A ventilator wind speed control method based on electric ventilation psychrometer

Abstract

The invention discloses a ventilator wind speed control method based on an electric ventilation psychrometer, by setting the ventilator of the electric ventilation psychrometer to be speed adjustable, and transmitting the pressure value at the ball part obtained by a digital micro differential pressure gauge to a control system, a wind speed controller with a wet bulb pressure detection function is formed, and a pressure threshold range as a standard reference value is pre-set in the control system, the wind speed range actually corresponding to the pressure threshold range needs to be within the wet bulb ventilation speed interval of 2.5~4.0m / s required by the regulations, if the pressure value measured by the digital micro differential pressure gauge exceeds the upper and lower limits of the set pressure threshold range, the control system reversely adjusts the ventilator speed step by step, so that the pressure value obtained by the digital micro differential pressure gauge gradually approaches the set pressure threshold range. The invention can achieve the purpose of controlling the ventilation speed at the wet bulb to complete the psychrometer humidity measurement under complex environment, and its hardware improvement cost is low.

Description

Technical Field

[0001] The invention belongs to the technical field of instrument measurement, and in particular relates to a ventilator wind speed control method based on an electric ventilation psychrometer. Background Art

[0002] The electric ventilation psychrometer is a measuring instrument for measuring air humidity. It consists of two thermometers, a ventilator, a water cup and a radiation protection tube. It is also called an electric wet-dry bulb thermometer. Its working principle is: at a constant ventilation speed, air flows through the surface of the dry and wet bulbs. Since the wet bulb thermometer is covered with wet gauze, the moisture on its surface vaporizes, causing the wet bulb temperature to decrease. The lowered temperature value is the wet bulb temperature. After the dry and wet bulb temperatures are measured by the dry and wet bulb thermometers, the relative humidity value is calculated according to the psychrometer equation.

[0003] Electric ventilated psychrometers are often used to measure ambient humidity during field surveys. The calibration procedure for electric ventilated psychrometers JJG 993-2018 stipulates that the ventilation speed of the wet-bulb thermometer bulb should be between (2.5~4.0) m / s. However, the commonly used psychrometer ventilator has a constant speed, but the field environment is relatively complex. Parameters such as atmospheric pressure and ambient temperature have an impact on the ventilation speed. In addition, the operation of the ventilator, the degree of dust contamination, and the air flow in the environment will also affect the ventilation speed, causing the ventilation speed of the wet-bulb thermometer bulb to exceed the required range of the regulations, resulting in inaccurate humidity measurement results. Therefore, an electric ventilated psychrometer equipped with a constant speed ventilator may not meet the ventilation speed requirements for humidity measurement under complex field conditions, which greatly limits its application scenarios.

[0004] Based on this, it is urgent to develop an electric ventilation psychrometer with adjustable ventilator speed to meet the measurement needs of air humidity during actual field surveys, so as to ensure the requirements of wet-bulb ventilation speed when the psychrometer measures humidity. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] The present invention provides a ventilator wind speed control method based on an electric ventilation psychrometer, which is used to solve the problem of limited application scenarios of the electric ventilation psychrometer under complex air flow conditions, thereby meeting the measurement needs of air humidity during actual field surveys, and its hardware improvement cost is relatively low.

[0007] (II) Technical solution

[0008] The present invention discloses a ventilator wind speed control method based on an electric ventilation psychrometer, wherein the ventilator of the electric ventilation psychrometer is set as a ventilator with adjustable speed, and the ventilator wind speed control method comprises the following steps:

[0009] Step 1: Hang the electric ventilation psychrometer on the bracket system, place the air nozzle of the L-type pitot tube near the ball of the wet-bulb thermometer without touching each other, measure the total pressure and static pressure at the ball, where the total pressure port is parallel to the wind direction, and the static pressure port is perpendicular to the wind direction; the total pressure pipe at the end of the L-type pitot tube is connected to the high-pressure end of the digital micro-differential pressure gauge through a pressure pipeline, and the static pressure pipe is connected to the low-pressure end of the digital micro-differential pressure gauge through a pressure pipeline, and the digital micro-differential pressure gauge and the speed-adjustable ventilator are respectively connected to the control system;

