Wind speed detection method and system

Abstract

The application provides a wind speed detection method and system, which detects the wind speed in an application scene based on the laser reflection pulse counting rate of a particulate matter sensor, and specifically comprises the following steps: S1: receiving scattered light generated by particulate matter in airflow by using a photodetector in a single particulate matter laser detection module, and outputting a reflection pulse signal after signal processing; S2: counting the pulse number N of the reflection pulse signal within a preset sampling time window T, and calculating a pulse counting rate R=N / T; and S3: substituting the pulse counting rate R into a pre-stored mapping function v=f(R) to obtain a real-time wind speed value v. The particulate matter laser detection module is used to measure the particulate matter concentration simultaneously, and the wind speed measurement and the particulate matter concentration measurement share the same laser, the same photodetector and the same signal processing link. By using the application, the problems of high cost, large size, easy pollution and complex system caused by the dependence of the prior art on a special wind speed sensing unit are solved.

Description

Technical Field

[0001] This invention belongs to the field of air conditioning and air detection technology, and particularly relates to a wind speed detection method and system. Background Technology

[0002] In the field of air conditioning, which involves temperature and humidity, or in areas with special ventilation standards, such as spaces where airflow acts as a shield, precise dynamic monitoring of wind speed is required. Existing wind speed detection methods (such as thermal, differential pressure, and ultrasonic methods) require a dedicated, independent wind speed sensing unit, including a sensing element, signal conditioning circuitry, and housing. This increases hardware costs, PCB area, and system power consumption, and necessitates additional installation space in integrated products (such as air quality monitors), making miniaturization difficult.

[0003] For example, Chinese invention patent application CN201810142190.X, "A method and apparatus for measuring air velocity and particulate matter content in the air," describes a method for simultaneously measuring air velocity and particulate matter content. The core steps include: using two laser particle counters to measure airborne particulate matter passing through the same channel, obtaining the output functions of the two laser particle counters respectively; establishing a cross-correlation function based on the two output functions, and finding the peak to obtain a time delay estimate of the airborne particulate matter motion; calculating the wind speed in the channel based on the time delay estimate; and calculating the number of airborne particulate matter per unit volume in the channel based on the calculated wind speed. Its formulaic expression is: x1(t) = s(t) + n1(t), x2(t) = s(t + τ) + n2(t), where τ is the time delay estimate obtained through cross-correlation peak finding.

[0004] While the aforementioned patent applications attempt to measure wind speed based on particulate matter signals, they require two laser particle counters to calculate wind speed by obtaining delay estimates through cross-correlation operations. This adds an extra set of complete sensor hardware and optical path systems, doubling the hardware cost. Furthermore, the high complexity of cross-correlation operations makes them unsuitable for low-cost embedded devices. Independent wind speed sensors (especially thermal and mechanical types) are easily affected by dust and oil buildup due to prolonged exposure to airflow, impacting heat dissipation or rotational balance, leading to zero-point drift and decreased sensitivity. Regular cleaning or calibration is required, resulting in high maintenance costs and making them unsuitable for long-term unattended scenarios. Although laser Doppler velocimetry offers high accuracy, it requires coherent light sources, precise interferometric optical paths, and high-speed spectral analysis, making the system complex and extremely expensive. This limits its application to low-cost, mass-produced embedded devices or consumer products. Existing particulate matter sensors are only used for concentration measurement. In situations requiring simultaneous monitoring of particulate matter concentration and wind speed, two relatively independent sensors must be installed, resulting in resource waste and redundant design. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention aims to provide a method and system for measuring wind speed by directly utilizing the number of reflected signals from an existing particulate matter laser detection module without requiring an additional wind speed sensing unit.

[0006] Specifically, according to the wind speed detection method of the present invention, wind speed in air conditioning application scenarios is detected based on the laser reflection pulse count rate of a particulate matter sensor, and specifically includes the following steps: Step S1: The photodetector in the single particulate matter laser detection module receives the scattered light generated by the particulate matter in the airflow, and outputs the reflected pulse signal after signal processing; Step S2: Within the preset sampling time window T, count the number N of the reflected pulse signal and calculate the pulse counting rate R = N / T; Step S3: Substitute the pulse counting rate R into the pre-stored mapping function v=f(R) to calculate the real-time wind speed value v. The particulate matter laser detection module is used to measure particulate matter concentration, and the wind speed measurement and particulate matter concentration measurement share the same laser, the same photodetector, and the same signal processing link.

