Air humidity measurement method, storage medium, controller and sensor

Abstract

The present invention discloses a method for measuring air humidity, a storage medium, a controller and a sensor. The method for measuring air humidity comprises the following steps: step S10, obtaining the air temperature and air pressure in the current environment; step S20, obtaining the output voltage of the air moisture sensor in the current environment; step S30, calculating the absolute air moisture content in the current environment according to the output voltage of the air moisture sensor in the current environment and the relationship between the output voltage of the air moisture sensor and the absolute air moisture content; step S40, calculating the relative air moisture content in the current environment according to the air temperature, air pressure and absolute air moisture content in the current environment. The present invention solves the problem that the air temperature and humidity sensor is difficult to accurately measure the air humidity in a high humidity environment.

Description

Technical Field

[0001] The present invention relates to the field of sensors, and in particular to a method for measuring air humidity, a storage medium, a controller and a sensor. Background Art

[0002] Ordinary IC air temperature and humidity sensors have reduced accuracy in high humidity environments (relative humidity above 95%), and there is no way to measure air humidity in a water vapor supersaturated environment (relative humidity 100%). In addition, long-term operation in an environment with extremely low or extremely high air humidity will cause dehydration or saturation, causing sensor failure. Summary of the invention

[0003] The main purpose of the present invention is to provide a method for measuring air humidity, a storage medium, a controller and a sensor, aiming to solve the problem that an air temperature and humidity sensor is difficult to accurately measure air humidity in a high humidity environment.

[0004] To achieve the above object, the present invention provides a method for measuring air humidity, which comprises the following steps:

[0005] Step S10, obtaining the air temperature and air pressure in the current environment;

[0006] Step S20, obtaining an output voltage of an air moisture sensor under a current environment, wherein the air moisture sensor comprises a first thermistor and a second thermistor, the first thermistor is sealed in absolutely dry gas, the second thermistor is not sealed, the first thermistor and the second thermistor are arranged in series between a power supply circuit and a ground electrode, and the output end of the air moisture sensor is a common end of the first thermistor and the second thermistor;

[0007] Step S30, calculating the absolute water content of the air in the current environment according to the output voltage of the air water content sensor in the current environment and the relationship between the output voltage of the air water content sensor and the absolute water content of the air;

[0008] Step S40: Calculate the relative water content of the air in the current environment according to the air temperature, air pressure and absolute water content of the air in the current environment.

[0009] Optionally, the step S20 specifically includes the following steps:

[0010] heating the first thermistor and the second thermistor;

[0011] When the first thermistor and the second thermistor reach a preset temperature, the output voltage of the air moisture sensor is obtained.

[0012] Optionally, the step S30 specifically includes the following steps:

[0013] Using a calibration compensation algorithm to calibrate and compensate the output voltage of the air moisture sensor;

[0014] The absolute water content of the air in the current environment is calculated based on the output voltage of the air water content sensor after calibration and compensation and the relationship between the output voltage of the air water content sensor and the absolute water content of the air.

[0015] Optionally, after step S30, the following steps are also included:

[0016] According to the temperature in the current environment, the temperature compensation algorithm is used to perform temperature compensation on the calculated absolute moisture content of the air;

[0017] The relative moisture content of the air in the current environment is calculated based on the absolute moisture content of the air after temperature compensation, the air temperature in the current environment, and the air pressure in the current environment.

[0018] Optionally, before step S10, the method for measuring air humidity further includes the following steps:

[0019] The relative moisture content of the air in the current environment is obtained, and when the relative moisture content of the air in the current environment is greater than a preset relative moisture content, the steps S10 to S40 are executed.

[0020] Optionally, after obtaining the relative water content of air in the current environment, the following steps are also included:

[0021] When the relative moisture content of the air in the current environment is less than or equal to the preset relative moisture content, the relative moisture content and temperature of the air in the current environment are obtained;

[0022] The absolute water content of the air in the current environment is calculated based on the relative water content and temperature of the air in the current environment.

[0023] Optionally, after step S10, the method for measuring air humidity further comprises the following steps:

[0024] When the air temperature in the current environment is greater than or equal to the preset temperature, steps S20 to S40 are performed.