[0010] Step 2: Set the pressure threshold range in the control system to Δp 0 ~Δp 1 ; Pressure threshold range Δp as standard reference value 0 ~Δp 1 The actual corresponding wind speed range needs to be within the range of (2.5~4.0) m / s, that is, Δp 0 The corresponding wind speed is greater than or equal to 2.5m / s and Δp 1 The corresponding wind speed is less than or equal to 4.0m / s;

[0011] Step 3: Turn on the power of the ventilator on the electric ventilation psychrometer, and the fan of the ventilator will rotate at the default speed r 0 Rotate, the control system collects the average value of the pressure values ​​measured by the digital micro differential pressure gauge multiple times , determine whether Δp is satisfied 0 ≤ ≤Δp 1 If yes, go to step 4, if no, go to step 5;

[0012] Step 4: When In Δp 0 ~Δp 1 If the wind speed test is within the range, the wind speed test ends and the fan speed r of the ventilator is kept at the default speed r when the humidity is measured in the next stage. 0 ;

[0013] Step 5: When Not in Δp 0 ~Δp 1 When in range, there are two situations:

[0014] (a) If Less than Δp 0 , pre-set the adjustment ratio λ of the fan speed r of the ventilator, perform n-times step-by-step speed increase adjustment of the fan speed, and re-collect after each speed adjustment , until Δp is satisfied 0 ≤ ≤Δp 1 Condition, at this time the fan speed is r=r 0+nλ, and execute step 6;

[0015] (b) If Greater than Δp 1 , perform m times of step-by-step speed reduction adjustment of the fan speed, and re-collect after each speed adjustment , until Δp is satisfied 0 ≤ ≤Δp 1 Condition, at this time the fan speed is r=r 0 -mλ, and execute step 6;

[0016] Step 6: Continue to run the fan at the fan speed r adjusted in step 5, so as to ensure that the wind speed near the bulb of the wet-bulb thermometer is within the set range of (2.5~4.0) m / s during humidity measurement.

[0017] Preferably, in step 2, the pressure threshold range Δp 0 ~Δp 1 It is calculated by looking up the table in the appendix of JJG 204-1980 Calibration Procedure for Meteorological Ventilation Psychrometers.

[0018] Preferably, the pressure threshold range Δp 0 ~Δp 1 Specifically, it is (5.5~10.9) Pa, and the corresponding wind speed range is: (2.7~3.8) m / s.

[0019] Preferably, the measurement range of the digital micro-differential pressure gauge covers (3.0~18.9) Pa, and the corresponding wind speed range is: (2.0~5.0) m / s.

[0020] Preferably, in step 3, after setting the data capture frequency of the control system and the digital micro differential pressure gauge, when the 10 data capture values ​​meet the condition of relative standard deviation s≤2%, the control system averages the pressure values ​​of the 10 digital micro differential pressure gauges to obtain .

[0021] Preferably, in step 5, the adjustment ratio λ is set to 10%r 0 .

[0022] Preferably, n≤5, and m is any positive integer less than 10.

[0023] Preferably, the control system may be a single chip microcomputer.

[0024] Preferably, step 7: after completing the humidity measurement in step 4 or step 6, turn off the power supply of the ventilator on the electric ventilation psychrometer.