[0007] Furthermore, in the wind speed detection method of the present invention, in step S3, before substituting into the mapping function, the pulse count rate R is further corrected by concentration compensation based on the real-time particulate matter concentration value C synchronously output by the particulate matter laser detection module, to obtain the corrected pulse count rate R. corr Then substitute it into the mapping function v=f(R) corr Calculate the real-time wind speed value.

[0008] Furthermore, in the wind speed detection method of the present invention, the concentration compensation correction adopts the following formula: R corr =R×(C0 / C), where C0 is the preset reference particulate matter concentration value and C is the real-time particulate matter concentration value.

[0009] Furthermore, in the wind speed detection method of the present invention, the sampling time window T is a fixed value, which can be configured by the user according to the response speed requirements, or adaptively adjusted by the system according to the pulse count rate.

[0010] Furthermore, in the wind speed detection method of the present invention, the mapping function v=f(R) is obtained through pre-calibration. The calibration process includes: measuring the corresponding pulse count rate under known wind speed conditions, establishing the correspondence between the pulse count rate and the wind speed, and fitting a linear function, a piecewise linear function, or a polynomial function as the mapping function.

[0011] Furthermore, the present invention also provides a wind speed detection system, employing any of the above-mentioned wind speed detection methods, comprising: A particulate matter laser detection module includes: a laser for emitting a laser beam to irradiate particulate matter in an airflow channel; a photodetector for receiving scattered light generated by particulate matter and converting it into a current signal; and a signal shaping circuit for amplifying, comparing, and converting the current signal into a standard square wave pulse signal. The microcontroller module includes: a pulse counter connected to the signal shaping circuit for counting the square wave pulse signal; a timer for setting a sampling time window; a counting rate calculation module for calculating the pulse counting rate based on the pulse count value and the sampling time window; and a mapping function module for mapping the pulse counting rate to a real-time wind speed value. The microcontroller module reuses the square wave pulse signal generated by the particulate matter laser detection module, and simultaneously outputs particulate matter concentration value and real-time wind speed value, without the need for an additional independent wind speed sensor.

[0012] Furthermore, in the wind speed detection system of the present invention, the microcontroller module further includes a concentration compensation module. The concentration compensation module is used to obtain the real-time particulate matter concentration value output by the particulate matter laser detection module, and to correct the pulse counting rate according to the real-time particulate matter concentration value, and to send the corrected pulse counting rate to the mapping function module.

[0013] Furthermore, in the wind speed detection system of the present invention, the signal shaping circuit includes a transimpedance amplifier and a comparator. The transimpedance amplifier converts the current signal of the photodetector into a voltage signal, and the comparator compares the voltage signal with an adjustable threshold voltage and outputs a square wave pulse signal.

[0014] Furthermore, in the wind speed detection system of the present invention, the mapping relationship stored in the mapping function module is a linear function, a piecewise linear function, or a polynomial function, and the mapping relationship is obtained by pre-calibration in a wind tunnel.

[0015] Furthermore, in the wind speed detection system of the present invention, within the range of the sampling time window T, the pulse counter triggers an interrupt at the end of each sampling window under the control of the timer, reads the current pulse count value, clears it to zero, and then starts the next cycle counting.

[0016] This invention reduces system cost and complexity by reusing the laser, detector, and signal processing pathways of a particulate matter sensor. Wind speed is obtained solely through software algorithms that calculate the pulse count rate, eliminating the need for additional hardware. Furthermore, it improves reliability and maintenance-free operation: the absence of additional thermal films or mechanical components avoids zero-point drift and performance degradation caused by contamination, making it suitable for long-term maintenance-free operation. It also enables miniaturization and integration: without increasing the number or size of sensors, it facilitates integration into compact devices such as air quality monitors, duct inspection systems, and cleanroom controls. Moreover, this invention achieves fast response speed: pulse counting can be completed in milliseconds, enabling real-time dynamic tracking of wind speed changes.

[0017] In summary, this invention solves the problems of high cost, large size, easy contamination, and system complexity caused by the reliance on dedicated wind speed sensing units in existing technologies, and provides a new wind speed detection method that is low-cost, highly reliable, and easy to integrate. Attached Figure Description

[0018] Figure 1 This is a schematic diagram illustrating the flow of a wind speed detection method according to a preferred embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram showing the structure of a wind speed detection system according to a preferred embodiment of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Other embodiments or modifications obtained by those skilled in the art based on the embodiments of this application without creative effort are all within the scope of protection of this application.