[0025] The present invention provides a storage medium, on which is stored an air humidity measurement program, and when the air humidity measurement program is executed by a processor, the steps of the air humidity measurement method described above are implemented.

[0026] The present invention provides a controller, which includes a memory and a processor. The memory stores an air humidity measurement program, and when the air humidity measurement program is executed by the processor, the steps of the air humidity measurement method described above are implemented.

[0027] The present invention provides a sensor for measuring air humidity, wherein the sensor for measuring air humidity further comprises:

[0028] Air pressure sensor, used to detect the air pressure in the current environment;

[0029] Temperature sensor, used to detect the temperature in the current environment;

[0030] An air moisture sensor, the air moisture sensor comprising a first thermistor and a second thermistor, the resistance of the first thermistor and the second thermistor being arranged in series between a power supply circuit and a ground electrode, and the output end of the air moisture sensor being a common end of the first thermistor and the second thermistor;

[0031] A controller, wherein the controller is the controller as described above, and is used to control the air pressure sensor, the temperature sensor, and the air moisture sensor to obtain the air pressure and temperature under the current environment and the output voltage of the air moisture sensor;

[0032] The controller is also used to calculate the relative water content of the air in the current environment according to the air pressure and temperature in the current environment and the output voltage of the air water content sensor.

[0033] The present invention sets up a method for measuring air humidity, and calculates the relative moisture content of the air in the current environment by using the air temperature, air pressure and absolute moisture content of the air in the current environment. In order to obtain accurate relative moisture content of the air, an air moisture sensor is proposed, which includes a first thermistor sealed in absolutely dry gas and an unsealed second thermistor. The output end of the air moisture sensor is the common end of the first thermistor and the second thermistor. When the humidity of the air changes, the output voltage of the air moisture sensor changes, and the absolute moisture content of the air can be obtained according to the corresponding relationship between the output voltage of the air moisture sensor and the absolute moisture content of the air. Since the air moisture sensor measures the absolute moisture content of the air based on the change in the resistance of the thermistor, compared with the existing sensor that measures the moisture content of the air through a humidity-sensitive element, the air humidity measurement method of the present invention can still accurately measure the air humidity in an environment with extremely high humidity. The present invention solves the problem that the air temperature and humidity sensor is difficult to accurately measure the air humidity in a high humidity environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0035] Figure 1 A schematic diagram of the working process of an embodiment of a method for measuring air humidity of the present invention;

[0036] Figure 2 A schematic diagram of functional modules of an embodiment of a sensor for measuring air humidity according to the present invention;

[0037] Figure 3 for Figure 2 A schematic diagram of the circuit structure of an embodiment of an air moisture sensor.

[0038] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0041] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0042] Ordinary IC air temperature and humidity sensors generally measure the humidity of the air through humidity-sensitive elements. Humidity-sensitive elements are mainly divided into two categories: resistance type and capacitance type. The characteristic of humidity-sensitive resistors is that a film made of humidity-sensitive material is covered on the substrate. When water vapor in the air is adsorbed on the humidity-sensitive film, the resistivity and resistance value of the element change. This characteristic can be used to measure humidity. Humidity-sensitive capacitors are generally made of polymer film capacitors. When the ambient humidity changes, the dielectric constant of the humidity-sensitive capacitor changes, causing its capacitance to change as well. The change in capacitance is proportional to the relative humidity. When the air temperature and humidity sensor is in a high humidity environment (relative humidity above 95%), the humidity-sensitive material on the humidity-sensitive element will be too saturated with absorbed water vapor, affecting the measurement results of the air temperature and humidity sensor.

[0043] The present invention provides a method for measuring air humidity, aiming to solve the problem that an air temperature and humidity sensor is difficult to accurately measure air humidity in a high humidity environment.

