LWC hot wire moisture meter

Abstract

The utility model discloses LWC hot line moisture content tester relates to moisture content test field, including equipment shell, hangs the interface, core function component and external interaction module, the core function component is integrated in the equipment inside, and external interaction module is adapted to install with equipment shell. The utility model discloses the integrated structure of miniature temperature sensor and hot line induction sheet, can gather induction sheet surface temperature data in real time and synchronously transmission to the processing module, through with the measured temperature value substitution liquid water content inversion formula, effectively eliminated the error of estimated temperature introduction, make the measurement precision greatly promote, provide the key technical support for the accurate detection under the complex meteorological condition, three segment type hot line induction sheet adopts aba sandwich structure when detecting that the air current speed is lower than the safety threshold value, and the system automatically cuts off the heating power supply, avoids hot line induction sheet to continue heating under static environment, effectively avoided the structure fatigue caused by invalid heating.

Description

Technical Field

[0001] This utility model belongs to the field of moisture content testing technology, specifically, it relates to the LWC hot wire moisture content tester. Background Technology

[0002] Currently, my country relies solely on imports for its airborne hot-wire moisture content sensors, resulting in high equipment procurement costs and unstable supply cycles, severely hindering the independent development of my country's airborne meteorological detection industry. Foreign manufacturers have established a monopoly on core technologies, manufacturing processes, and the supply chain, limiting domestic research and applications in related fields due to technological barriers. This makes it difficult to optimize for my country's complex meteorological conditions, significantly impacting the refined implementation of key operations such as weather modification and low-altitude meteorological detection.

[0003] During use, existing equipment often suffers from issues where the hot-wire sensor remains heated even when there is no airflow, due to airflow monitoring failure or control logic defects. This abnormal heating rapidly leads to aging, performance degradation, and even burnout of the sensor material, significantly increasing the frequency of consumable replacements. This not only raises maintenance costs but may also disrupt the continuous acquisition of meteorological data during flight due to sudden malfunctions, posing a threat to aviation safety and the reliability of meteorological detection.

[0004] Existing de-icing heating systems employ a fixed-cycle heating mode, lacking a linkage mechanism with aircraft flight status (such as takeoff, cruise, and landing) and meteorological environmental parameters (such as temperature and icing risk level). Ineffective heating of the equipment when it is parked on the ground or in low-icing-risk scenarios not only wastes energy but also causes sensor structural fatigue due to frequent thermal expansion and contraction, significantly shortening the overall service life of the equipment and increasing the full-cycle maintenance costs of aviation equipment. Therefore, this utility model is proposed. Utility Model Content

[0005] To solve the above-mentioned technical problems, the basic concept of the technical solution adopted by this utility model is as follows: The LWC hotline moisture content tester includes a device housing, mounting interface, core functional components, and an external interaction module; the core functional components are integrated inside the device, and the external interaction module is adapted to the device housing. The core functional components include a three-section hot-wire induction element, a high-response temperature-sensing resistor, a constant internal resistance closed-loop power control system, and a data acquisition-control-algorithm fusion processing system; the external interaction module includes a power conversion unit, a signal interface unit, and a de-icing heating system. The three-segment hot-wire induction element is coupled to a high-response temperature-sensing resistor. The high-response temperature-sensing resistor is used to collect the actual temperature of the three-segment hot-wire induction element in real time, providing temperature correction data for data processing. The constant internal resistance closed-loop power control system is electrically connected to the three-segment hot-wire induction element and is used to control the power supply of the three-segment hot-wire induction element to prevent it from being damaged by static dry burning. The data acquisition-control-algorithm fusion processing system is connected to the high response value temperature measuring resistor, the constant internal resistance closed-loop power control system, the de-icing heating system and the external aircraft system. It can receive the airspeed and status information transmitted by the aircraft through the bus and control the power supply start and stop of the three-section hot wire induction plate and the working status of the de-icing heating system in a coordinated manner. The power conversion unit is used to convert the external aircraft 28V power supply into the 5V and 3.3V voltage required by the equipment; the signal interface unit supports the CAN / RS232 protocol to realize data interaction between the equipment and external systems; the de-icing heating system is mounted inside the equipment shell for de-icing operations.

