Wind measurement device, wind measurement method, and wind measurement program

Abstract

A wind measurement device (10) is provided with ultrasonic sensors (11a, 11b, 11c, 11d), a wind microcomputer (18), and a base part (15). The ultrasonic sensors (11b, 11d) receive ultrasonic waves emitted from the ultrasonic sensors (11a, 11c). A measurement region (A1) is provided between the ultrasonic sensors (11a, 11b, 11c, 11d). The wind microcomputer (18) measures the wind speed in the measurement region (A1) on the basis of a change in reception timings of the ultrasonic waves. The base part (15) is provided in the vicinity of the ultrasonic sensors (11a, 11b, 11c, 11d), and serves as resistance against wind toward the measurement region (A1). The wind microcomputer (18) corrects a measurement result using a correction coefficient that changes in accordance with a direction of the wind, so as to eliminate an influence of the base part (15) on the measurement of the wind in the measurement region (A1).

Description

Wind measurement device, wind measurement method, and wind measurement program

[0001] The present invention relates to a wind measurement device, a wind measurement method, and a wind measurement program for measuring wind speed and direction.

[0002] In recent years, wind speed sensors have been installed as weather sensors to measure wind speed and direction outdoors. For example, Patent Document 1 discloses a wind speed and direction sensor using ultrasonic waves. This wind speed and direction sensor includes a transmitter that emits ultrasonic waves, a first receiver that receives the ultrasonic waves emitted from the transmitter and detects their arrival and reflects the ultrasonic waves, and a second receiver that receives the ultrasonic waves reflected by the first receiver and detects their arrival. The direction and / or speed of airflow between the transmitter and the second receiver and the first receiver are calculated based on the propagation time of the ultrasonic waves from the transmitter to the first receiver and the propagation time of the ultrasonic waves from the first receiver to the second receiver.

[0003] JP 2013-79891 A

[0004] However, the above-mentioned conventional wind speed and direction sensor has the following problem: The wind speed and direction sensor disclosed in the above publication has a problem in that errors are likely to occur in measuring wind speed and direction if a foreign object or the like is present in the measurement area between the wave transmitter that emits ultrasonic waves and the first and second wave receivers that receive the ultrasonic waves emitted from the wave transmitter.

[0005] In particular, if such foreign objects are obstacles fixedly placed near the transmitter and receiver, they may have a significant effect on measurements depending on the wind direction.An object of the present invention is to provide a wind measurement device, a wind measurement method, and a wind measurement program that are capable of measuring wind speed with high accuracy by eliminating the effects of obstacles placed near the transmitter that emits ultrasonic waves and the receiver that receives the emitted ultrasonic waves.

[0006] (Means for solving the problem) A wind measurement device according to a first aspect of the present invention is a wind measurement device that measures wind speed and direction, and includes an emitter, a receiver, a measurement area, the measurement unit, an obstacle, and a correction unit. The emitter emits ultrasonic waves in a predetermined direction. The receiver receives the ultrasonic waves emitted from the emitter. The measurement area is located between the emitter and the receiver. The measurement unit measures wind speed and direction in the measurement area based on changes in the reception timing of the ultrasonic waves received by the receiver. The obstacle is located near the emitter and the receiver, and can cause resistance to wind heading toward the measurement area. The correction unit corrects the measurement results of the measurement unit using a correction coefficient that varies depending on the wind direction, so as to eliminate the influence of the obstacle on wind measurement in the measurement area.

[0007] Here, for example, in order to eliminate the influence of obstacles that are disposed near the emitter that emits ultrasonic waves and the receiver that receives ultrasonic waves and that may cause resistance to wind toward the measurement area, the wind speed value measured in the measurement area is corrected using a correction coefficient that varies depending on the wind direction. Here, the emitter and receiver may function as the emitter and receiver using, for example, a single ultrasonic sensor, or dedicated components may be used as the emitter and receiver.

[0008] The ultrasonic waves emitted from the emitter may be received directly by the receiver, or may be received, for example, via a reflecting surface provided opposite the emitter and receiver. The emitter and receiver used as a pair may be provided in two sets, one set, or three or more sets. The measurement unit measures wind speed and direction by detecting a difference (phase difference) in the reception timing, for example, based on the timing at which the ultrasonic waves emitted from the emitter are received by the receiver in a windless state.