[0025] (III) Beneficial effects

[0026] Compared with the prior art, the present invention provides a ventilator wind speed control method based on an electric ventilation psychrometer, which includes improvements in both software and hardware. In terms of hardware improvement, by changing the ventilator fan of the electric ventilation psychrometer to an adjustable wind speed type and measuring the dynamic pressure of the ball part through components such as a digital micromanometer and an L-shaped pitot tube, a wind speed controller with a pressure detection function at the wet bulb part is quickly formed. The actual wind speed value at the wet bulb part can be indirectly obtained based on the pressure value output by the digital micromanometer, and then the pressure threshold range Δp set is calculated by looking up the table in the specification JJG 204-1980. 0 ~Δp 1 , and make Δp 0 ~Δp 1 The actual corresponding wind speed range is within the (2.5~4.0) m / s range required by the JJG 993-2018 regulation, and it can be used as a standard reference value to determine whether wind speed control is required next. In addition, for pressure values ​​exceeding Δp 0 ~Δp 1 In this case, the present invention proposes a scheme for reversely adjusting the fan speed r of the ventilator step by step, so that the pressure value obtained by the digital micro differential pressure gauge gradually approaches the set threshold range Δp 0 ~Δp 1 , so that the ventilation speed is within the range of (2.5~4.0) m / s required by the regulations, so as to achieve the purpose of controlling the ventilation speed at the wet bulb of the electric ventilation psychrometer in complex environments such as the field. This method can overcome the influence of other factors on the wind speed at the bulb of the wet thermometer in complex environments. The construction method of the measurement and control environment is simple and easy, and the hardware cost is low. It expands the actual application scenarios of the electric ventilation psychrometer and ensures that the wet bulb wind speed of the electric ventilation psychrometer during humidity measurement meets the requirements of the regulations. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the present invention or 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 is a schematic diagram of a ventilator control system of an electric ventilation psychrometer in the present invention;

[0029] Figure 2 The present invention provides a flowchart of the steps of the ventilator wind speed control method based on the electric ventilation psychrometer. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are 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.

[0031] For the uncommon technical problem that is not easy to find, "the ventilator speed of the commonly used psychrometer is constant, but the outdoor environment is relatively complex. Parameters such as atmospheric pressure and ambient temperature have an impact on the ventilation speed. For example, the operation of the ventilator, the degree of dust contamination, and the air flow of the environment will also affect the ventilation speed, causing the ventilation speed of the wet-bulb thermometer bulb to exceed the required range of the regulations, resulting in inaccurate humidity measurement results", the present invention is based on Figure 1 A ventilator control system of an electric ventilation psychrometer which is easy to improve and build is designed, so that the ventilator wind speed can be adjusted and the actual wind speed at the wet bulb can be measured, and it can be combined with the present invention Figure 2 control method to solve the above problems.

[0032] In the prior art, considering that the ventilation speed of the wet-bulb thermometer bulb is positively correlated with the rotation speed of the ventilator, the two are not strictly proportional; the smaller Pitot tube is widely used for wind speed measurement, and the conventional combination is a Pitot tube + a compensated micromanometer or an inclined micromanometer or other pure water medium liquid pressure gauge to obtain the water column height difference Δh, Δh and wind speed V have a specific functional relationship (wind speed V is proportional to ), and the wind speed value V corresponding to Δh can also be obtained by looking up the table (Appendix 2 of the Verification Procedure for Meteorological Ventilation Psychrometers JJG 204-1980). However, liquid pressure gauges are prone to contamination and poor portability in the field, and cannot be automatically controlled. The liquid column height Δh of the liquid pressure gauge actually corresponds to the corresponding pressure value Δp ( ), therefore, in the present invention, a digital micro differential pressure gauge is used instead of a liquid pressure gauge to measure the pressure difference between the total pressure and the static pressure derived from the L-type Pitot tube (the actual wind speed corresponding to the dynamic pressure is ultimately measured, and this wind speed is the composite wind speed under the combined effects of the outdoor environment and the ventilator) to ensure the accuracy of the pressure measurement.

[0033] See also Figure 1As shown, the bracket system, ventilator, radiation protection tube, two dry-bulb and wet-bulb thermometers, ventilation pipe, and fixed bracket are all conventional components on the electric ventilation psychrometer measurement platform, so the connection relationship and position setting of the above conventional components are not repeated here. In addition, the present invention also newly uses an L-shaped pitot tube, a pressure pipeline, a digital micro-differential pressure gauge and a control system to measure the relevant pressure value of the wind speed of the ball part of the wet-bulb thermometer below the electric ventilation psychrometer, and the ventilator is set to a ventilator with adjustable speed to adjust the wind speed at the outlet of the ball part.