[0044] The method for measuring air humidity comprises the following steps:

[0045] Step S10, obtaining the air temperature and air pressure in the current environment;

[0046] Step S20, obtaining an output voltage of an air moisture sensor under a current environment, wherein the air moisture sensor comprises a first thermistor and a second thermistor, the first thermistor and the second thermistor are arranged in series between a power supply circuit and a ground electrode, and an output end of the air moisture sensor is a common end of the first thermistor and the second thermistor;

[0047] Step S30, calculating the absolute water content of the air in the current environment according to the output voltage of the air water content sensor in the current environment and the relationship between the output voltage of the air water content sensor and the absolute water content of the air;

[0048] Step S40: Calculate the relative water content of the air in the current environment according to the air temperature, air pressure and absolute water content of the air in the current environment.

[0049] In this embodiment, an air moisture content sensor is provided. The absolute air moisture content AH (g / m3) in the current environment can be calculated based on the output voltage of the air moisture content sensor. After obtaining the absolute air moisture content, the air temperature t (°C) and the air pressure B (Pa) in the current environment, the relative air moisture content RH in the current environment can be calculated based on the mutual conversion relationship between them.

[0050] In one embodiment of step S10, the air temperature t (°C) and air pressure B (Pa) in the environment can be obtained through a temperature sensor and an air pressure sensor. For the temperature sensor and the air pressure sensor, corresponding temperature and humidity compensation components are set in the sensors to reduce the influence of humidity on the measurement results of the temperature sensor and the air pressure sensor, so that the temperature sensor and the air pressure sensor can still obtain accurate air temperature t (°C) and air pressure B (Pa) when the air humidity is high.

[0051] In one embodiment of step 20, the air moisture sensor includes a first thermistor and a second thermistor, wherein the first thermistor (Rdry) is sealed in an absolutely dry gas, and the second thermistor (Rair) is not sealed and contacts the gas to be measured. When the current output by the power supply circuit flows through the thermistor, the thermistor generates heat, and the resistance value of the thermistor decreases. Finally, the heat generated by the current and the heat emitted to the outside of the thermistor will be equal, reaching thermal equilibrium, and the final temperature will remain unchanged. Due to the presence of moisture in the air of the measured environment, the heat exchange rate is different from that of completely dry gas, resulting in different temperatures of the two thermistors in the final stable state. The two thermistors are arranged in series between the power supply circuit and the ground electrode. If the voltage output by the power supply circuit is constant, then when the air humidity changes, the resistance of the first thermistor and the second thermistor changes, and the voltage across the first thermistor and the second thermistor also changes. The temperature when the two thermistors are stable corresponds to the resistance value when the two thermistors are stable, and the resistance value when the two thermistors are stable corresponds to the output terminal voltage of an air moisture sensor. Therefore, the output voltage of an air moisture sensor can correspond to the temperature at which the two thermistors are stable.

[0052] At the same time, the heat exchange rate of the thermistor is related to the air humidity, and the temperature when the thermistor is stable also has a corresponding relationship with the absolute moisture content of the environment in which the thermistor is located. The absolute moisture content of the environment in which the first thermistor is located can be regarded as zero, and the absolute moisture content of the environment in which the second thermistor is located is the absolute moisture content of the air in the current environment AH. Therefore, the absolute moisture content of the air in the current environment AH can be obtained through the temperature when the two thermistors are stable.

[0053] The output voltage of an air moisture sensor can correspond to the temperature when the two thermistors are stable, and the absolute air moisture content AH in the current environment can be obtained by the temperature when the two thermistors are stable. Therefore, there is a corresponding conversion relationship between the output voltage of the air moisture sensor and the absolute air moisture content AH in the current environment.

[0054] In one embodiment of step S30, a standard absolute humidity tester and a constant temperature and humidity chamber can be used to test the air humidity sensor in use, adjust different absolute humidities, and record the sensor output voltage. The relationship between the sensor output voltage and the absolute humidity is measured, and the absolute humidity relationship can be obtained based on the sensor output voltage.