[0009] The obstacles include, for example, irregularities, columnar members, etc., located near the transmitter and receiver. This allows the measurement results to be corrected using different correction coefficients depending on the wind direction, even if the influence of obstacles located near the transmitter and receiver changes depending on the wind direction. As a result, it is possible to measure wind speed with high accuracy by eliminating the influence of obstacles located near the transmitter that emits ultrasonic waves and the receiver that receives the emitted ultrasonic waves.

[0010] A second aspect of the present invention is a wind measurement device according to the first aspect of the present invention, wherein the correction unit obtains a correction coefficient from the results of a simulation showing the flow of wind in the measurement area when the direction of the wind toward the measurement area is changed. As a result, even if the influence of obstacles placed near the emission unit and the reception unit changes depending on the wind direction, the correction coefficient set from the results of the simulation is used to correct the measurement value according to the wind direction, making it possible to measure wind speed and direction with high accuracy while eliminating the influence of obstacles.

[0011] A wind measurement device according to a third aspect of the present invention is the wind measurement device according to the second aspect of the present invention, further comprising a memory unit for storing correction coefficients obtained from the results of simulations. As a result, by correcting the measurement values ​​obtained by the measurement unit using the correction coefficients stored in the memory unit, it is possible to eliminate the influence of obstacles that change depending on the wind direction and measure wind speed and direction with high accuracy.

[0012] A fourth aspect of the present invention is the wind measurement device of the third aspect, wherein the memory unit stores correction coefficients at multiple levels. As a result, even if the magnitude of the influence of obstacles varies depending on the wind strength (wind speed), for example, the measurement value can be corrected using a correction coefficient set according to the wind strength, thereby obtaining a more accurate measurement value.

[0013] A fifth aspect of the present invention is the wind measurement device of the fourth aspect of the present invention, wherein the correction coefficient is set to a plurality of different values ​​for each predetermined wind direction, thereby making it possible to correct the measurement value using different correction coefficients, for example, correction coefficients for (0 degrees, 90 degrees, 180 degrees, 270 degrees) and correction coefficients for (45 degrees, 135 degrees, 225 degrees, 315 degrees).

[0014] A sixth aspect of the present invention is the wind measurement device of the fourth or fifth aspect of the present invention, in which the correction coefficient is set in multiple stages depending on the position of the obstacle, thereby making it possible to correct the measurement value using different correction coefficients depending on, for example, the position of the obstacle (including the number of obstacles).

[0015] A seventh aspect of the present invention is the wind measurement device of the first or second aspect of the present invention, further comprising a reflecting surface that reflects ultrasonic waves emitted from the emitting unit toward the receiving unit. As a result, the ultrasonic waves irradiated from the emitting unit are received by the receiving unit via the reflecting surface, and wind speed and wind direction can be measured according to the deviation from the reception timing at the receiving unit in a windless state.

[0016] The wind measurement device according to an eighth aspect of the present invention is the wind measurement device according to the seventh aspect of the present invention, wherein the emitting unit and the receiving unit are arranged symmetrically about the central axis of the reflecting surface, so that the ultrasonic waves emitted from the emitting unit can be efficiently received by the receiving unit.

[0017] A wind measurement device according to a ninth aspect of the present invention is the wind measurement device according to the first or second aspect of the present invention, in which two pairs of emitters and receivers are provided. As a result, for example, by arranging the two pairs of emitters and receivers at 90 degrees to each other, it is possible to accurately measure the speed and direction of wind blowing into the measurement area from all directions of 360 degrees.

[0018] A wind measurement device according to a tenth aspect of the present invention is the wind measurement device according to the first or second aspect of the present invention, wherein the emitter and receiver are a pair of ultrasonic sensors that are switchable between each other. This allows a highly accurate wind measurement device to be configured with a simple configuration by using a single ultrasonic sensor and switching between its functions as the emitter and receiver.

[0019] A wind measurement device according to an eleventh aspect of the present invention is the wind measurement device according to the first or second aspect of the present invention, wherein the obstacle is a base provided on a first surface on which the emitting unit and the receiving unit are arranged and protruding from the first surface while supporting the emitting unit and the receiving unit. As a result, even if the base supporting the emitting unit and the receiving unit is configured to cause resistance to wind toward the measurement area, it is possible to measure wind speed and wind direction with high accuracy by correcting the measurement value using a correction coefficient that differs depending on the wind direction.