[0034] Specifically, Figure 1 As shown, the present invention places the air nozzle of the L-shaped pitot tube near the bulb part of the wet-bulb thermometer without the two contacting each other, so as to measure the total pressure and static pressure at the bulb part, wherein the total pressure port is parallel to the wind direction, and the static pressure port is perpendicular to the wind direction; the total pressure conducting pipe at the end of the L-shaped pitot tube is connected to the high-pressure end of the digital micro-differential pressure gauge through a pressure pipeline, and the static pressure conducting pipe is connected to the low-pressure end of the digital micro-differential pressure gauge through a pressure pipeline, and the digital micro-differential pressure gauge and the speed-adjustable ventilator are respectively connected to the control system, so as to measure the pressure at the wet-bulb part in real time and control the outlet wind speed of the ventilator.

[0035] In the wild and other complex wind speed environments, based on Figure 1 Based on the hardware improvement shown, the measuring principle of the ventilator wind speed control method of the electric ventilation psychrometer of the present invention is:

[0036] Firstly, the ventilator of the electric ventilation psychrometer is set to have adjustable speed through hardware improvement, and the pressure value corresponding to the actual wind speed at the wet bulb is measured by an L-type pitot tube and a digital micro differential pressure gauge. The digital micro differential pressure gauge transmits the obtained pressure value to the control system. The pressure threshold range as the standard reference value is pre-set in the control system. The wind speed range corresponding to the pressure threshold range needs to be within the wet bulb ventilation speed (2.5~4.0) m / s range required by the regulation JJG 993-2018 (which can be calculated after looking up the table). If the pressure value measured by the digital micro differential pressure gauge exceeds the upper and lower limits of the set pressure threshold range, the control system reversely adjusts the ventilator speed step by step, so that the pressure value obtained by the digital micro differential pressure gauge gradually approaches the set pressure threshold range, thereby achieving the purpose of controlling the ventilation speed at the wet bulb to complete the humidity measurement in a complex environment.

[0037] See also Figure 2 As shown, the ventilator wind speed control method based on the electric ventilation psychrometer in the present invention specifically includes the following steps:

[0038] Step 1: Hang the electric ventilation psychrometer on the bracket system, place the air nozzle of the L-type Pitot tube near the ball of the wet-bulb thermometer without touching each other, measure the total pressure and static pressure at the ball, where the total pressure port is parallel to the wind direction, and the static pressure port is perpendicular to the wind direction; the full-pressure pressure pipe at the end of the L-type Pitot tube is connected to the high-pressure end of the digital micro-differential pressure gauge through a pressure pipeline, and the static pressure pipe is connected to the low-pressure end of the digital micro-differential pressure gauge through a pressure pipeline. The digital micro-differential pressure gauge and the speed-adjustable ventilator are respectively connected to the control system.

[0039] Step 2: Set the pressure threshold range in the control system to Δp 0 ~Δp 1 ; Pressure threshold range Δp as standard reference value 0 ~Δp 1 The actual corresponding wind speed range needs to be within the range of (2.5~4.0) m / s, that is, the pressure value Δp 0 The corresponding wind speed is greater than or equal to 2.5m / s and Δp 1 The corresponding wind speed is less than or equal to 4.0m / s.

[0040] Step 3: Turn on the power of the ventilator on the electric ventilation psychrometer, and the fan of the ventilator will rotate at the default speed r 0 Rotation (r 0 The initial value of can be obtained in advance through preliminary experiments, and can meet the requirements of the regulations for wind speed at normal temperature and pressure). The control system collects the average value of the pressure values ​​measured by the digital micro differential pressure gauge multiple times. , determine whether Δp is satisfied 0 ≤ ≤Δp 1 If yes, go to step 4; if no, go to step 5.

[0041] Step 4: When In Δp 0 ~Δp 1 If the wind speed test is within the range, the wind speed test ends and the fan speed r of the ventilator is kept at the default speed r when the humidity is measured in the next stage. 0 .

[0042] Step 5: When Not in Δp 0 ~Δp 1 When in range, there are two situations:

[0043] (a) If Less than Δp 0 , pre-set the adjustment ratio λ of the fan speed r of the ventilator, perform n-times step-by-step speed increase adjustment of the fan speed, and re-collect after each speed adjustment , until Δp is satisfied 0 ≤ ≤Δp 1 Condition, at this time the fan speed is r=r 0 +nλ, and execute step 6;

[0044] (b) If Greater than Δp 1 , perform m times of step-by-step speed reduction adjustment of the fan speed, and re-collect after each speed adjustment , until Δp is satisfied 0 ≤ ≤Δp 1 Condition, at this time the fan speed is r=r 0 -mλ and proceed to step 6.

