System and method for testing acoustic directive propagation of wind turbine generator

Abstract

The invention discloses a wind turbine generator acoustic directional propagation test system and method, and the system comprises an acoustic base station which is used for collecting and transmitting acoustic data; the meteorological base station is used for collecting and transmitting meteorological data; the master control base station is used for collecting and transmitting master control parameters of the wind turbine generator; the central base station is used for receiving the acoustic data, the meteorological data and the main control parameters, and performing multi-dimensional and multi-angle fusion processing according to the received acoustic data, meteorological data and main control parameters to obtain acoustic propagation characteristics of the wind turbine generator in different directions, different unit operation states and different meteorological environments; the method measures the acoustic propagation characteristics of the wind turbine generator from a plurality of acoustic parameters and a plurality of directivity angles, considers the influence of unit operation, weather and other factors on the acoustic characteristics, considers the influence of yaw on the directivity angles, optimizes the data transmission mode, reduces the precision influence caused by manual operation, and improves the accuracy of the wind turbine generator. And a noise reduction reference basis is provided from a wind turbine generator control strategy.

Description

Technical Field

[0001] The invention relates to the technical field of wind turbine noise directional propagation testing, and in particular to a wind turbine acoustic directional propagation testing system and method. Background Art

[0002] As wind turbines develop larger megawatt capacity and longer blades, the noise generated by wind turbines also increases. Wind turbine noise consists of electromagnetic noise, mechanical noise, and aerodynamic noise. In mid- and long-range environments, the aerodynamic noise generated by the blades is the main noise contributor. When evaluating outdoor noise tests and calculating sound propagation attenuation, wind turbine noise is generally considered a point sound source. At present, the diameter of the wind rotor has exceeded 200 meters. The aerodynamic noise generated by the huge wind rotor of the wind turbine is closer to a line sound source or a surface sound source. The noise propagation of the wind turbine in different directions around it is also different, such as upwind, downwind, and sidewind directions of the wind turbine.

[0003] The existing relevant standards all use A sound level as the basis for evaluating the noise impact on residential areas. For wind turbines, the noise emitted at a certain distance and under specific operating conditions of the wind turbines may be lower than the limit requirements, but due to their spectral characteristics and directionality, there is still noise impact on nearby residential areas.

[0004] Currently, the most commonly used method for measuring the acoustic directivity of wind turbines is to use a handheld sound level meter to collect sound pressure levels at fixed points manually. It does not consider the impact of changes in sound sources such as the wind turbine rotor speed and blade pitch angle, nor does it consider the impact of meteorological data on acoustics. When the azimuth of the cabin changes, the test point cannot be changed in a timely and accurate manner, the measurement method cannot be accurate, and the measurement results cannot reflect the acoustic characteristics in detail. In summary, this method cannot effectively and accurately measure the acoustic directivity law of wind turbines.

[0005] The existing technical documents on wind turbine noise testing in this industry are as follows:

[0006] Chinese invention patent application CN108801447A discloses a wind turbine noise testing system and method, which provides data acquisition hardware, testing systems, solutions, etc. that meet the standards based on wind turbine generator set testing method standards.

[0007] Chinese invention patent application CN108489600A discloses a wind turbine noise test and evaluation system and method. This invention solves the problems of long cables, complicated operations, and low measurement and evaluation efficiency in the prior art by combining lower computer hardware data acquisition with upper computer data preservation.

[0008] Chinese invention patent application CN104034411A discloses a distributed noise measurement system for wind turbines. The invented system includes an acoustic measurement terminal, a wireless communication base station, an acoustic signal processing center, a system interaction center, etc.

[0009] In summary, there are currently no relevant patents that provide specific measurement layout plans, equipment installation locations, quantity requirements, etc. For directivity testing, there is no method for confirming the position between the acoustic measurement point and the changing wind rotor. For signal acquisition of the unit under test, key parameters that affect aeroacoustics, such as wind rotor speed, blade angle, cabin wind speed, wind rotor position, etc., are not included. The current distributed measurement system cannot accurately guide the measurement of acoustic directivity propagation of wind turbines.

[0010] Therefore, it is necessary to study the wind turbine acoustic propagation directional propagation test method and system. From the perspective of active noise reduction control of wind turbines, through the directional characteristics of acoustic propagation, the noise reduction control plan can be refined to effectively avoid power generation loss and reduce acoustic impact. Summary of the invention

[0011] The purpose of the present invention is to overcome the shortcomings of the prior art and propose a wind turbine acoustic directional propagation test system and method, which measures the acoustic propagation characteristics of the wind turbine from multiple acoustic parameters and multiple directional angles. The test system takes into account the influence of factors such as unit operation and meteorology on the acoustic characteristics, and the test equipment takes into account the influence of yaw on the directional angle. At the same time, it optimizes the data transmission method and power supply method, reduces the accuracy impact and efficiency problems caused by human operation, and provides a reference theoretical basis for noise reduction from the wind turbine control strategy.

[0012] The purpose of the present invention is achieved through the following technical solution: A wind turbine acoustic directional propagation test system, comprising:

[0013] Acoustic base stations, used to collect and transmit acoustic data, the acoustic base stations are respectively arranged at corresponding positions of the upwind direction, left wind direction, downwind direction and right wind direction of the wind turbine, and the distance between each acoustic base station and the center of the wind turbine tower is not less than H+D / 2, where H is the hub height of the wind turbine and D is the rotor diameter of the wind turbine;

[0014] A meteorological base station, used for collecting and transmitting meteorological data, wherein the meteorological base station is installed at a distance of D-2D from the wind turbine and away from the rear of the wind turbine rotor;

[0015] A main control base station, used for collecting and transmitting the main control parameters of the wind turbine set, the main control base station is arranged at the main control structure of the wind turbine set, the main control parameters include power, speed, blade angle, cabin wind speed and cabin azimuth;

[0016] The central base station is used to receive acoustic data, meteorological data and main control parameters, and perform multi-dimensional and multi-angle fusion processing based on the received acoustic data, meteorological data and main control parameters to obtain the acoustic propagation characteristics of wind turbines in different directions, different unit operating states and different meteorological environments.