[0020] A wind measurement device according to a twelfth aspect of the present invention is the wind measurement device according to the eleventh aspect of the present invention, further comprising a reflecting surface that reflects ultrasonic waves emitted from the emitting portion toward the receiving portion. The base supports the emitting portion and the receiving portion at an angle with respect to the first surface so that the ultrasonic waves are emitted from the emitting portion at an angle with respect to the first surface and received by the receiving portion via the reflecting surface at an angle with respect to the first surface. This allows the reflection of the ultrasonic waves emitted from the emitting portion at an angle with respect to the reflecting surface to be efficiently received by the receiving portion.

[0021] A thirteenth aspect of the present invention is the wind measurement device of the first or second aspect of the present invention, wherein the obstacles are pillar members erected on the first surface on which the emitting unit and the receiving unit are arranged and provided around the measurement area. As a result, even if the pillar members create resistance to the wind heading toward the measurement area in a wind measurement device incorporated in a weather sensor having multiple measurement targets, it is possible to measure wind speed and direction with high accuracy by correcting the measurement values ​​using different correction coefficients depending on the wind direction.

[0022] A fourteenth aspect of the present invention provides a wind measurement method for measuring wind speed and direction, comprising an emission step, a reception step, a measurement step, and a correction step. In the emission step, ultrasonic waves are emitted from an emission unit in a predetermined direction. In the reception step, the ultrasonic waves emitted in the emission step are received by a reception unit. In the measurement step, wind speed and wind direction in a measurement area are measured based on changes in the reception timing of the ultrasonic waves received by the reception unit. In the correction step, the measurement results of the measurement unit are corrected using a correction coefficient that varies depending on the wind direction so as to eliminate the influence of obstacles located near the emission unit and the reception unit that may cause resistance to wind toward the measurement area on wind measurement in the measurement area.

[0023] Here, for example, in order to eliminate the influence of obstacles that are disposed near the emitter that emits ultrasonic waves and the receiver that receives ultrasonic waves and that may cause resistance to wind toward the measurement area, the wind speed value measured in the measurement area is corrected using a correction coefficient that varies depending on the wind direction. Here, the emitter and receiver may function as the emitter and receiver using, for example, a single ultrasonic sensor, or dedicated components may be used as the emitter and receiver.

[0024] The ultrasonic waves emitted from the emitter may be received directly by the receiver, or may be received, for example, via a reflecting surface provided at a position facing the emitter and receiver. The emitter and receiver used as a pair may be configured as two sets, one set, or three or more sets. In the measurement step, for example, the timing at which the ultrasonic waves emitted from the emitter are received by the receiver in a windless state is used as a reference, and the wind speed and wind direction are measured by detecting a difference (phase difference) in the reception timing.

[0025] The obstacles include, for example, irregularities, columnar members, etc., located near the transmitter and receiver. This allows the measurement results to be corrected using different correction coefficients depending on the wind direction, even if the influence of obstacles located near the transmitter and receiver changes depending on the wind direction. As a result, it is possible to measure wind speed with high accuracy by eliminating the influence of obstacles located near the transmitter that emits ultrasonic waves and the receiver that receives the emitted ultrasonic waves.

[0026] A fifteenth aspect of the present invention provides a wind measurement program for measuring wind speed and direction, which causes a computer to execute a wind measurement method including an emission step, a reception step, a measurement step, and a correction step. In the emission step, ultrasonic waves are emitted from an emission unit in a predetermined direction. In the reception step, the ultrasonic waves emitted in the emission step are received by a reception unit. In the measurement step, wind speed and wind direction in a measurement area are measured based on changes in the reception timing of the ultrasonic waves received by the reception unit. In the correction step, the measurement results of the measurement unit are corrected using a correction coefficient that varies depending on the wind direction so as to eliminate the influence on wind measurement in the measurement area of ​​obstacles located near the emission unit and the reception unit that may cause resistance to wind toward the measurement area.