[0021] To better understand the advantages of the present invention, a summary of conventional wind speed detection methods is provided.

[0022] Existing Solution 1: Separate combination of particulate matter concentration sensor and wind speed sensor Many air quality monitoring devices (such as portable air quality monitors and duct inspection systems) integrate both laser particulate matter sensors and independent electronic anemometers (such as hot-film or ultrasonic sensors). Their operating steps are as follows: 1. The laser particulate matter sensor measures PM concentration independently and outputs the concentration value independently; 2. The wind speed sensor is placed in another location in the airflow channel or in the same channel, and outputs the wind speed value; 3. The main controller reads data from the two sensors respectively, which are used for air quality assessment and air volume calculation.

[0023] The disadvantages of this solution are: it requires two independent sensing units, which increases hardware cost, PCB area and system power consumption; the wind speed sensor is susceptible to dust contamination, which can cause zero drift and requires regular calibration; and the two sensors may have different measurement positions, which introduces measurement errors.

[0024] Existing Solution 2: Particulate Velocity Measurement Based on Laser Doppler Velocity Measurement Laser Doppler velocimetry uses two coherent laser beams to form interference fringes. When particles flow through the fringed region, the scattered light produces a Doppler frequency shift, the amount of which is proportional to the particle velocity. This method can directly measure the velocity of moving particles, thereby obtaining the airflow velocity. Its typical steps are as follows: 1. The laser output is split into two coherent beams by a beam splitter and a lens, and the interference fringe region serves as the velocity measuring body. 2. When particulate matter passes through the velocimeter, the frequency of the scattered light received by the detector is frequency-shifted compared to the incident light frequency; 3. Obtain the frequency shift using a photodetector and spectral analysis to calculate the particle velocity.

[0025] This technology offers high precision, but the system is complex (requiring coherent light sources, precise interferometric optical paths, and high-frequency signal processing), and expensive. It is mostly used in laboratories or for high-precision industrial measurements and cannot be applied to consumer-grade or low-cost embedded devices.

[0026] In summary, the shortcomings of existing solutions include: discrete sensor solutions: high cost, large size, easy contamination, and require additional calibration; laser Doppler solutions: complex system, extremely high cost, and unsuitable for mass production.

[0027] None of the above solutions utilize the direct mapping relationship between the reflected pulse count rate and wind speed of ordinary particulate matter sensors (incoherent light sources).

[0028] like Figure 1 As shown, a preferred embodiment of the wind speed detection method according to the present invention detects wind speed in an application scenario based on the laser reflection pulse count rate of a particulate matter sensor, specifically including the following steps: Step S1: The photodetector in a single particulate matter laser detection module receives the scattered light generated by particulate matter in the airflow, and outputs a reflected pulse signal after signal processing; Step S2: Within a preset sampling time window T, the number N of the reflected pulse signal is counted, and the pulse count rate R = N / T is calculated; Step S3: The pulse count rate R is substituted into a pre-stored mapping function v = f(R) to calculate the real-time wind speed value v, wherein the particulate matter laser detection module is also used to measure particulate matter concentration, and the wind speed measurement and particulate matter concentration measurement share the same laser, the same photodetector, and the same signal processing link.

[0029] The concentration C is determined as follows: the concentration C is obtained by calibrating the sampled signal with the standard signal, measuring in the same period, sampling synchronously, and using a fixed sampling time window. C0 is the actual concentration value obtained using a standard detection instrument. When the concentration exceeds the compensation range, data processing will be performed according to the processing algorithm to filter out noise signals.

[0030] The wind speed detection method according to a preferred embodiment of the present invention utilizes the positive correlation between the number of reflected pulses generated by a laser particulate sensor in the airflow and the airflow velocity. The real-time wind speed value is calculated by statistically analyzing the number of pulses per unit time (pulse counting rate) and then applying a pre-calibrated mapping function. The entire solution requires no additional hardware; only a pulse counting and conversion module needs to be added to the existing particulate sensor's signal processing software.