[0017] Further, the acoustic base station comprises:

[0018] An acoustic data acquisition module, used for collecting acoustic data;

[0019] Power supply module, used for powering the acoustic data acquisition module, wireless transmission module and positioning module;

[0020] A wireless transmission module for transmitting acoustic data to a central base station;

[0021] A positioning module, used to obtain the location information of the acoustic base station;

[0022] The power supply module is electrically connected to the acoustic data acquisition module, the wireless transmission module and the positioning module respectively, and the acoustic data acquisition module and the positioning module are communicatively connected to the wireless transmission module respectively;

[0023] A sound pressure sensor, an acoustic calibrator and a bracket are installed at the acoustic base station, a sound level meter and a windproof ball are installed on the bracket, and the sound pressure sensor, the acoustic calibrator and the sound level meter are respectively connected to the acoustic data acquisition module for communication.

[0024] Further, the meteorological base station comprises:

[0025] Meteorological data collection module, used for collecting meteorological data;

[0026] Power supply module, used for powering the meteorological data acquisition module and the wireless transmission module;

[0027] A wireless transmission module for transmitting meteorological data to a central base station;

[0028] The power supply module is electrically connected to the meteorological data acquisition module and the wireless transmission module respectively, and the meteorological data acquisition module is communicatively connected to the wireless transmission module;

[0029] A meteorological wind tower is installed at the meteorological base station. A wind speed sensor, a wind direction sensor, a temperature sensor and an air pressure sensor are installed on the meteorological wind tower. The wind speed sensor, wind direction sensor, temperature sensor and air pressure sensor are respectively connected to the meteorological data acquisition module for communication.

[0030] Further, the master control base station includes:

[0031] Main control data acquisition module, used to collect main control parameters of wind turbines;

[0032] Power supply module, used for powering the main control data acquisition module, wireless transmission module and positioning module;

[0033] A wireless transmission module, used to transmit the master control parameters to the central base station;

[0034] Positioning module, used to obtain the location information of the master base station;

[0035] The power supply module is electrically connected to the main control data acquisition module, the wireless transmission module and the positioning module respectively, and the main control data acquisition module and the positioning module are communicatively connected to the wireless transmission module respectively.

[0036] Further, the central base station comprises:

[0037] Power supply module, used for powering the data storage module, wireless transmission module and fusion module;

[0038] Data storage module, used to store acoustic data, meteorological data and main control parameters;

[0039] Wireless transmission module, used to receive acoustic data, meteorological data and main control parameters;

[0040] The fusion module is used to receive the location data of the acoustic base station, calculate the distance and azimuth, and perform multi-dimensional and multi-angle fusion processing based on the received acoustic data, meteorological data and main control parameters to obtain the acoustic propagation characteristics of the wind turbine in different directions, different unit operating states and different meteorological environments.

[0041] Further, the central base station performs the following operations:

[0042] The wind speed range measured by the meteorological base station includes the wind speed range corresponding to the start-up wind speed of the wind turbine to the wind speed range corresponding to the rated power. The wind speed is sampled at intervals of 0.5m / s, that is, several wind speed intervals are divided between the entire measured wind speed section, and the data is divided into each wind speed interval according to the wind speed size. Finally, the measurement results of the valid data points in each wind speed interval are obtained, and the average wind speed in the wind speed interval k is Calculated by formula (1):

[0043]

[0044] N is the number of measurements in the wind speed interval k; V j,k is the average wind speed in wind speed interval k within measurement period j.

[0045] Further, the central base station performs the following operations:

[0046] According to the location information of the acoustic base station and the location information of the main control base station, the position and angle of the acoustic base station relative to the wind turbine are calculated. The real-time position of the acoustic base station relative to the wind turbine is obtained by iterating the cabin azimuth angle data collected by the main control base station. The initial position of the cabin azimuth angle is the 0° direction of the acoustic measurement position, and the clockwise direction is 0-360°. When the wind speed changes, the cabin azimuth angle changes, and the pointing angle of the acoustic measurement position changes with the cabin azimuth angle. However, the 0° direction of the acoustic measurement position must always be kept consistent with the cabin azimuth angle, with an angle deviation of ±15°. The cabin azimuth angle is shown in the following formulas (2) to (3):

[0047]

[0048] θ WT is the cabin azimuth angle, The 0° pointing direction is used for acoustic measurement.

[0049] Further, the central base station performs the following operations:

[0050] The acoustic signal is subjected to time domain analysis, spectrum analysis and pitch analysis. The time domain analysis includes continuous time equivalence with a period of 10s, A weighting and Z weighting; the spectrum analysis obtains 0-10000Hz spectrum results, 1 / 3 octave band spectrum results, and 1 octave band spectrum results; the pitch analysis obtains the sound value and pitch audibility.