[0027] Here, for example, in order to eliminate the influence of obstacles that are disposed near the emitter that emits ultrasonic waves and the receiver that receives ultrasonic waves and that may cause resistance to wind toward the measurement area, the wind speed value measured in the measurement area is corrected using a correction coefficient that varies depending on the wind direction. Here, the emitter and receiver may function as the emitter and receiver using, for example, a single ultrasonic sensor, or dedicated components may be used as the emitter and receiver.

[0028] The ultrasonic waves emitted from the emitter may be received directly by the receiver, or may be received, for example, via a reflecting surface provided at a position facing the emitter and receiver. The emitter and receiver used as a pair may be configured as two sets, one set, or three or more sets. In the measurement step, for example, the timing at which the ultrasonic waves emitted from the emitter are received by the receiver in a windless state is used as a reference, and the wind speed and wind direction are measured by detecting a difference (phase difference) in the reception timing.

[0029] The obstacles include, for example, irregularities, columnar members, etc., that are placed near the emitting unit and receiving unit. This makes it possible to correct the measurement results using different correction coefficients depending on the wind direction, even if the influence of obstacles placed near the emitting unit and receiving unit changes in magnitude depending on the wind direction.

[0030] As a result, the influence of obstacles placed near the emitter that emits ultrasonic waves and the receiver that receives the emitted ultrasonic waves can be eliminated, and the wind speed can be measured with high accuracy.

[0031] (Effects of the Invention) The wind measurement device according to the present invention can measure wind speed with high accuracy by eliminating the influence of obstacles placed near the emitting section that emits ultrasonic waves and the receiving section that receives the emitted ultrasonic waves.

[0032] 1 is an overall perspective view showing the configuration of a weather sensor including a wind measurement device according to an embodiment of the present invention. FIG. 1 is a side view of the weather sensor of FIG. 1. FIG. 2 is a top view of the weather sensor of FIG. 1. FIG. 3 is a cross-sectional view showing the configuration of the upper section of the weather sensor (raindrop detection device) in the cross-sectional view taken along line A-A in FIG. 3. FIG. 4 is a control block diagram of the wind measurement device included in the weather sensor of FIG. 1. FIG. 5 is a cross-sectional view showing the configuration of the middle section of the weather sensor (wind measurement device) in the cross-sectional view taken along line A-A in FIG. 3. FIG. 6 is a schematic diagram showing the influence of wind when the ultrasonic sensor of FIG. 6 emits ultrasonic waves via a reflecting surface to an ultrasonic sensor arranged opposite it. FIG. 7 is a schematic diagram showing the configuration of the ultrasonic sensors included in the wind measurement device of FIG. 6 arranged so as to face each other. FIG. 8 is a diagram explaining the principle of measuring wind speed by detecting a change in the phase difference of the reception timing of ultrasonic waves emitted from the ultrasonic sensor of FIG. 7 relative to a windless state. FIG. 9 is a diagram showing that the wind measurement device of FIG. 6 has multiple stages of correction coefficients prepared for different wind directions depending on the position of an obstacle. FIG. 10 is a perspective view showing three directions of wind blowing into the measurement area of ​​the wind measurement device included in the weather sensor of FIG. 1. 12A, 12B, and 12C are top views showing four ultrasonic sensors installed on the top surface of the wind measurement device of FIG. 11 and the three directions of wind blowing into the measurement area. (a), (b), and (c) are top views showing the results of fluid analysis corresponding to the three wind directions A, B, and C shown in FIG. 12. (a), (b), and (c) are side views showing the results of fluid analysis corresponding to the three wind directions A, B, and C shown in FIG. 12. A diagram showing wind speed that changes due to the influence of obstacles depending on the wind blowing direction in FIG. 12. A flowchart showing the processing flow of a wind measurement method using the wind measurement device of FIG. 11.

[0033] A weather sensor 1 equipped with a wind measurement device 10 according to one embodiment of the present invention will be described below with reference to FIGS. 1 to 16. In this embodiment, unnecessary detailed description may be omitted. For example, detailed description of well-known matters or redundant description of substantially identical configurations may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art. Furthermore, the applicant provides the accompanying drawings and the following description to enable those skilled in the art to fully understand the present invention, and does not intend for them to limit the subject matter recited in the claims.