[0055] Specifically, the corresponding relationship between the output voltage of the humidity sensor and the absolute water content of the air is fitted as follows:

[0056]

[0057] Where Vout is the output voltage of the sensor, Ahraw is the original value of absolute humidity (g / m3), and the rest are fitting coefficients. The specific values ​​of each parameter in the fitting coefficients are shown in the following table:

[0058]

[0059]

[0060] In step S20, there is a corresponding conversion relationship between the output terminal voltage of the air moisture sensor and the absolute air moisture content AH in the current environment, and step S30 fits the corresponding relationship between the output voltage of the humidity sensor and the absolute air moisture content, so the absolute air moisture content can be calculated based on the output voltage of the air humidity sensor.

[0061] In one embodiment of step 40, after obtaining the absolute water content AH (g / m3) of the air, the air pressure B (Pa) measured by the pressure sensor, and the air temperature t (°C) measured by the temperature sensor, the relative water content RH of the air in the current environment can be calculated.

[0062] The parameters of moist air are as follows: T – Kelvin temperature (K), Pq – partial pressure of water vapor (Pa), Pqb – partial pressure of saturated water vapor (Pa), d – moisture content (g / kg), ρ – density of moist air (kg / m3) and RH – relative humidity;

[0063] The parameters of moist air have the following relationship: T = 273.15 + t;

[0064] Saturated water vapor partial pressure: ln(Pqb)=C8 / T+C9+C10T+C11T2+C12T3+C13ln(T), where C8~C13 are constant coefficients in the above formula;

[0065] Water vapor partial pressure: Pq = Pqb*RH;

[0066] Air humidity: d = 622Pq / (B-Pq);

[0067] Wet air density: ρ = 0.003484B / T-0.00134Pq / T;

[0068] Absolute water content: AH = 1000ρd / (d+1000);

[0069] Even in a high humidity or supersaturated environment, as long as the measurement module measures the absolute water content AH (g / m3), air pressure B (Pa) and air temperature t (℃), the current relative humidity of the air can be calculated through the above formulas.

[0070] It should be noted that the present invention can use a temperature sensor and an air pressure sensor to obtain the air temperature t (°C) and air pressure B (Pa) in the environment, and detect the absolute water content AH (g / m3) in the current environment through the output voltage of the air moisture sensor. The temperature sensor, the air pressure sensor and the air moisture sensor can still obtain accurate air temperature t (°C) and air pressure B (Pa), and absolute water content AH (g / m3) when the air humidity is high. Since the detection principle of the air moisture sensor is based on the resistance change of the thermistor, compared with the existing sensor using a humidity-sensitive element, the air moisture sensor in the present invention will not affect the detection accuracy in an environment with extremely high humidity.

[0071] The present invention sets up a method for measuring air humidity, and calculates the relative moisture content of the air in the current environment by using the air temperature, air pressure and absolute moisture content of the air in the current environment. In order to obtain accurate relative moisture content of the air, an air moisture sensor is proposed, which includes a first thermistor sealed in absolutely dry gas and an unsealed second thermistor. The output end of the air moisture sensor is the common end of the first thermistor and the second thermistor. When the humidity of the air changes, the output voltage of the air moisture sensor changes, and the absolute moisture content of the air can be obtained according to the corresponding relationship between the output voltage of the air moisture sensor and the absolute moisture content of the air. Since the air moisture sensor measures the absolute moisture content of the air based on the change in the resistance of the thermistor, compared with the existing sensor that measures the moisture content of the air through a humidity-sensitive element, the air humidity measurement method of the present invention can still accurately measure the air humidity in an environment with extremely high humidity. The present invention solves the problem that the air temperature and humidity sensor is difficult to accurately measure the air humidity in a high humidity environment.

[0072] In one embodiment of the present invention, the first thermistor and the second thermistor are heated;

[0073] When the first thermistor and the second thermistor reach a preset temperature, the output voltage of the air moisture sensor is obtained.

[0074] In this embodiment, if the thermistor is in a relatively low temperature environment, the resistance value of the thermistor does not change significantly, and the resistance values ​​of the first thermistor sealed in absolutely dry gas and the unsealed second thermistor do not change significantly. It may happen that no matter how the ambient humidity changes, due to the very low temperature, the resistance values ​​of the first thermistor and the second thermistor do not change significantly, and thus the output voltage does not change significantly, making it difficult to measure the absolute moisture content of the air.