[0051] Further, the central base station performs the following operations:

[0052] To evaluate the relationship between ambient wind speed and acoustic characteristics of wind turbines, the wind speed data at a height of 10 m was used to correlate with the wind speed in the nacelle, thereby establishing the relationship between the operating status of the wind turbine, acoustic propagation and ambient wind speed. The calculation relationship between the wind speed at a height of 10 m and the wind speed in the nacelle is shown in formula (4):

[0053]

[0054] V 10 is the wind speed at a height of 10m, V H is the cabin wind speed, Z 0ref is the base roughness;

[0055] When correcting for background noise, if the difference between the total sound pressure level and the background noise is greater than 10dB, the effect of background noise on the noise source measurement is ignored. If the difference between the total sound pressure level and the background noise is less than 3dB, it is necessary to re-measure in a quiet environment. The background noise is processed through a 1 / 3 octave band. If the total noise level L is run on the same 1 / 3 octave band i, V,T,i,k Compared with the background noise level L V,B,i,kWhen it is at least 3 dB higher, the background corrected sound pressure level in 1 / 3 octave band i is calculated by formula (5):

[0056]

[0057] L V,c,i,k L is the A-weighted sound pressure level of background noise in 1 / 3 octave band i at wind speed k in the center of the interval; V,T,i,k L is the total noise sound pressure level in 1 / 3 octave band i at the wind speed k in the center of the interval; V,B,i,k is the background noise sound pressure level in 1 / 3 octave band i at wind speed k in the center of the interval.

[0058] A method for testing the acoustic directional propagation of a wind turbine generator set is implemented by calling the acoustic base station, the meteorological base station, the main control base station and the central base station in the above-mentioned wind turbine generator set acoustic directional propagation test system, and includes:

[0059] The acoustic base stations are respectively set at the corresponding positions of the upwind, left wind direction, downwind direction and right wind direction of the wind turbine, and the distance between each acoustic base station and the center of the wind turbine tower is not less than H+D / 2, where H is the hub height of the wind turbine and D is the rotor diameter of the wind turbine;

[0060] The meteorological base station is installed at a position D-2D away from the wind turbine and away from the rear of the wind turbine rotor. The height of the meteorological base station is not less than 10m. A wind speed sensor and a wind direction sensor are installed at a height of 10m of the meteorological base station, and the installation cross bars of the wind speed sensor and the wind direction sensor are perpendicular to the incoming wind direction.

[0061] The wind speed range measured by the meteorological base station includes the wind speed range corresponding to the start-up wind speed of the wind turbine to the wind speed range corresponding to the rated power. The wind speed is sampled at intervals of 0.5 m / s, that is, several wind speed intervals are divided between the entire measured wind speed section, and the data are divided into each wind speed interval according to the wind speed size. Finally, the measurement results of the valid data points in each wind speed interval are obtained, and the average wind speed V in the wind speed interval k is obtained. k , calculated by formula (6):

[0062]

[0063] N is the number of measurements in the wind speed interval k; V j,k is the average wind speed in measurement period j in wind speed interval k;

[0064] According to the location information of the acoustic base station and the location information of the main control base station, the position and angle of the acoustic base station relative to the wind turbine are calculated. The real-time position of the acoustic base station relative to the wind turbine is obtained by iterating the cabin azimuth angle data collected by the main control base station. The initial position of the cabin azimuth angle is the 0° direction of the acoustic measurement position, and the clockwise direction is 0-360°. When the wind speed changes, the cabin azimuth angle changes, and the pointing angle of the acoustic measurement position changes with the cabin azimuth angle. However, the 0° direction of the acoustic measurement position must always be kept consistent with the cabin azimuth angle, with an angle deviation of ±15°. The cabin azimuth angle is shown in the following formulas (7) to (8):

[0065]

[0066] θ WT is the cabin azimuth angle, 0° pointing direction for acoustic measurement;

[0067] The acoustic signal is subjected to time domain analysis, spectrum analysis and tone analysis. The time domain analysis includes continuous time equivalence with a period of 10s, A weighting and Z weighting; the spectrum analysis obtains 0-10000Hz spectrum results, 1 / 3 octave band spectrum results, and 1 octave band spectrum results; the tone analysis obtains the sound value and tone audibility;

[0068] To evaluate the relationship between ambient wind speed and acoustic characteristics of wind turbines, the wind speed data at a height of 10 m was used to correlate with the wind speed in the nacelle, thereby establishing the relationship between the operating status of the wind turbine, acoustic propagation and ambient wind speed. The calculation relationship between the wind speed at a height of 10 m and the wind speed in the nacelle is shown in formula (9):

[0069]

[0070] V 10 is the wind speed at a height of 10m, V H is the cabin wind speed, Z 0ref is the base roughness;

[0071] When correcting for background noise, if the difference between the total sound pressure level and the background noise is greater than 10dB, the effect of background noise on the noise source measurement is ignored. If the difference between the total sound pressure level and the background noise is less than 3dB, it is necessary to re-measure in a quiet environment. The background noise is processed through a 1 / 3 octave band. If the total noise level L is run on the same 1 / 3 octave band i, V,T,i,k Compared with the background noise level L V,B,i,k When it is at least 3 dB higher, the background corrected sound pressure level in 1 / 3 octave band i is calculated by formula (10):

[0072]

[0073] LV,c,i,k L is the A-weighted sound pressure level of background noise in 1 / 3 octave band i at wind speed k in the center of the interval; V,T,i,k L is the total noise sound pressure level in 1 / 3 octave band i at the wind speed k in the center of the interval; V,B,i,k is the background noise sound pressure level in 1 / 3 octave band i at wind speed k in the center of the interval.

[0074] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0075] (1) The present invention can effectively reveal the acoustic directional propagation law of wind turbines, and provide strong support for the acoustic design research and noise reduction engineering of wind turbines.

[0076] (2) The present invention can simultaneously monitor the meteorological environment that affects acoustic propagation, the unit main control parameters that affect blade aeroacoustics, and other information, and calculate the noise variation law and influencing factors of the wind turbine unit from multiple physical perspectives of the sound source and the sound propagation environment.