[0045] Step 6: Continue to run the fan at the fan speed r adjusted in step 5 to ensure that the wind speed near the bulb of the wet-bulb thermometer is within the set range of (2.5~4.0) m / s during humidity measurement.

[0046] It can be seen that the control method of the present invention forms a wind speed controller with wet-bulb pressure detection function by setting the ventilator of the electric ventilation psychrometer to an adjustable speed type, and transmitting the pressure value at the bulb obtained by the digital micro-differential pressure gauge to the control system, and pre-sets the pressure threshold range as a standard reference value in the control system. The wind speed range actually corresponding to the pressure threshold range needs to be within the wet-bulb ventilation speed (2.5~4.0) m / s range required by the regulations. If the pressure value measured by the digital micro-differential pressure gauge exceeds the upper and lower limits of the set pressure threshold range, the control system reversely adjusts the ventilator speed step by step so that the pressure value obtained by the digital micro-differential pressure gauge gradually approaches the set pressure threshold range. This method can achieve the purpose of controlling the ventilation speed at the wet bulb to complete the psychrometer humidity measurement in a complex environment, and its hardware improvement cost is relatively low.

[0047] Furthermore, in step 2, because the JJG 993-2018 regulation requires that the ventilation speed be maintained between (2.5 and 4.0) m / s, the ventilation speed corresponding to the pressure threshold range can be set to (2.7 to 3.8) m / s. The corresponding pressure threshold range Δp can be obtained from the table in Appendix 2 of the JJG 204-1980 Meteorological Ventilation Psychrometer Calibration Regulations. 0 ~Δp 1 : (0.56~1.11) mmH 2 O mmH2O, that is, the pressure threshold range Δp 0 ~Δp 1 Equivalent to (5.5~10.9) Pa pressure.

[0048] It should be noted that the pressure threshold range (5.5~10.9) Pa obtained by looking up the table in Regulation JJG 204-1980 can make the corresponding wind speed range within the interval of (2.7~3.8) m / s, thereby ensuring that the wind speed requirements of Regulation JJG 993-2018 are met.

[0049] In addition, in order to ensure that the instrument can measure the measured value within the specified accuracy requirements, the measurement range of the digital differential pressure gauge should at least include (0.31~1.93) mmH 2 O, equivalent to (3.0~18.9) Pa, the corresponding wind speed range is: (2.0~5.0) m / s.

[0050] Furthermore, in step 3, the data capture frequency of the control system and the digital micro differential pressure gauge is set to f (e.g., 1 Hz). When the values ​​captured by the last 10 data satisfy the value conditions (e.g., the relative standard deviation of the pressure values ​​captured by the last 10 data is s≤2%), the control system averages the pressure values ​​of the digital micro differential pressure gauge for the last 10 times to obtain .

[0051] Furthermore, in step 5, the adjustment ratio λ is set to 10%r 0 The adjustment ratio λ cannot be too large, otherwise it will easily lead to inaccurate humidity measurement results next time, and it cannot be too small, otherwise the single adjustment effect will not be strong. In addition, when λ=10%r 0 It is preferred to set n≤5 to avoid other reasons (such as pressure leakage in the connecting pipe, damage to the pressure gauge, etc.) When the pressure threshold is not within the range, the fan is prevented from speeding up without limit, which may cause the risk of motor burnout. It should also be pointed out that in order to ensure that the fan speed r is greater than 0, m can be any positive integer less than 10.

[0052] Furthermore, the method further comprises step 7: after the humidity measurement is completed in step 4 or step 6, turning off the power supply of the ventilator on the electric ventilation psychrometer.