[0031] Airflow passes through the particulate matter detection channel. Under the control of the drive circuit, the laser emits a continuous or pulsed laser beam, illuminating the suspended particulate matter in the airflow channel. The scattered light from the particulate matter is received by a photodetector and converted into a weak current signal. This current is converted into a voltage signal by a transimpedance amplifier, and then sent to a comparator / shaping circuit. It is compared with an adjustable threshold voltage, and a standard square wave pulse is output. The processor internally includes a pulse counter, a timer, a count rate calculation module, a mapping function module, and an optional concentration compensation module. Finally, the wind speed value is output through the output interface.

[0032] Step 1: After the system is powered on, complete the initialization, configure the timer to work in periodic interrupt mode, configure the pulse counter to be triggered by the rising edge, and set the interrupt priority; Step 2: The user or program presets the sampling time window T; Step 3: Start the timer to begin the countdown, while simultaneously resetting the pulse counter to zero and starting to count the shaped pulse signal; Step 4: While the timer is not overflowing, the counter continues to accumulate pulses; Step 5: Timer overflow triggers an interrupt, read the current count value N; Step 6: Calculate the count rate R = N / T; Step 7: If the concentration of particulate matter in the environment fluctuates greatly, read the real-time concentration value C through the particulate matter concentration sensor for compensation; Step 8: Substitute R (and C) into the pre-calibrated mapping function for fitting; Step 9: Output wind speed data.

[0033] By analyzing the specific embodiments of the present invention described above, it can be seen that: 1. This invention utilizes the number of reflected pulses from a particulate matter laser sensor to invert wind speed without requiring additional wind speed sensing elements. In the prior art, particulate matter sensors are only used for concentration measurement, and their pulse signals are regarded as "noise" or only used for counting concentration. This invention is the first to recognize that there is a positive correlation between pulse counting rate and airflow speed, and actively uses it as a carrier of wind speed information.

[0034] 2. This invention measures wind speed based on a mapping function between pulse count rate and wind speed within a fixed time window. Existing discrete sensor solutions either directly read wind speed counts or measure speed through complex physical models. This invention creatively transforms the problem into statistical pulse event frequencies, which are then converted into wind speed using a pre-calibrated mapping function (linear or piecewise). This conversion does not rely on fluid dynamics or thermodynamic equations but is based on empirical fitting, greatly simplifying the calculation.

[0035] The count rate R = N / T is calculated by counting the number of pulses N within a preset sampling window T, and then the real-time wind speed is output according to the pre-stored mapping relationship v = f(R).

[0036] 3. This invention uses the particulate matter concentration value output by the same sensor to compensate for wind speed measurement. In practical applications, changes in particulate matter concentration can interfere with the relationship between pulse counting rate and wind speed. Existing technologies do not consider this problem. This invention, while utilizing pulse counting, proposes introducing concentration information as a correction factor to compensate for errors caused by concentration fluctuations. This is the improvement of this invention. This invention corrects the pulse counting rate R based on the ratio of real-time particulate matter concentration C to reference concentration C0 (e.g., R0). corr =R×(C0 / C)), and then use the corrected count rate to calculate the wind speed step or module.

[0037] 4. This invention reuses the existing hardware architecture of particulate matter sensors (laser, detector, amplifier, shaping circuit), and adds wind speed output function only through software algorithm. If existing technology wants to measure concentration and wind speed at the same time, it requires two sets of sensor hardware. This invention proves that wind speed measurement can be achieved by adding a pulse counting and mapping software module to the end of the signal processing link of the existing particulate matter sensor. This reflects the low-cost innovation of "software and hardware synergy".

[0038] In addition, such as Figure 2As shown, a wind speed detection system according to a preferred embodiment of the present invention includes: a particulate matter laser detection module, comprising: a laser for emitting a laser beam to irradiate particulate matter in an airflow channel; a photodetector for receiving scattered light generated by particulate matter and converting it into a current signal; and a signal shaping circuit for amplifying and comparing the current signal to convert it into a standard square wave pulse signal; and a microcontroller module, comprising: a pulse counter connected to the signal shaping circuit for counting the square wave pulse signal; a timer for setting a sampling time window; a counting rate calculation module for calculating the pulse counting rate based on the pulse count value and the sampling time window; and a mapping function module for mapping the pulse counting rate to a real-time wind speed value. The microcontroller module reuses the square wave pulse signal generated by the particulate matter laser detection module and simultaneously outputs particulate matter concentration and real-time wind speed values, eliminating the need for an additional independent wind speed sensor.