[0077] (3) The linear interpolation method is used to correspond the wind speed and noise measurements of the wind turbine nacelle with the meteorological environment wind speed and noise measurements, effectively representing the relationship between the main control operation of the wind turbine, the atmospheric environment and the directional acoustic characteristics.

[0078] (4) The wind turbine acoustic directivity propagation test system of the present invention is provided with a positioning module and collects cabin azimuth information, which can accurately locate the angle relationship of the position related to the directivity.

[0079] (5) The acoustic signal includes A-weighted sound pressure level and Z-weighted sound pressure level, which evaluate the acoustic impact from the perspective of acoustic frequency response to the human ear and low frequency. From the spectrum perspective, it includes 0-10000Hz narrowband spectrum, 1 / 3 octave band spectrum, and 1 octave band spectrum, which provide data support for spectrum evaluation of different methods and evaluate the directional acoustic characteristics more finely from the spectrum perspective. By adding tone audibility and sound value measurement, the tone characteristics are evaluated from the perspective of different operating conditions and directionality of wind turbines, and the noise directivity of wind turbines is evaluated more comprehensively.

[0080] (6) In the wind turbine acoustic directional propagation test system of the present invention, each acquisition base station module is integrated, and the test site installation is simple and easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] Figure 1 Schematic diagram of base station signal transmission in the wind turbine acoustic directional propagation test system.

[0082] Figure 2 This is a schematic diagram of the base station structure of the wind turbine acoustic directional propagation test system.

[0083] Figure 3 Schematic diagram of the installation location of the acoustic base station.

[0084] Figure 4 This is a schematic diagram of the installation location of the meteorological base station.

[0085] Figure 5 Schematic diagram of the layout of the wind turbine acoustic directional propagation test system.

[0086] Figure 6 This is the data transmission topology diagram of the wind turbine acoustic directivity propagation test system.

[0087] Figure 7 This is a schematic diagram of the data correspondence of the wind turbine acoustic directivity propagation test system. DETAILED DESCRIPTION

[0088] The present invention will be further described below in conjunction with specific embodiments.

[0089] Example 1

[0090] See also Figure 1 to Figure 2 As shown, the wind turbine acoustic directional propagation test system provided in this embodiment includes:

[0091] 1) Acoustic base station 2, used to collect and transmit acoustic data, the acoustic base station 2 is respectively set at the corresponding positions of the upwind direction, left wind direction, downwind direction and right wind direction of the wind turbine, and measures the acoustic characteristics of different angles when the wind turbine rotor rotates, and each acoustic base station 2 is not less than H+D / 2 from the center of the wind turbine tower, where H is the height of the wind turbine hub and D is the diameter of the wind turbine rotor. The acoustic base station 2 includes:

[0092] An acoustic data acquisition module 8, used for collecting acoustic data;

[0093] A power supply module 9, used for supplying power to the acoustic data acquisition module 8, the wireless transmission module 10 and the positioning module 11;

[0094] A wireless transmission module 10, used to transmit acoustic data to the central base station 4;

[0095] A positioning module 11, used to obtain the location information of the acoustic base station 2;

[0096] The power supply module 9 is electrically connected to the acoustic data acquisition module 8, the wireless transmission module 10 and the positioning module 11 respectively, and the acoustic data acquisition module 8 and the positioning module 11 are communicatively connected to the wireless transmission module 10 respectively;

[0097] See also Figure 3 and Figure 5As shown, the acoustic base station 2 is installed with a sound pressure sensor, an acoustic calibrator and a bracket 19, and the bracket 19 is installed with a sound level meter 20 and a windbreak ball, and the installation height is 1.2 meters to 1.5 meters. The sound level meter 20 points to the center of the wind wheel to measure the upwind direction, left wind direction, right wind direction and downwind direction of the wind turbine 25, a total of 4 required positions. The sound pressure sensor, acoustic calibrator and sound level meter 20 are respectively communicated with the acoustic data acquisition module.

[0098] 2) Meteorological base station 1, used to collect and transmit meteorological data, see Figures 4 to 5 As shown, the meteorological base station 1 is installed within the range of D-2D from the vertical ground position of the center of the hub of the wind turbine 25 and avoids the position of +6° behind the wind rotor of the wind turbine 25 to avoid being affected by the wake of the wind turbine 25. The meteorological base station 1 includes:

[0099] Meteorological data collection module 5, used for collecting meteorological data;

[0100] A power supply module 6 is used to supply power to the meteorological data acquisition module 5 and the wireless transmission module 7;

[0101] A wireless transmission module 7, used to transmit meteorological data to the central base station 4;

[0102] The power supply module 6 is electrically connected to the meteorological data acquisition module 5 and the wireless transmission module 7 respectively, and the meteorological data acquisition module 5 is communicatively connected to the wireless transmission module 7;

[0103] A meteorological wind tower is installed at the meteorological base station 1, and a wind speed sensor 23, a wind direction sensor 24, a temperature sensor 21 and an air pressure sensor 22 are installed on the meteorological wind tower. The wind speed sensor 23, the wind direction sensor 24, the temperature sensor 21 and the air pressure sensor 22 are respectively connected to the meteorological data acquisition module 5 for communication; the height of the meteorological wind tower is not less than 10m, and the wind speed sensor 23 and the wind direction sensor 24 are installed at a height of 10m of the meteorological wind tower, and the installation cross bars of the wind speed sensor 23 and the wind direction sensor 24 are perpendicular to the incoming wind direction; the temperature sensor 21 and the air pressure sensor 22 are installed at the meteorological wind tower, and the installation height is not less than 1.5m.

