurate online moisture detection methods. It also has four core advantages: high precision, strong anti-interference, full-view measurement, and environmental resistance. It provides an innovative technical path for quality control and energy saving in the drying process of pharmaceutical, food, and agricultural products.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A microwave online moisture detection device for temperature and humidity controlled drying equipment, characterized in that, The system includes a temperature and humidity controlled drying device, a microwave online moisture detection system, a rangefinder device, and a central control system. The microwave online moisture detection system comprises a microwave transmitting antenna, a microwave receiving antenna, a microwave transmitter, a microwave receiver, a signal processing unit, a reference measurement microwave antenna, and a microwave antenna moving guide rail platform. The microwave transmitting antenna and the microwave receiving antenna are connected to the microwave transmitter and the microwave receiver, respectively. The microwave antenna moving guide rail platform is located within the temperature and humidity controlled drying device. The rangefinder device is fixedly connected to the microwave antenna moving guide rail platform and is used to measure the material thickness in real time and transmit the thickness signal to the signal processing unit. The reference measurement microwave antenna is located within the temperature and humidity controlled drying device and is used to detect ambient humidity and provide humidity compensation for moisture measurement. The signal processing unit can calculate the true moisture value of the material based on a thickness and humidity compensation algorithm. The central control system is communicatively connected to the signal processing unit and is used to receive, display, and store moisture data.

2. The microwave online moisture detection device for temperature and humidity controlled drying equipment according to claim 1, characterized in that, The microwave antenna moving guide platform includes a horizontal guide rail, a vertical guide rail, a support frame, a connecting rod I, a permanent magnet motor, and a drying tray. The permanent magnet motor drives the microwave antenna moving guide platform to move the microwave transmitting antenna and the microwave receiving antenna in the XYZ axis directions. The microwave antenna moving guide platform can realize single-point scanning, multi-point scanning, or gridded scanning measurement modes.

3. The microwave online moisture detection device for temperature and humidity controlled drying equipment according to claim 1, characterized in that, The reference measurement microwave antenna is symmetrically installed on the inner wall of the temperature and humidity control drying equipment. The reference measurement microwave antenna works synchronously with the microwave transmitting antenna and the microwave receiving antenna, and the detection frequencies of the three are consistent.

4. The microwave online moisture detection device for temperature and humidity controlled drying equipment according to claim 1, characterized in that, The rangefinder device includes a microwave radar rangefinder, a connecting rod II, a telescopic rod, and a multi-layer heat-insulating protective shell. The microwave radar rangefinder is a non-contact rangefinder sensor, which is fixed inside the multi-layer heat-insulating protective shell by the connecting rod II. The multi-layer heat-insulating protective shell consists of a stainless steel protective shell, a heat insulation layer, and an aluminum protective inner shell from the outside to the inside. The aluminum protective inner shell is provided with optical quartz glass at the detection end of the microwave radar rangefinder.

5. The microwave online moisture detection device for temperature and humidity controlled drying equipment according to claim 2, characterized in that, The drying tray is made of polypropylene plastic and is placed on a fixed support frame. The drying tray is located on the detection path between the microwave transmitting antenna and the microwave receiving antenna.

6. The microwave online moisture detection device for temperature and humidity controlled drying equipment according to claim 2, characterized in that, The microwave transmitting antenna and the microwave receiving antenna are symmetrically fixed on the horizontal guide rail by the connecting rod I. The microwave transmitting antenna and the microwave receiving antenna are connected to the microwave transmitter and the microwave receiver, which are placed outside the temperature and humidity control drying equipment, by a high-temperature resistant extended shielded cable.

7. The microwave online moisture detection device for temperature and humidity controlled drying equipment according to claim 2, characterized in that, The permanent magnet motor is connected to the support frame via a transmission.

8. The microwave online moisture detection device for temperature and humidity controlled drying equipment according to claim 1, characterized in that, The central control system includes a human-machine interface, a data storage module, and a communication interface. The central control system can automatically trigger microwave moisture detection and material thickness measurement according to a preset time interval, and can be linked with the temperature and humidity control module of the temperature and humidity control drying equipment.

9. A microwave online moisture detection method based on the device according to any one of claims 1-8, characterized in that, Includes the following steps: S1: Place the material in the drying tray. The microwave transmitter drives the microwave transmitting antenna to transmit microwave signals. The microwave receiving antenna receives the microwave signals passing through the material and transmits them to the microwave receiver. The microwave receiver feeds the signals back to the signal processing unit. S2: The distance measuring device measures the thickness of the material in the drying tray in real time and transmits the thickness signal to the signal processing unit; S3: The reference measurement microwave antenna synchronously detects the ambient humidity inside the temperature and humidity control drying equipment and transmits the humidity signal to the signal processing unit. S4: The signal processing unit calls the thickness and humidity compensation algorithm, and calculates the true moisture value of the material by combining the thickness-moisture and humidity-moisture relationship curves established by the calibration experiment. The compensation algorithm is a linear interpolation model or a polynomial fitting model. S5: The signal processing unit transmits the actual moisture value to the central control system, where the moisture data is displayed through the human-machine interface and stored through the data storage module.

10. The microwave online moisture detection method according to claim 9, characterized in that, In step S1, the microwave transmitting antenna and the microwave receiving antenna transmit and receive microwave signals to the material in single-point scanning, multi-point scanning, or grid scanning modes via the microwave antenna moving guide platform. In step S2, the rangefinder device is linked with the microwave transmitting antenna and the microwave receiving antenna, and synchronously measures the material thickness at the corresponding position as the antenna moves. In step S5, the central control system links the stored moisture data with the temperature and humidity control module of the temperature and humidity control drying equipment, and uses changes in moisture data to help determine the drying endpoint of the material, thereby realizing intelligent control of the drying process.

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