[0006] Preferably, the three-segment hot wire induction element adopts an ABA sandwich structure, wherein: layer A is a 1R alloy winding, with two sets, the two sets of layer A located at both ends of layer B, the main function of which is to assist in heating and to make the heat at both ends of layer B and the central area uniform through heat conduction; layer B is a 2R alloy winding, which serves as the liquid water detection end for heat exchange with high-altitude cloud water; the high-response temperature measuring resistor is arranged inside the winding of layer B and outputs a corresponding voltage signal as the temperature of layer B changes.

[0007] Preferably, the resistance values ​​of the A-layer 1R alloy winding and the B-layer 2R alloy winding are both directly proportional to their own temperature; after the two A-layer 1R alloy windings are connected in series, they are also electrically connected to an independent constant internal resistance closed-loop power control system, and the control logic of the system for the A-layer is consistent with the control logic for the B-layer.

[0008] Preferably, the constant internal resistance closed-loop power control system consists of an operational amplifier AD8638B, a power controller, and a 1R high-power reference resistor (R5). The B-layer winding of the three-segment hot-wire induction element is equivalent to a resistor R4 in the circuit, and R4 and R5 are connected in series to form a loop. Pin 5 of the operational amplifier AD8638B is connected to a reference voltage, and pin 6 is connected to the voltage divider signal of R4 and R5. The operational amplifier compares the voltage difference between pin 5 and pin 6 and outputs an adjustment signal to the power controller, thereby adjusting the output power of the power controller. The system also includes a voltage divider circuit composed of resistors R1, R2, and R3. When the output value of the voltage divider circuit is consistent with the voltage divider value of R4 and R5, the circuit enters a balanced state, at which time the temperature of the B-layer winding is stabilized at around 120°C. The adjustment process of the constant internal resistance closed-loop power control system is completed in microseconds (μs), which can avoid the dry burning damage of the three-segment hot-wire induction element caused by adjustment shock.

[0009] Preferably, the data acquisition-control-algorithm fusion processing system is based on an STM32F103C8T6 microcontroller and equipped with a 16-bit high-speed ADC chip. The 16-bit high-speed ADC chip communicates with the STM32F103C8T6 microcontroller via an SPI bus to acquire the voltage signal of the B-layer winding of the three-segment hot-wire induction element and the voltage signal of the high-response temperature-sensing resistor. The STM32F103C8T6 microcontroller receives aircraft airspeed and status information via a CAN bus interface, calculates the relative power loss and actual temperature of the three-segment hot-wire induction element based on the acquired voltage signals, and outputs control signals in conjunction with the aircraft status information: on the one hand, it controls the power supply switch of the three-segment hot-wire induction element to be turned on and off, and on the other hand, it controls the power MOSFET to start or stop the de-icing heating system.

[0010] Preferably, the de-icing heating system is a flexible heating film structure, which is attached to the inner wall of the equipment housing; the start-up logic of the de-icing heating system is linked to the aircraft status: when the STM32F103C8T6 microcontroller determines through the CAN bus that the aircraft is in a non-static operating condition, it controls the power MOSFET to conduct and supply power to the de-icing heating system; if it determines that the aircraft is in a static operating condition, it cuts off the power supply to the de-icing heating system to avoid static heating from reducing the service life of the equipment.

[0011] Compared with the prior art, the present invention has the following advantages: This invention integrates a miniature temperature sensor with a hot-wire induction element, enabling real-time acquisition of surface temperature data and synchronous transmission to the processing module. By substituting the measured temperature value into the liquid water content inversion formula, the error introduced by temperature estimation is effectively eliminated, significantly improving measurement accuracy. This solves the measurement deviation problem caused by temperature parameter distortion in traditional sensors, providing key technical support for accurate detection under complex meteorological conditions. Regarding response speed, the constant internal resistance closed-loop system, based on the AD8638B operational amplifier, adjusts the power supply at the microsecond level by comparing the voltage divider signals of the hot-wire induction element and the reference resistor in real time, ensuring the thermal stability of the system. The wire temperature quickly stabilizes within the target range, avoiding the lengthy balancing process of staged heating and power adjustment required in existing devices. In terms of measurement accuracy, the three-segment hot wire induction element adopts an ABA sandwich structure: the A layers on both sides use auxiliary heating to ensure uniform temperature distribution in the B layer, avoiding detection deviations caused by local overheating or insufficient temperature; the high-response temperature sensing resistor embedded inside the B layer can synchronize the hot wire temperature in real time, forming a redundant verification with the temperature signal of the A layer resistor, further reducing the impact of temperature error on moisture content calculation. When the detected airflow velocity is lower than the safety threshold, the system automatically cuts off the heating power supply to prevent the hot wire induction element from continuously heating in a static environment.