[0075] The heat exchange effect of thermistors is more obvious at high temperatures, and the higher the temperature of the thermistor, the smaller the resistance value. When the resistance value is small, it is easier to accurately measure the resistance value through a bridge. Therefore, when the sensor starts working, a larger heating bias current is required for the thermistor to work at a higher temperature. When the thermistor reaches a higher temperature environment, the absolute moisture content of the air measured in this way can be more accurately measured.

[0076] In one embodiment of the present invention, the step S30 specifically includes the following steps:

[0077] Using a calibration compensation algorithm to calibrate and compensate the output voltage of the air moisture sensor;

[0078] The absolute water content of the air in the current environment is calculated based on the output voltage of the air water content sensor after calibration and compensation and the relationship between the output voltage of the air water content sensor and the absolute water content of the air.

[0079] In this embodiment, due to differences in the electronic components in the sensor, such as component aging, in order to obtain a more accurate sensor output voltage, the output voltage of the air moisture sensor needs to be calibrated and compensated. The air humidity sensor used can be tested using a standard absolute humidity tester and a constant temperature and humidity chamber, adjusting different absolute humidity levels and recording the sensor output voltage, and then finally obtaining a calibration compensation relationship based on the relationship between the sensor output voltage and the absolute humidity.

[0080] Specifically, the relationship for obtaining calibration compensation through fitting is:

[0081] V adj (V raw )=C d ×V raw 3 +C a xV raw 2 +C b ×V raw +C c

[0082] Ca, Cb, Cc, and Cd are all calibration parameters, which are stored in the memory. By default, Ca, Cc, and Cd are all 0, and Cb is 1. raw is the output voltage of the air humidity sensor, V adj is the voltage after calibration compensation.

[0083] In one embodiment of the present invention, the following steps are further included after step S30:

[0084] According to the temperature in the current environment, the temperature compensation algorithm is used to perform temperature compensation on the calculated absolute moisture content of the air;

[0085] The relative moisture content of the air in the current environment is calculated based on the absolute moisture content of the air after temperature compensation, the air temperature in the current environment, and the air pressure in the current environment.

[0086] In this embodiment, in order to compensate for the change of ambient temperature, which causes the instability of the circuit or the change of parameters, a negative temperature coefficient thermistor is required for compensation. The corresponding temperature compensation relationship can be fitted according to the parameters and structure of the circuit connector in the air moisture sensor.

[0087] Specifically, the temperature compensation relationship is:

[0088]

[0089] Among them, Ah raw is the absolute humidity before temperature compensation, Ah TF is the absolute humidity after temperature compensation, T is the real-time temperature of the current environment, tfa is 1.1314, and tfb is -102.4.

[0090] In one embodiment of the present invention, before step S10, the method for measuring air humidity further includes the following steps:

[0091] The relative moisture content of the air in the current environment is obtained, and when the relative moisture content of the air in the current environment is greater than a preset relative moisture content, the steps S10 to S40 are executed.

[0092] In this embodiment, when the current environment is in an extremely high air humidity environment, the humidity sensor cannot be used to obtain the air moisture content. If the moisture content in the air is too high, the humidity sensing film on the humidity sensor will be damaged, making it difficult for the humidity sensor to measure the air moisture content. At this time, the air moisture content can be measured by executing steps S10 to S40 as described above.

[0093] In one embodiment of the present invention, after obtaining the relative water content of air in the current environment, the following steps are also included:

[0094] When the relative moisture content of the air in the current environment is less than or equal to the preset relative moisture content, the relative moisture content and temperature of the air in the current environment are obtained;

[0095] The absolute water content of the air in the current environment is calculated based on the relative water content and temperature of the air in the current environment.