[0039] The specific embodiments of the present invention described above have the following significant advantages over existing wind speed detection methods, and these advantages directly stem from the targeted improvements made by the present invention to address the shortcomings of the prior art: (1) Cost and volume are significantly reduced Existing technologies require additional dedicated sensor components (such as thermal films, ultrasonic transducers, or pitot tubes) to measure wind speed, leading to increased material costs and installation space requirements. This invention directly reuses the laser, detector, amplification and shaping circuitry, and processor of a laser particulate sensor, requiring only the addition of a pulse counting and mapping conversion software module to the processor, without any additional hardware. Therefore, in applications requiring simultaneous particulate matter concentration and wind speed measurement (such as air quality monitors, air purifiers, and ventilation ducts), a complete wind speed sensor and its signal conditioning circuitry can be eliminated, resulting in lower overall hardware costs and a more compact device.

[0040] (2) Reliable long-term operation and maintenance-free Thermal and mechanical anemometers, when exposed to dusty airflows for extended periods, are prone to zero-point drift and decreased sensitivity due to contaminant adhesion, requiring regular cleaning and calibration. This invention utilizes the existing optical detection path of a particulate sensor, eliminating the need for additional moving parts or heating elements. The sensor itself does not introduce new contamination-sensitive interfaces when measuring wind speed. Practical experience shows that laser scattering particulate sensors typically have a lifespan exceeding 20,000 hours in dusty environments, and since wind speed measurement relies entirely on a stable pulse count signal, this invention provides wind speed measurement with the same high reliability as particulate sensors, making it suitable for unattended, maintenance-free, long-term online monitoring.

[0041] (3) Fast response speed, suitable for dynamic wind speed monitoring Existing thermal anemometers typically have a step response time of 0.5 to 2 seconds due to thermal inertia; ultrasonic anemometers, while fast, are expensive. This invention is based on single-particle event counting, with a sampling window as short as 0.1 seconds or even 50 milliseconds. Combined with digital filtering, it can still achieve millisecond-level response. For example, when the wind speed suddenly changes from 0.5 m / s to 3 m / s, the pulse count rate can reflect the change in the next sampling cycle, which is several times to an order of magnitude faster than thermal sensors. This makes it highly suitable for scenarios such as ventilation control with rapidly fluctuating wind speeds and wind speed sensing for drones.

[0042] (4) High integration, facilitating system-level reuse In many embedded products, particulate matter sensors are already standard modules. This invention requires no modification to the module hardware; simply adding a processor interrupt capture function to its output pulse signal line allows for the output of wind speed information in addition to the original concentration data.

[0043] In summary, this invention achieves wind speed detection at extremely low marginal cost, solving the fundamental problem in the prior art that "a dedicated sensor must be added to measure wind speed".

[0044] Compared with previous technologies, this application is highly inventive, at least in the following aspects.

[0045] First, it breaks away from the mindset of "interference compensation" and for the first time clearly proposes the fundamental understanding of "positive correlation between pulse count rate and wind speed," transforming it from an interference source into a usable signal source.

[0046] Secondly, it eliminates the need for complex calculations such as cross-correlation and peak finding; speed measurement can be completed simply by counting the number of pulses. Existing wind speed detection methods typically employ cross-correlation schemes, requiring two counters, calculation of the cross-correlation function, and peak finding. This application differs from existing technologies in terms of computational complexity by orders of magnitude, which is directly related to the technical positioning of this application (low cost, embedded).

[0047] Third, a concentration compensation scheme (R) is proposed. corr =R×(C0 / C)) to eliminate measurement errors caused by particulate matter concentration fluctuations. This is a targeted improvement scheme proposed after recognizing the nonlinear interference factors in the pulse count rate-wind speed relationship. No similar compensation mechanism is involved in existing documents.

[0048] Furthermore, it should be noted that the inventors of this invention have broken through the barriers of conventional thinking in this technical field. In existing technologies, pulse counting is typically understood as a concentration measurement method, and those skilled in the art would not usually consider that the same pulse signal could be used for wind speed measurement. Moreover, the inventors have overcome technical biases. Researchers in this field have long understood that the pulse count rate is affected by both wind speed and concentration, which is considered a source of measurement error. Transforming the "source of error" into an "information source" requires overcoming long-standing technical biases. Furthermore, existing technologies contain many counterintuitive teachings; for example, to measure wind speed, two counters are needed to calculate the speed through the time difference. This technical solution essentially conveys the teaching that "one counter is insufficient to measure wind speed." This application achieves wind speed measurement using only one counter, precisely breaking through this inherent perception.