[0012] This invention addresses the unique characteristics of airborne environments by employing state-linked de-icing, multi-protocol adaptation, and redundancy design. This significantly improves equipment reliability and scenario adaptability, overcoming the shortcomings of existing devices such as complex maintenance and weak adaptability. In de-icing control, the de-icing heating system does not operate continuously but is linked to the aircraft's airspeed via a data processing system: de-icing is only initiated when the aircraft is in dynamic conditions and the shell temperature is ≤5℃; heating is cut off under static conditions. This avoids ineffective energy consumption and prevents static heating from causing equipment aging, extending its service life. A heating control module that interacts in real time with aircraft status and meteorological data is constructed. By dynamically adjusting the de-icing heating power and cycle, the heating system achieves precise matching with flight conditions: it automatically enters energy-saving mode when parked on the ground, and intelligently starts and stops heating during flight according to the icing risk level, effectively avoiding structural fatigue caused by ineffective heating, and improving de-icing efficiency and flight safety under complex weather conditions. In addition, the system is equipped with multiple redundancies: the B-layer temperature is monitored by both high-response temperature measuring resistors and A-layer resistance signals, and the power regulation is verified by both voltage divider circuits and reference resistors, effectively avoiding measurement failures caused by single component failures, and greatly improving the reliability of the equipment in complex airborne environments.

[0013] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings. Attached Figure Description

[0014] In the attached diagram: Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0015] Figure 2 This is a schematic diagram of the system framework structure of this utility model.

[0016] Figure 3 This is a schematic diagram of the internal resistance closed-loop control structure of this utility model.

[0017] Figure 4 This is a schematic diagram of the circuit connection of this utility model.

[0018] In the diagram: 1. Equipment casing; 2. Mounting interface; 3. Hot wire sensor. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate this utility model.

[0020] like Figures 1 to 4 As shown, the LWC hot-wire moisture content tester has an overall rectangular structure. The outer casing 1 is made of aerospace-grade aluminum alloy with an anodized surface to improve corrosion resistance, making it suitable for standard airborne equipment installation spaces. A mounting interface 2 is provided on the side of the casing, using an M8 threaded connector structure, which can be directly fixed to the equipment bracket on the aircraft fuselage, ensuring no loosening or displacement during flight.

[0021] The equipment employs a layered internal layout: the upper layer integrates core functional components, including a three-section hot-wire induction element 3, a high-response temperature-sensing resistor, a constant internal resistance closed-loop power control system, and a data acquisition-control-algorithm fusion processing system; the lower layer houses external interaction modules, namely a power conversion unit, a signal interface unit, and a de-icing heating system. All components are fixed via a PCB board, with thermal insulation cotton placed between the PCB board and the inner wall of the casing to prevent interference from external ambient temperature on the internal circuitry. The three-section hot-wire induction element 3 is suspended at the front end of the casing by a metal bracket, with its sensing end (B-layer winding) extending 10mm beyond the casing to ensure full contact with high-altitude cloud water. The bracket surface is wrapped with a high-temperature resistant insulating layer to prevent conductivity between the induction element and the casing.

[0022] The three-section hot-wire induction element adopts an ABA sandwich structure. The A layer is a 1R alloy winding made of nickel-chromium alloy (Ni80Cr20). The resistance of a single A layer winding is 1Ω at room temperature. Two A layers are symmetrically arranged at both ends of the B layer, and each A layer winding has 50 turns. The B layer is a 2R alloy winding made of copper-nickel alloy (Cu55Ni45). The resistance of the B layer is 2Ω at room temperature, and the winding has 100 turns. It serves as the liquid water detection end, and its surface is polished to reduce the adhesion and residue of cloud water.