[0096] In this embodiment, in an environment that is not in an extremely high air humidity, the air moisture content can be obtained by the corresponding hygroscopic element. When the water vapor in the air is adsorbed on the hygroscopic film, the resistivity and resistance value of the hygroscopic element change. This characteristic can be used to measure the relative water content in the air. At the same time, the above-mentioned steps S10 to S40 can also be performed to measure the air moisture content, thereby obtaining two sets of air moisture content measurement data. Subsequent staff can evaluate the accuracy of the two measurement schemes by comparing the two measurement data. For example, when the absolute air moisture content is A1~A2, the environment is not in an extremely high air humidity at this time. The air moisture content can be obtained by comparing the hygroscopic element and the air moisture content measured by executing steps S10 to S40, and compared with the standard value, thereby evaluating which test data is better in the range of the absolute air moisture content of A1~A2.

[0097] In one embodiment of the present invention, after step S10, the method for measuring air humidity further includes the following steps:

[0098] When the air temperature in the current environment is greater than or equal to the preset temperature, the steps S20 to S40 are performed.

[0099] In the present embodiment, the thermistor is in a relatively low temperature environment, and the resistance value of the thermistor does not change significantly, and the resistance value of the first thermistor sealed in the absolutely dry gas and the unsealed second thermistor does not change significantly. It may happen that no matter how the ambient humidity changes, due to the low temperature, the resistance values ​​of the first thermistor and the second thermistor do not change significantly, so the output voltage does not change significantly, and it is difficult to measure the absolute water content of the air. In order to obtain accurate measurement data, it is necessary to keep the thermistor at a higher temperature. When the air temperature is too low, it is difficult for the thermistor to maintain a higher temperature, and it is easy to obtain inaccurate measurement data. And when the temperature is too low, when executing step S30, it is necessary to heat the thermistor, which consumes a lot of power.

[0100] Therefore, when the air environment is low, the execution of steps S20 to S40 is stopped, and a corresponding prompt signal is output to the staff to avoid power loss caused by continuing to heat the thermistor when the air temperature is too low.

[0101] The present invention provides a storage medium, on which is stored an air humidity measurement program, and when the air humidity measurement program is executed by a processor, the steps of the air humidity measurement method described above are implemented.

[0102] The present invention provides a controller, which includes a memory and a processor. The memory stores an air humidity measurement program, and when the air humidity measurement program is executed by the processor, the steps of the air humidity measurement method described above are implemented.

[0103] The detailed steps of the air humidity measurement method can be referred to the above-mentioned embodiment, which will not be repeated here; it can be understood that since the above-mentioned air humidity measurement method is used in the storage medium and the controller of the present invention, the embodiments of the storage medium and the controller of the present invention include all the technical solutions of all the embodiments of the above-mentioned air humidity measurement method, and the technical effects achieved are also exactly the same, which will not be repeated here.

[0104] The invention provides a sensor for measuring air humidity.

[0105] In one embodiment of the present invention, the sensor for measuring air humidity further includes:

[0106] Air pressure sensor, used to detect the air pressure in the current environment;

[0107] Temperature sensor, used to detect the temperature in the current environment;

[0108] An air moisture sensor, the air moisture sensor comprising a first thermistor and a second thermistor, the resistance of the first thermistor and the second thermistor being arranged in series between a power supply circuit and a ground electrode, and the output end of the air moisture sensor being a common end of the first thermistor and the second thermistor;

[0109] A controller, wherein the controller is the controller as described above, and is used to control the air pressure sensor, the temperature sensor, and the air moisture sensor to obtain the air pressure and temperature under the current environment and the output voltage of the air moisture sensor;

[0110] The controller is also used to calculate the relative water content of the air in the current environment according to the air pressure and temperature in the current environment and the output voltage of the air water content sensor.

[0111] In this embodiment, the temperature sensor, the air pressure sensor and the air moisture sensor can still obtain accurate air temperature t (°C) and air pressure B (Pa), and absolute moisture content AH (g / m3) under high air humidity conditions. Since the detection principle of the air moisture sensor is based on the change in resistance of the thermistor, compared to the existing sensors using humidity-sensitive elements, the air moisture sensor in the present invention will not affect the detection accuracy in an environment with extremely high humidity.

[0112] The detailed structure of the controller can refer to the above-mentioned embodiment and will not be described in detail here; it can be understood that since the above-mentioned controller is used in the sensor for measuring air humidity of the present invention, the embodiment of the network security transmission card of the present invention includes all the technical solutions of all the embodiments of the above-mentioned controller, and the technical effects achieved are also exactly the same, which will not be described in detail here.