[0104] 3) A main control base station 3, used for collecting and transmitting the main control parameters of the wind turbine set, the main control base station is arranged at the main control structure of the wind turbine set 25, that is, at the vertical ground position of the hub center at the bottom of the tower of the wind turbine set 25, the main control parameters include power, speed, blade angle, cabin wind speed and cabin azimuth, the main control base station 3 includes:

[0105] A main control data acquisition module 12 is used to collect the main control parameters of the wind turbine generator set;

[0106] The power supply module 13 is used to supply power to the main control data acquisition module 12, the wireless transmission module 14 and the positioning module 15;

[0107] A wireless transmission module 14, used to transmit the master control parameters to the central base station 4;

[0108] The positioning module 15 is used to obtain the location information of the master control base station 3;

[0109] The power supply module 13 is electrically connected to the main control data acquisition module 12 , the wireless transmission module 14 and the positioning module 15 , respectively. The main control data acquisition module 12 and the positioning module 15 are communicatively connected to the wireless transmission module 14 , respectively.

[0110] 4) Central base station 4, used to receive acoustic data, meteorological data and main control parameters, and perform multi-dimensional and multi-angle fusion processing based on the received acoustic data, meteorological data and main control parameters to obtain the acoustic propagation characteristics of wind turbines in different directions, different unit operating states and different meteorological environments, including:

[0111] A power supply module 17, used for supplying power to the data storage module, the wireless transmission module and the fusion module;

[0112] A data storage module 16, used to store acoustic data, meteorological data and main control parameters;

[0113] A wireless transmission module 18, for receiving acoustic data, meteorological data and main control parameters;

[0114] The fusion module is used to receive the location data of the acoustic base station, calculate the distance and azimuth, and perform multi-dimensional and multi-angle fusion processing based on the received acoustic data, meteorological data and main control parameters to obtain the acoustic propagation characteristics of the wind turbine in different directions, different unit operating states and different meteorological environments.

[0115] The central base station specifically performs the following operations:

[0116] The wind speed range measured by the meteorological base station includes the wind speed range corresponding to the start-up wind speed of the wind turbine to the wind speed range corresponding to the rated power. The wind speed is sampled at intervals of 0.5m / s, and the Bin interval is processed, that is, several wind speed intervals are divided between the entire measured wind speed section, and the data is divided into each wind speed interval according to the wind speed size.

[0117] Get the measurement results of valid data points in each wind speed interval, and the average wind speed in wind speed interval k Calculated by formula (6):

[0118]

[0119] N is the number of measurements in the wind speed interval k; V j,k is the average wind speed in wind speed interval k within measurement period j.

[0120] See also Figure 5 As shown, the entire system is located in a flat terrain with no interference from other noise sources around. If there are other sounds around and they cannot be avoided, the test data should be screened and filtered to avoid interference from occasional environmental sound sources on the test results.

[0121] When the wind turbine rotor is directly in front of the north direction, the nacelle azimuth is 0°, and the azimuth is 0°-359° clockwise when looking down. The required acoustic test points are located in the upwind, right wind direction, downwind direction, and left wind direction of the unit. It is preferred that the acoustic test points are distributed at an average angle or arranged according to the focus position, such as Figure 5 As shown. When the wind direction changes, the cabin azimuth changes immediately. For example, when the cabin azimuth is 90°, the data obtained at the 90° point is the result when the unit is pointing directly upwind, and the data obtained at the 270° point is the result when the unit is pointing directly downwind. The data obtained at each test point is stored in a separate bin according to the change in cabin azimuth. The data is valid when the cabin azimuth is stable for 10 seconds and the angle deviation from the test point is within ±5°, otherwise it is considered invalid data.

[0122] According to the location information of the acoustic base station and the location information of the main control base station, the position and angle of the acoustic base station relative to the wind turbine are calculated. The real-time position of the acoustic base station relative to the wind turbine is obtained by iterating the cabin azimuth angle data collected by the main control base station. The initial position of the cabin azimuth angle is the 0° direction of the acoustic measurement position, and the clockwise direction is 0-360°. When the wind speed changes, the cabin azimuth angle changes, and the pointing angle of the acoustic measurement position changes with the cabin azimuth angle. However, the 0° direction of the acoustic measurement position must always be kept consistent with the cabin azimuth angle, with an angle deviation of ±15°. The cabin azimuth angle is shown in the following formulas (7) to (8):

[0123]

[0124] θ WT is the cabin azimuth angle, 0° pointing direction for acoustic measurement;

[0125] The acoustic signal is subjected to time domain analysis, spectrum analysis and tone analysis. The time domain analysis includes continuous time equivalence with a period of 10s, A weighting and Z weighting; the spectrum analysis obtains 0-10000Hz spectrum results, 1 / 3 octave band spectrum results, and 1 octave band spectrum results; the tone analysis obtains the sound value and tone audibility;

[0126] To evaluate the relationship between ambient wind speed and acoustic characteristics of wind turbines, the wind speed data at a height of 10 m was used to correlate with the wind speed in the nacelle, thereby establishing the relationship between the operating status of the wind turbine, acoustic propagation and ambient wind speed. The calculation relationship between the wind speed at a height of 10 m and the wind speed in the nacelle is shown in formula (9):

[0127]

[0128] V 10 is the wind speed at a height of 10m, V H is the cabin wind speed, Z 0ref is the base roughness;

[0129] When correcting for background noise, if the difference between the total sound pressure level and the background noise is greater than 10dB, the effect of background noise on the noise source measurement is ignored. If the difference between the total sound pressure level and the background noise is less than 3dB, it is necessary to re-measure in a quiet environment. The background noise is processed through a 1 / 3 octave band. If the total noise level L is run on the same 1 / 3 octave band i, V,T,i,k Compared with the background noise level L V,B,i,k When it is at least 3 dB higher, the background corrected sound pressure level in 1 / 3 octave band i is calculated by formula (10):

[0130]

[0131] L V,c,i,k L is the A-weighted sound pressure level of background noise in 1 / 3 octave band i at wind speed k in the center of the interval; V,T,i,k L is the total noise sound pressure level in 1 / 3 octave band i at the wind speed k in the center of the interval; V,B,i,k is the background noise sound pressure level in 1 / 3 octave band i at wind speed k in the center of the interval.