[0023] The high-response temperature sensing resistor is a platinum resistance thermometer (PT1000), which is adhered to the center of the B-layer winding using high-temperature adhesive and is completely embedded in the winding gap of the B-layer to ensure tight contact between the temperature sensing resistor and the B-layer winding, and to synchronize with the temperature changes of the B-layer in real time. The leads of the temperature sensing resistor are led out through the reserved holes in the B-layer winding and connected to the signal lines of the data acquisition system. The leads are wrapped with a polytetrafluoroethylene insulation layer to prevent short circuits with the winding.

[0024] Two sets of 1R alloy A-layer windings are connected in series and then connected to an independent constant internal resistance closed-loop power control system. After power-on, the heating power of the A-layer winding stabilizes at 0.5W, and the heat is transferred to both ends of the B-layer through thermal conduction. Since the contact area between the A-layer and B-layer is over 90%, and the heating power of the A-layer matches the heat loss of the B-layer, the temperature distribution uniformity error of the B-layer winding can be ensured to be ≤±2℃, avoiding measurement deviations caused by local temperature differences in the B-layer. At the same time, the resistance values ​​of both the A-layer and B-layer change proportionally with temperature (temperature coefficient is 0.00385 / ℃), and their resistance change signals can be used as a basis for auxiliary temperature monitoring, forming a redundant verification with the signal of the high-response temperature measuring resistor.

[0025] The constant internal resistance closed-loop power control system is based on the AD8638B operational amplifier and the DC-DC power controller (model LM25007). The specific circuit parameters are as follows: The 1R high-power reference resistor R5 is a metal film resistor with a rated power of 5W and a room temperature resistance of 1Ω, ensuring that it will not overheat and be damaged during long-term power supply. The voltage divider circuit consists of resistors R1 (10kΩ), R2 (20kΩ), and R3 (10kΩ), all of which are high-precision metal film resistors (accuracy ±0.1%). The output voltage of the voltage divider circuit (i.e., the reference voltage of pin 5 of the op-amp AD8638B) is set to 2.5V. The B-layer winding of the three-section hot-wire induction chip is equivalent to a resistor R4 in the circuit. It is connected in series with R5 to form the main circuit. The maximum current of the circuit is designed to be 2A to avoid excessive current that could burn out the winding.

[0026] After the device is powered on, the power controller outputs an initial voltage (12V). Current flows through resistors R4 (layer B winding) and R5. R4 heats up due to power-on, and its resistance increases with temperature. At this time, pin 6 of the AD8638B op-amp receives a voltage divider signal from R4 and R5 (the voltage increases with the resistance of R4), which is compared with the 2.5V reference voltage at pin 5. If the voltage at pin 6 is less than 2.5V, the op-amp outputs a high-level signal, which controls the power controller to increase the output power, increase the loop current, and cause the temperature of R4 to rise. If the voltage at pin 6 is greater than 2.5V, the op-amp outputs a low-level signal, which controls the power controller to reduce the output power, decrease the loop current, and lower the temperature of R4. When the output value of the voltage divider circuit (R1-R2-R3) is the same as the voltage divider value of R4 and R5 (both are 2.5V), the circuit enters a balanced state. At this time, the temperature of R4 is stable at 120℃±5℃, and the corresponding power supply is about 1.2W.

[0027] The response time of this adjustment process is 5-10μs, which is much faster than the PID closed-loop control used in imported equipment. This can effectively avoid local overheating and dry burning of R4 due to power adjustment lag. At the same time, by measuring the difference between OUT1 (voltage across R4) and OUT2 (voltage across R5) in the circuit, the real-time power of R4 is calculated according to the formula P=(OUT1-OUT2)*(OUT2 / R5), realizing dynamic power monitoring and abnormal alarm (when the power exceeds the range of 1.0-1.4W, the system triggers a fault signal).

[0028] In addition, the control circuit of the two A-layers connected in series is completely the same as that of the B-layer, except that the equivalent resistance of the A-layer winding is used as R4. Its temperature in equilibrium is stable at 110℃±5℃, ensuring that the auxiliary heating effect of the A-layer matches the heat demand of the B-layer.