[0113] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for measuring air humidity, characterized in that: The method for measuring the air humidity comprises the following steps: Step S10, obtaining the air temperature and air pressure in the current environment; Step S20, obtaining an output voltage of an air moisture sensor under a current environment, wherein the air moisture sensor comprises a first thermistor and a second thermistor, the first thermistor is sealed in absolutely dry gas, the second thermistor is not sealed, the first thermistor and the second thermistor are arranged in series between a power supply circuit and a ground electrode, and the output end of the air moisture sensor is a common end of the first thermistor and the second thermistor; Step S30, calculating the absolute water content of the air in the current environment according to the output voltage of the air water content sensor in the current environment and the relationship between the output voltage of the air water content sensor and the absolute water content of the air; Step S40: Calculate the relative water content of the air in the current environment according to the air temperature, air pressure and absolute water content of the air in the current environment.

2. The method for measuring air humidity according to claim 1, characterized in that: The step S20 specifically includes the following steps: heating the first thermistor and the second thermistor; When the first thermistor and the second thermistor reach a preset temperature, the output voltage of the air moisture sensor is obtained.

3. The method for measuring air humidity according to claim 1, characterized in that: The step S30 specifically includes the following steps: Using a calibration compensation algorithm to calibrate and compensate the output voltage of the air moisture sensor; The absolute water content of the air in the current environment is calculated based on the output voltage of the air water content sensor after calibration and compensation and the relationship between the output voltage of the air water content sensor and the absolute water content of the air.

4. The method for measuring air humidity according to claim 1, characterized in that: After step S30, the method further includes the following steps: According to the temperature in the current environment, the temperature compensation algorithm is used to perform temperature compensation on the calculated absolute moisture content of the air; The relative moisture content of the air in the current environment is calculated based on the absolute moisture content of the air after temperature compensation, the air temperature in the current environment, and the air pressure in the current environment.

5. The method for measuring air humidity according to claim 1, characterized in that: Before step S10, the method for measuring air humidity further includes the following steps: The relative moisture content of the air in the current environment is obtained, and when the relative moisture content of the air in the current environment is greater than a preset relative moisture content, the steps S10 to S40 are executed.

6. The method for measuring air humidity according to claim 5, characterized in that: After obtaining the relative water content of air in the current environment, the following steps are also included: When the relative moisture content of the air in the current environment is less than or equal to the preset relative moisture content, the relative moisture content and temperature of the air in the current environment are obtained; The absolute water content of the air in the current environment is calculated based on the relative water content and temperature of the air in the current environment.

7. The method for measuring air humidity according to claim 1, characterized in that: After step S10, the method for measuring air humidity further comprises the following steps: When the air temperature in the current environment is greater than or equal to the preset temperature, steps S20 to S40 are performed.

8. A storage medium storing an air humidity measurement program, wherein the air humidity measurement program, when executed by a processor, implements the steps of the air humidity measurement method according to any one of claims 1 to 7.

9. A controller, characterized in that: The controller includes a memory and a processor. The memory stores an air humidity measurement program. When the air humidity measurement program is executed by the processor, the steps of the air humidity measurement method according to any one of claims 1 to 7 are implemented.

10. A sensor for measuring air humidity, characterized in that: The sensor for measuring air humidity also includes: Air pressure sensor, used to detect the air pressure in the current environment; Temperature sensor, used to detect the temperature in the current environment; An air moisture sensor, the air moisture sensor comprising a first thermistor and a second thermistor, the first thermistor and the second thermistor are arranged in series between a power supply circuit and a ground electrode, and an output end of the air moisture sensor is a common end of the first thermistor and the second thermistor; A controller, wherein the controller is the controller according to claim 9, and is used to control the air pressure sensor, the temperature sensor, and the air moisture sensor to obtain the air pressure and temperature under the current environment and the output voltage of the air moisture sensor; The controller is also used to calculate the relative water content of the air in the current environment according to the air pressure and temperature in the current environment and the output voltage of the air water content sensor.

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