[0132] Example 2

[0133] See also Figure 6 to Figure 7 As shown, this embodiment discloses a method for testing the acoustic directivity propagation of a wind turbine. The method is implemented by calling the acoustic base station, the meteorological base station, the master control base station and the central base station in the acoustic directivity propagation test system for a wind turbine described in Example 1, and includes:

[0134] The acoustic base stations are respectively set at the corresponding positions of the upwind, left wind direction, downwind direction and right wind direction of the wind turbine, and the distance between each acoustic base station and the center of the wind turbine tower is not less than H+D / 2, where H is the hub height of the wind turbine and D is the rotor diameter of the wind turbine;

[0135] The meteorological base station is installed at a position D-2D away from the wind turbine and away from the rear of the wind turbine rotor. The height of the meteorological base station is not less than 10m. A wind speed sensor and a wind direction sensor are installed at a height of 10m of the meteorological base station, and the installation cross bars of the wind speed sensor and the wind direction sensor are perpendicular to the incoming wind direction.

[0136] The wind speed range measured by the meteorological base station includes the wind speed range corresponding to the start-up wind speed of the wind turbine to the wind speed range corresponding to the rated power. The wind speed is sampled at intervals of 0.5m / s, that is, several wind speed intervals are divided between the entire measured wind speed section, and the data is divided into each wind speed interval according to the wind speed size. Finally, the measurement results of the valid data points in each wind speed interval are obtained, and the average wind speed in the wind speed interval k is Calculated by formula (6):

[0137]

[0138] N is the number of measurements in the wind speed interval k; V j,k is the average wind speed in measurement period j in wind speed interval k;

[0139] When the wind turbine rotor is directly in front of the north direction, the nacelle azimuth is 0°, and the azimuth is 0°-359° clockwise when looking down. The required acoustic test points are located in the upwind, right wind direction, downwind direction, and left wind direction of the unit. It is preferred that the acoustic test points are distributed at an average angle or arranged according to the focus position, such as Figure 5 As shown. When the wind direction changes, the cabin azimuth changes immediately. For example, when the cabin azimuth is 90°, the data obtained at the 90° point is the result when the unit is pointing directly upwind, and the data obtained at the 270° point is the result when the unit is pointing directly downwind. The data obtained at each test point is stored in a separate bin according to the change in cabin azimuth. The data is valid when the cabin azimuth is stable for 10 seconds and the angle deviation from the test point is within ±5°, otherwise it is considered invalid data.

[0140] According to the location information of the acoustic base station and the location information of the main control base station, the position and angle of the acoustic base station relative to the wind turbine are calculated. The real-time position of the acoustic base station relative to the wind turbine is obtained by iterating the cabin azimuth angle data collected by the main control base station. The initial position of the cabin azimuth angle is the 0° direction of the acoustic measurement position, and the clockwise direction is 0-360°. When the wind speed changes, the cabin azimuth angle changes, and the pointing angle of the acoustic measurement position changes with the cabin azimuth angle. However, the 0° direction of the acoustic measurement position must always be kept consistent with the cabin azimuth angle, with an angle deviation of ±15°. The cabin azimuth angle is shown in the following formulas (7) to (8):

[0141]

[0142] θ WT is the cabin azimuth angle, 0° pointing direction for acoustic measurement;

[0143] The acoustic signal is subjected to time domain analysis, spectrum analysis and tone analysis. The time domain analysis includes continuous time equivalence with a period of 10s, A weighting and Z weighting; the spectrum analysis obtains 0-10000Hz spectrum results, 1 / 3 octave band spectrum results, and 1 octave band spectrum results; the tone analysis obtains the sound value and tone audibility;

[0144] To evaluate the relationship between ambient wind speed and acoustic characteristics of wind turbines, the wind speed data at a height of 10 m was used to correlate with the wind speed in the nacelle, thereby establishing the relationship between the operating status of the wind turbine, acoustic propagation and ambient wind speed. The calculation relationship between the wind speed at a height of 10 m and the wind speed in the nacelle is shown in formula (9):

[0145]

[0146] V 10 is the wind speed at a height of 10m, V H is the cabin wind speed, Z 0ref is the base roughness;

[0147] When correcting for background noise, if the difference between the total sound pressure level and the background noise is greater than 10dB, the effect of background noise on the noise source measurement is ignored. If the difference between the total sound pressure level and the background noise is less than 3dB, it is necessary to re-measure in a quiet environment. The background noise is processed through a 1 / 3 octave band. If the total noise level L is run on the same 1 / 3 octave band i, V,T,i,k Compared with the background noise level L V,B,i,k When it is at least 3 dB higher, the background corrected sound pressure level in 1 / 3 octave band i is calculated by formula (10):

[0148]

[0149] L V,c,i,k L is the A-weighted sound pressure level of background noise in 1 / 3 octave band i at wind speed k in the center of the interval; V,T,i,k L is the total noise sound pressure level in 1 / 3 octave band i at the wind speed k in the center of the interval; V,B,i,k is the background noise sound pressure level in 1 / 3 octave band i at wind speed k in the center of the interval.