[0029] The data acquisition-control-algorithm fusion processing system is based on the STM32F103C8T6 microcontroller, which has a main frequency of 72MHz and sufficient computing power to process multi-channel data. The system uses the ADS8320 16-bit high-speed ADC chip, with a sampling rate of up to 100kSPS and a resolution of 16 bits. It communicates with the STM32 microcontroller via the SPI bus. The sampling channels are divided into two paths: one acquires the voltage signal (OUT1-OUT2) of the B-layer winding (R4) with a sampling accuracy of ±0.5mV; the other acquires the voltage signal of the high-response-value temperature sensing resistor with a sampling accuracy of ±0.1mV. Both sampling frequencies are set to 1000Hz to ensure real-time data processing.

[0030] The STM32 microcontroller communicates with the aircraft's avionics system via a CAN bus interface (using a TJA1050 CAN transceiver) to receive information such as the aircraft's airspeed and flight status. The CAN bus communication rate is 250kbps, which conforms to the communication standards of airborne equipment. At the same time, the microcontroller reserves an RS232 interface (using a MAX232 chip) for data uploading and parameter configuration during ground debugging.

[0031] After receiving the temperature-sensing resistor voltage signal acquired by the ADC, the STM32 microcontroller calculates the actual temperature Ts (unit: K) of the B-layer winding according to the characteristic formula of platinum resistance thermometer (Rt=R0(1+αT), where R0=1000Ω, α=0.00385 / ℃). Simultaneously, based on the voltage values ​​of OUT1 and OUT2, it calculates the real-time power P_total of the B-layer winding using the formula P=(OUT1-OUT2)*(OUT2 / R5). Then, combining this with the air temperature Ta (transmitted by the aircraft avionics system via the CAN bus), the liquid water content w is derived using the following algorithm: Total power Ptotal = Pd (convective loss) + Pw (evaporative loss) + Pr (radiative loss), where Pr ≤ 5% of Pd and can be ignored. Therefore, Ptotal ≈ Pd + Pw. Convection loss Pd is calculated using the formula Pd=kA0(Ts-Ta)Re^xPr^y, where k (air thermal conductivity), Re (Reynolds number, calculated from air density ρ, velocity V, and viscosity v according to Re=ρVd / μ, where d is the diameter of the B-layer winding), and Pr (Prandt number) are obtained from the aircraft avionics system or derived from empirical data stored inside the microcontroller. Evaporation loss Pw is calculated using the formula Pw=πdlw(Lv1000+c(Ts-Tb)) (where d=0.08mm, l=50mm, Lv=40.66kJ / mol, c=4200J / (kg・K), Tb=373.15K). Combining Ptotal≈Pd+Pw, the liquid water content w (unit: g / m³) is finally calculated.

[0032] After receiving the aircraft's airspeed signal via the CAN bus, the STM32 microcontroller determines the aircraft's status. If the air speed V≤0m / s (static condition), the microcontroller outputs a low-level signal to cut off the power supply switch of the three-section hot wire induction plate (using N-channel MOSFET IRF540), and at the same time turns off the power MOSFET of the de-icing heating system to avoid the induction plate burning dry or the heating system working ineffectively when in static conditions. If the airspeed V > 0 m / s (dynamic operating condition), the microcontroller outputs a high-level signal, turns on the power supply switch of the induction plate, and starts the constant internal resistance closed-loop power control system. At the same time, it determines whether to start de-icing based on the shell temperature (collected by an additional ambient temperature sensor): when the shell temperature ≤ 5℃, the MOS transistor of the de-icing heating system is turned on; when the shell temperature ≥ 10℃, the de-icing heating system is turned off, ensuring that the de-icing process starts as needed and reducing energy consumption.

[0033] The power conversion unit employs a two-stage DC-DC conversion design: the first stage uses a wide-input DC-DC converter (model LM2596-12) to convert the 28V DC power supplied by the aircraft to 12V DC voltage, with an output current of up to 3A, powering the constant internal resistance closed-loop power control system; the second stage uses low-dropout regulators (models AMS1117-5.0 and AMS1117-3.3) to convert the 12V voltage to 5V and 3.3V respectively: the 5V voltage powers the 16-bit ADC chip and the AD8638B operational amplifier, with an output current of 1A; the 3.3V voltage powers the STM32 microcontroller, CAN transceiver, and temperature sensing resistor, with an output current of 0.5A. Filter capacitors are installed at the output terminals of the power conversion unit to reduce voltage ripple and ensure stable power supply to all components.