[0053] Furthermore, the control system can be a single-chip microcomputer system such as MSP430.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling the wind speed of a ventilator based on an electric ventilation psychrometer, characterized in that: The ventilator of the electric ventilation psychrometer is set as a ventilator with adjustable speed, and the ventilator wind speed control method comprises the following steps: Step 1: Hang the electric ventilation psychrometer on the bracket system, place the air nozzle of the L-type pitot tube near the ball of the wet-bulb thermometer without touching each other, measure the total pressure and static pressure at the ball, where the total pressure port is parallel to the wind direction, and the static pressure port is perpendicular to the wind direction; the total pressure pipe at the end of the L-type pitot tube is connected to the high-pressure end of the digital micro-differential pressure gauge through a pressure pipeline, and the static pressure pipe is connected to the low-pressure end of the digital micro-differential pressure gauge through a pressure pipeline, and the digital micro-differential pressure gauge and the speed-adjustable ventilator are respectively connected to the control system; Step 2: Set the pressure threshold range in the control system to Δp0~Δp1; the wind speed range actually corresponding to the pressure threshold range Δp0~Δp1 as the standard reference value needs to be within the range of 2.5~4.0m / s; Step 3: Turn on the power of the ventilator on the electric ventilation psychrometer. The fan of the ventilator rotates at the default speed r0. The control system collects the average value of the pressure values ​​measured by the digital micro differential pressure gauge multiple times. , determine whether Δp0≤ ≤Δp1 condition, if yes, go to step 4, if no, go to step 5; Step 4: When When it is within the range of Δp0~Δp1, the wind speed test ends, and the fan speed r of the ventilator is kept at the default speed r0 when the humidity is measured in the next stage; Step 5: When When it is not within the range of Δp0~Δp1, there are two cases: (a) If If the fan speed r is less than Δp0, the adjustment ratio λ of the fan speed r of the ventilator is pre-set, and the fan speed is adjusted step by step for n times. After each speed adjustment, the data is collected again. , until Δp0≤ ≤Δp1 condition, at this time the fan speed is r=r0+nλ, and step 6 is executed; (b) If If the fan speed is greater than Δp1, the fan speed is gradually decelerated m times, and the data is collected again after each speed adjustment. , until Δp0≤ ≤Δp1 condition, at this time the fan speed is r=r0-mλ, and step 6 is executed; Step 6: Continue to run the fan at the fan speed r adjusted in step 5, so as to ensure that the wind speed near the bulb of the wet-bulb thermometer is within the set range of 2.5~4.0m / s during humidity measurement.

2. The ventilator wind speed control method based on electric ventilation psychrometer according to claim 1 is characterized in that: In step 2, the pressure threshold range Δp0-Δp1 is calculated by looking up the table in the appendix of JJG 204-1980 Meteorological Ventilation Psychrometer Verification Procedure.

3. The ventilator wind speed control method based on electric ventilation psychrometer according to claim 2 is characterized in that: The pressure threshold range Δp0~Δp1 is specifically 5.5~10.9 Pa, and the corresponding wind speed range is: 2.7~3.8 m / s.

4. The ventilator wind speed control method based on electric ventilation psychrometer according to claim 1, characterized in that: The measurement range of the digital micro differential pressure gauge covers 3.0~18.9Pa, and the corresponding wind speed range is: 2.0~5.0m / s.

5. The ventilator wind speed control method based on electric ventilation psychrometer according to claim 1, characterized in that: In step 3, after setting the data capture frequency of the control system and the digital micro differential pressure gauge, when the 10 data capture values ​​meet the condition of relative standard deviation s≤2%, the control system averages the pressure values ​​of the 10 digital micro differential pressure gauges to obtain .

6. The ventilator wind speed control method based on electric ventilation psychrometer according to claim 1, characterized in that: In step 5, the adjustment ratio λ is set to 10%r0.

7. The ventilator wind speed control method based on electric ventilation psychrometer according to claim 6, characterized in that: Set n≤5, and m to be any positive integer less than 10.

8. The method for controlling the wind speed of a ventilator based on an electric ventilation psychrometer according to claim 1, characterized in that: The control system is a single chip microcomputer system.

9. The ventilator wind speed control method based on electric ventilation psychrometer according to claim 1, characterized in that: Step 7: After completing the humidity measurement in Step 4 or Step 6, turn off the power to the ventilator on the electric vent psychrometer.

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