[0150] The embodiments described above are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Therefore, all changes made according to the shape and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A wind turbine acoustic directional propagation test system, characterized in that: include: Acoustic base stations, used to collect and transmit acoustic data, the acoustic base stations are respectively arranged at corresponding positions of the upwind direction, left wind direction, downwind direction and right wind direction of the wind turbine, and the distance between each acoustic base station and the center of the wind turbine tower is not less than H+D / 2, where H is the hub height of the wind turbine and D is the rotor diameter of the wind turbine; A meteorological base station, used for collecting and transmitting meteorological data, wherein the meteorological base station is installed at a position D-2D away from the wind turbine and away from the rear of the wind turbine rotor; A main control base station, used for collecting and transmitting the main control parameters of the wind turbine set, the main control base station is arranged at the main control structure of the wind turbine set, the main control parameters include power, speed, blade angle, cabin wind speed and cabin azimuth; The central base station is used to receive acoustic data, meteorological data and main control parameters, and perform multi-dimensional and multi-angle fusion processing based on the received acoustic data, meteorological data and main control parameters to obtain the acoustic propagation characteristics of wind turbines in different directions, different unit operating states and different meteorological environments.

2. A wind turbine acoustic directional propagation test system according to claim 1, characterized in that: The acoustic base station comprises: An acoustic data acquisition module, used for collecting acoustic data; Power supply module, used for powering the acoustic data acquisition module, wireless transmission module and positioning module; A wireless transmission module for transmitting acoustic data to a central base station; A positioning module, used to obtain the location information of the acoustic base station; The power supply module is electrically connected to the acoustic data acquisition module, the wireless transmission module and the positioning module respectively, and the acoustic data acquisition module and the positioning module are communicatively connected to the wireless transmission module respectively; A sound pressure sensor, an acoustic calibrator and a bracket are installed at the acoustic base station, a sound level meter and a windproof ball are installed on the bracket, and the sound pressure sensor, the acoustic calibrator and the sound level meter are respectively connected to the acoustic data acquisition module for communication.

3. A wind turbine acoustic directional propagation test system according to claim 1, characterized in that: The meteorological base station comprises: Meteorological data collection module, used for collecting meteorological data; Power supply module, used for powering the meteorological data acquisition module and the wireless transmission module; A wireless transmission module for transmitting meteorological data to a central base station; The power supply module is electrically connected to the meteorological data acquisition module and the wireless transmission module respectively, and the meteorological data acquisition module is communicatively connected to the wireless transmission module; A meteorological wind tower is installed at the meteorological base station. A wind speed sensor, a wind direction sensor, a temperature sensor and an air pressure sensor are installed on the meteorological wind tower. The wind speed sensor, wind direction sensor, temperature sensor and air pressure sensor are respectively connected to the meteorological data acquisition module for communication.

4. A wind turbine acoustic directional propagation test system according to claim 1, characterized in that: The master control base station comprises: Main control data acquisition module, used to collect main control parameters of wind turbines; Power supply module, used for powering the main control data acquisition module, wireless transmission module and positioning module; A wireless transmission module, used to transmit the master control parameters to the central base station; Positioning module, used to obtain the location information of the master base station; The power supply module is electrically connected to the main control data acquisition module, the wireless transmission module and the positioning module respectively, and the main control data acquisition module and the positioning module are communicatively connected to the wireless transmission module respectively.

5. The wind turbine acoustic directional propagation test system according to claim 1, characterized in that: The central base station comprises: Power supply module, used for powering the data storage module, wireless transmission module and fusion module; Data storage module, used to store acoustic data, meteorological data and main control parameters; Wireless transmission module, used to receive acoustic data, meteorological data and main control parameters; The fusion module is used to receive the location data of the acoustic base station, calculate the distance and azimuth, and perform multi-dimensional and multi-angle fusion processing based on the received acoustic data, meteorological data and main control parameters to obtain the acoustic propagation characteristics of the wind turbine in different directions, different unit operating states and different meteorological environments.

6. The wind turbine acoustic directional propagation test system according to claim 1, characterized in that: The central base station performs the following operations: The wind speed range measured by the meteorological base station includes the wind speed range corresponding to the start-up wind speed of the wind turbine to the wind speed range corresponding to the rated power. The wind speed is sampled at intervals of 0.5m / s, that is, several wind speed intervals are divided between the entire measured wind speed section, and the data is divided into each wind speed interval according to the wind speed size. Finally, the measurement results of the valid data points in each wind speed interval are obtained, and the average wind speed in the wind speed interval k is Calculated by formula (1): N is the number of measurements in the wind speed interval k; V j,k is the average wind speed in wind speed interval k within measurement period j.

7. A wind turbine acoustic directional propagation test system according to claim 1, characterized in that: The central base station performs the following operations: According to the location information of the acoustic base station and the location information of the main control base station, the position and angle of the acoustic base station relative to the wind turbine are calculated. The real-time position of the acoustic base station relative to the wind turbine is obtained by iterating the cabin azimuth angle data collected by the main control base station. The initial position of the cabin azimuth angle is the 0° direction of the acoustic measurement position, and the clockwise direction is 0-360°. When the wind speed changes, the cabin azimuth angle changes, and the pointing angle of the acoustic measurement position changes with the cabin azimuth angle. However, the 0° direction of the acoustic measurement position must always be kept consistent with the cabin azimuth angle, with an angle deviation of ±15°. The cabin azimuth angle is shown in the following formulas (2) to (3): θ WT is the cabin azimuth angle, The 0° pointing direction is used for acoustic measurement.

8. The wind turbine acoustic directional propagation test system according to claim 1, characterized in that: The central base station performs the following operations: The acoustic signal is subjected to time domain analysis, spectrum analysis and pitch analysis. The time domain analysis includes continuous time equivalence with a period of 10s, A weighting and Z weighting; the spectrum analysis obtains 0-10000Hz spectrum results, 1 / 3 octave band spectrum results, and 1 octave band spectrum results; the pitch analysis obtains the sound value and pitch audibility.