[0034] The signal interface unit integrates a CAN interface and an RS232 interface: The CAN interface uses a standard DB9 connector, with pins defined as follows: pin 1 GND, pin 2 CAN_L, pin 3 NC, pin 4 NC, pin 5 GND, pin 6 CAN_H, pin 7 NC, pin 8 NC, and pin 9 NC. It connects to the aircraft avionics system via shielded twisted-pair cable, with the shield grounded to prevent electromagnetic interference. The RS232 interface also uses a DB9 connector and is used for ground debugging to connect to a computer, enabling device parameter configuration and measurement data upload. A TVS transient voltage suppressor diode (model SMBJ24CA) is placed on the interface unit's PCB board to prevent damage to the internal circuitry from external voltage surges.

[0035] The de-icing heating system uses a flexible polyimide heating film with a power density of 2W / cm². It is attached to the inner wall of the equipment casing using high-temperature resistant double-sided adhesive (temperature resistance ≥120℃), achieving a bonding area of ​​over 95% to ensure uniform heat transfer to the casing surface. The heating film's power supply circuit uses an N-channel MOSFET (model IRF3205) connected in series. The MOSFET's gate is connected to the I / O port of an STM32 microcontroller, which controls its on / off state. A temperature sensor (model DS18B20) is installed on the surface of the heating film to monitor its temperature in real time. When the temperature exceeds 60℃, the microcontroller outputs a signal to cut off the MOSFET, preventing overheating damage to the heating film and establishing an over-temperature protection mechanism.

[0036] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. The LWC hot wire moisture content tester, characterized in that, It includes a device housing, mounting interface, core functional components, and external interaction module; the core functional components are integrated inside the device, and the external interaction module is adapted and installed to the device housing. The core functional components include a three-section hot-wire induction element, a high-response temperature-sensing resistor, a constant internal resistance closed-loop power control system, and a data acquisition-control-algorithm fusion processing system; the external interaction module includes a power conversion unit, a signal interface unit, and a de-icing heating system. The three-segment hot-wire induction element is coupled to a high-response-value temperature-sensing resistor, which is used to collect the actual temperature of the three-segment hot-wire induction element in real time. The constant internal resistance closed-loop power control system is electrically connected to the three-segment hot-wire induction element. The data acquisition-control-algorithm fusion processing system is communicatively connected to the high-response-value temperature-sensing resistor, the constant internal resistance closed-loop power control system, the de-icing heating system, and the external aircraft system. The power conversion unit is used to convert the external aircraft 28V power supply into the voltage required by the equipment; the signal interface unit supports the CAN / RS232 protocol; the de-icing heating system is mounted inside the equipment housing.

2. The LWC hot wire moisture content tester according to claim 1, characterized in that, The three-segment hot wire induction sheet adopts an ABA sandwich structure, wherein: layer A is a 1R alloy winding, with two sets of layers A located at both ends of layer B; layer B is a 2R alloy winding; and the high-response temperature measuring resistor is arranged inside the layer B winding.

3. The LWC hot wire moisture content tester according to claim 2, characterized in that, The two sets of A-layer 1R alloy windings are connected in series and electrically connected to an independent constant internal resistance closed-loop power control system.

4. The LWC hot wire moisture content tester according to claim 1, characterized in that, The constant internal resistance closed-loop power control system consists of an operational amplifier AD8638B, a power controller, and a 1R high-power reference resistor. The B-layer winding of the three-segment hot-wire induction chip is equivalent to a resistor R4 in the circuit, and R4 and R5 are connected in series to form a loop. The reference voltage is connected to pin 5 of the operational amplifier AD8638B, and the voltage divider signal of R4 and R5 is connected to pin 6. The operational amplifier outputs an adjustment signal to the power controller by comparing the voltage difference between pin 5 and pin 6. The system also includes a voltage divider circuit composed of resistors R1, R2, and R3.

5. The LWC hot wire moisture content tester according to claim 1, characterized in that, The data acquisition-control-algorithm fusion processing system is based on an STM32F103C8T6 microcontroller and is equipped with a 16-bit high-speed ADC chip. The 16-bit high-speed ADC chip communicates with the STM32F103C8T6 microcontroller via the SPI bus.

6. The LWC hot wire moisture content tester according to claim 1, characterized in that, The de-icing heating system is a flexible heating film structure that is attached to the inner wall of the equipment casing.

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