[0049] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0050] The various embodiments in this specification are described in a related manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0051] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

[0052] The above embodiments of the present invention are merely examples for clearly illustrating the present invention and are not intended to limit the implementation of the present invention. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively describe all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A wind speed detection method, which detects wind speed in air conditioning applications based on the laser reflection pulse count rate of a particulate matter sensor, characterized in that, Includes the following steps: Step S1: The photodetector in the single particulate matter laser detection module receives the scattered light generated by the particulate matter in the airflow, and outputs the reflected pulse signal after signal processing; Step S2: Within the preset sampling time window T, count the number N of the reflected pulse signal and calculate the pulse counting rate R = N / T; Step S3: Substitute the pulse counting rate R into the pre-stored mapping function v=f(R) to calculate the real-time wind speed value v. The particulate matter laser detection module is used to measure particulate matter concentration, and the wind speed measurement and particulate matter concentration measurement share the same laser, the same photodetector, and the same signal processing link.

2. The wind speed detection method according to claim 1, characterized in that, In step S3, before substituting into the mapping function, the pulse counting rate R is also corrected for concentration compensation based on the real-time particulate matter concentration value C synchronously output by the particulate matter laser detection module, to obtain the corrected pulse counting rate R. corr Then substitute it into the mapping function v=f(R) corr Calculate the real-time wind speed value.

3. The wind speed detection method according to claim 2, characterized in that, The concentration compensation correction is calculated using the following formula: R corr =R×(C0 / C), where C0 is the preset reference particulate matter concentration value and C is the real-time particulate matter concentration value.

4. The wind speed detection method according to claim 1, characterized in that, The sampling time window T is a fixed value, which can be configured by the user according to the response speed requirements, or adaptively adjusted by the system according to the pulse count rate.

5. The wind speed detection method according to claim 1, characterized in that, The mapping function v=f(R) is obtained through pre-calibration. The calibration process includes: measuring the corresponding pulse count rate under known wind speed conditions, establishing the correspondence between the pulse count rate and the wind speed, and fitting a linear function, a piecewise linear function, or a polynomial function as the mapping function.

6. A wind speed detection system, utilizing the wind speed detection method according to any one of claims 1 to 5, characterized in that, include: A particulate matter laser detection module includes: a laser for emitting a laser beam to irradiate particulate matter in an airflow channel; a photodetector for receiving scattered light generated by particulate matter and converting it into a current signal; and a signal shaping circuit for amplifying, comparing, and converting the current signal into a standard square wave pulse signal. The microcontroller module includes: a pulse counter connected to the signal shaping circuit for counting the square wave pulse signal; a timer for setting a sampling time window; a counting rate calculation module for calculating the pulse counting rate based on the pulse count value and the sampling time window; and a mapping function module for mapping the pulse counting rate to a real-time wind speed value. The microcontroller module reuses the square wave pulse signal generated by the particulate matter laser detection module, and simultaneously outputs particulate matter concentration value and real-time wind speed value, without the need for an additional independent wind speed sensor.

7. The wind speed detection system according to claim 6, characterized in that, The microcontroller module also includes a concentration compensation module, which is used to obtain the real-time particulate matter concentration value output by the particulate matter laser detection module, correct the pulse counting rate according to the real-time particulate matter concentration value, and send the corrected pulse counting rate to the mapping function module.

8. The wind speed detection system according to claim 6, characterized in that, The signal shaping circuit includes a transimpedance amplifier and a comparator. The transimpedance amplifier converts the current signal of the photodetector into a voltage signal, and the comparator compares the voltage signal with an adjustable threshold voltage and outputs a square wave pulse signal.

9. The wind speed detection system according to claim 6, characterized in that, The mapping relationships stored in the mapping function module are linear functions, piecewise linear functions, or polynomial functions, and these mapping relationships are obtained by pre-calibration in a wind tunnel.

10. The wind speed detection system according to claim 6, characterized in that, Within the range of the sampling time window T, the pulse counter, under the control of the timer, triggers an interrupt at the end of each sampling window, reads the current pulse count value, clears it to zero, and then starts counting for the next cycle.

Images