9. The wind turbine acoustic directional propagation test system according to claim 1, characterized in that: The central base station performs the following operations: To evaluate the relationship between ambient wind speed and acoustic characteristics of wind turbines, the wind speed data at a height of 10 m was used to correlate with the wind speed in the nacelle, thereby establishing the relationship between the operating status of the wind turbine, acoustic propagation and ambient wind speed. The calculation relationship between the wind speed at a height of 10 m and the wind speed in the nacelle is shown in formula (4): V 10 is the wind speed at a height of 10m, V H is the cabin wind speed, Z 0ref is the base roughness; When correcting for background noise, if the difference between the total sound pressure level and the background noise is greater than 10dB, the effect of background noise on the noise source measurement is ignored. If the difference between the total sound pressure level and the background noise is less than 3dB, it is necessary to re-measure in a quiet environment. The background noise is processed through a 1 / 3 octave band. If the total noise level L is run on the same 1 / 3 octave band i, V,T,i,k Compared with the background noise level L V,B,i,k When it is at least 3 dB higher, the background corrected sound pressure level in 1 / 3 octave band i is calculated by formula (5): L V,c,i,k L is the A-weighted sound pressure level of background noise in 1 / 3 octave band i at wind speed k in the center of the interval; V,T,i,k L is the total noise sound pressure level in 1 / 3 octave band i at the wind speed k in the center of the interval; V,B,i,k is the background noise sound pressure level in 1 / 3 octave band i at wind speed k in the center of the interval.

10. A method for testing the acoustic directional propagation of a wind turbine, characterized in that: The method is implemented by calling the acoustic base station, the meteorological base station, the main control base station and the central base station in the wind turbine acoustic directivity propagation test system according to any one of claims 1 to 9, and includes: The acoustic base stations are respectively set at the corresponding positions of the upwind, left wind direction, downwind direction and right wind direction of the wind turbine, and the distance between each acoustic base station and the center of the wind turbine tower is not less than H+D / 2, where H is the hub height of the wind turbine and D is the rotor diameter of the wind turbine; The meteorological base station is installed at a position D-2D away from the wind turbine and away from the rear of the wind turbine rotor. The height of the meteorological base station is not less than 10m. A wind speed sensor and a wind direction sensor are installed at a height of 10m of the meteorological base station, and the installation cross bars of the wind speed sensor and the wind direction sensor are perpendicular to the incoming wind direction. The wind speed range measured by the meteorological base station includes the wind speed range corresponding to the start-up wind speed of the wind turbine to the wind speed range corresponding to the rated power. The wind speed is sampled at intervals of 0.5m / s, that is, several wind speed intervals are divided between the entire measured wind speed section, and the data is divided into each wind speed interval according to the wind speed size. Finally, the measurement results of the valid data points in each wind speed interval are obtained, and the average wind speed in the wind speed interval k is Calculated by formula (6): N is the number of measurements in the wind speed interval k; V j,k is the average wind speed in measurement period j in wind speed interval k; According to the location information of the acoustic base station and the location information of the main control base station, the position and angle of the acoustic base station relative to the wind turbine are calculated. The real-time position of the acoustic base station relative to the wind turbine is obtained by iterating the cabin azimuth angle data collected by the main control base station. The initial position of the cabin azimuth angle is the 0° direction of the acoustic measurement position, and the clockwise direction is 0-360°. When the wind speed changes, the cabin azimuth angle changes, and the pointing angle of the acoustic measurement position changes with the cabin azimuth angle. However, the 0° direction of the acoustic measurement position must always be kept consistent with the cabin azimuth angle, with an angle deviation of ±15°. The cabin azimuth angle is shown in the following formulas (7) to (8): θ WT is the cabin azimuth angle, 0° pointing direction for acoustic measurement; The acoustic signal is subjected to time domain analysis, spectrum analysis and tone analysis. The time domain analysis includes continuous time equivalence with a period of 10s, A weighting and Z weighting; the spectrum analysis obtains 0-10000Hz spectrum results, 1 / 3 octave band spectrum results, and 1 octave band spectrum results; the tone analysis obtains the sound value and tone audibility; To evaluate the relationship between ambient wind speed and acoustic characteristics of wind turbines, the wind speed data at a height of 10 m was used to correlate with the wind speed in the nacelle, thereby establishing the relationship between the operating status of the wind turbine, acoustic propagation and ambient wind speed. The calculation relationship between the wind speed at a height of 10 m and the wind speed in the nacelle is shown in formula (9): V 10 is the wind speed at a height of 10m, V H is the cabin wind speed, Z 0ref is the base roughness; When correcting for background noise, if the difference between the total sound pressure level and the background noise is greater than 10dB, the effect of background noise on the noise source measurement is ignored. If the difference between the total sound pressure level and the background noise is less than 3dB, it is necessary to re-measure in a quiet environment. The background noise is processed through a 1 / 3 octave band. If the total noise level L is run on the same 1 / 3 octave band i, V,T,i,k Compared with the background noise level L V,B,i,k When it is at least 3 dB higher, the background corrected sound pressure level in 1 / 3 octave band i is calculated by formula (10): L V,c,i,k L is the A-weighted sound pressure level of background noise in 1 / 3 octave band i at wind speed k in the center of the interval; V,T,i,k L is the total noise sound pressure level in 1 / 3 octave band i at the wind speed k in the center of the interval; V,B,i,k is the background noise sound pressure level in 1 / 3 octave band i at wind speed k in the center of the interval.

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