[0034] (1) Configuration of the weather sensor 1 The weather sensor 1 according to this embodiment is a device that is installed, for example, outdoors and measures rain, wind, illuminance, temperature, humidity, air pressure, etc., and as shown in Figures 1 and 2, it includes a wind measurement device 10, a raindrop detection device 20, an illuminance meter 30, and a thermo-hygro-barometer 40.

[0035] As shown in FIGS. 1 and 2 , the wind measurement device 10 is provided in the middle section of the weather sensor 1 and measures the speed and direction of wind passing through the gap (measurement area A1 (see FIG. 6 )) between the raindrop detection device 20 and the thermo-hygro-barometer 40. The detailed configuration of the wind measurement device 10 will be described later. As shown in FIGS. 1 and 2 , the raindrop detection device 20 is provided in the upper section of the weather sensor 1 and detects raindrops that pass through a predetermined opening 21 a (see FIG. 3 , etc.) on the top surface of the housing 21, and calculates the amount of rainfall by detecting the size of the detected raindrops and the amount per unit time.

[0036] More specifically, the raindrop detection device 20 has a light source 22a and a light receiving unit 22b (see FIG. 4) inside the housing 21. The light source 22a and the light receiving unit 22b are arranged facing each other on the inner wall surface 21b of the opening 21a, as shown in FIG. 4. The light source 22a is, for example, a light emitting diode (LED), and emits infrared light toward the light receiving unit 22b via a collimating lens and a condensing lens (neither of which are shown).

[0037] The light receiving unit 22b is, for example, a photodiode, and is positioned opposite the light source unit 22a. The light receiving unit 22b receives light condensed through a condensing lens (not shown). The light source unit 22a irradiates a raindrop detection area formed between the light source unit 22a and the light receiving unit 22b with light. The presence or absence of raindrops is detected when raindrops block part of the light detected by the light receiving unit 22b, reducing the amount of light received by the light receiving unit 22b.

[0038] The raindrop detection device 20 has a plurality of legs 23 erected on the upper surface of the base 24, and is connected to the wind measurement device 10 constituting the middle section of the weather sensor 1 via the legs 23 and the base. As shown in Figures 1 and 2, the illuminance meter 30 is provided in the upper section of the weather sensor 1 together with the raindrop detection device 20, and measures illuminance as one piece of weather information. As shown in Figures 1 and 2, the thermo-hygro-barometer 40 is provided in the lower section of the weather sensor 1, and measures temperature (air temperature), humidity, and air pressure as weather information.

[0039] (2) Configuration of the wind measurement device 10 The wind measurement device 10 of this embodiment is a device that measures, for example, outdoor wind speed and wind direction, and as shown in Figure 5, is equipped with ultrasonic sensors (emitter, receiver) 11a, 11b, 11c, and 11d, a pillar member (obstacle) 14 and a base (obstacle) 15 (see Figure 6, etc.), ultrasonic driver units 16a, 16b, 16c, and 16d, a logic IC 17a, a multiplexer 17b, an ultrasonic sensor IC 17c, a wind microcomputer (measurement unit, correction unit) 18, a memory (storage unit) 18a, and a relay microcomputer 19.

[0040] As shown in FIG. 1 and other figures, ultrasonic sensors (emitters, receivers) 11a, 11b, 11c, and 11d are arranged on the upper surface (first surface) 12a of the base 12. The ultrasonic sensors 11a, 11b, 11c, and 11d are used in pairs (ultrasonic sensors 11a and 11b and ultrasonic sensors 11c and 11d) arranged facing each other. One of the pair of ultrasonic sensors 11a and 11b functions as an emitter that emits ultrasonic waves, and the other functions as a receiver that receives ultrasonic waves. These functions can also be switched in reverse.

[0041] For example, when ultrasonic sensor 11a emits an ultrasonic wave, ultrasonic sensor 11b, which is positioned opposite to ultrasonic sensor 11a, receives the ultrasonic wave emitted from ultrasonic sensor 11a and reflected by reflecting surface 13 shown in Fig. 6. When ultrasonic sensor 11b emits an ultrasonic wave, ultrasonic sensor 11a, which is positioned opposite to ultrasonic sensor 11b, receives the ultrasonic wave emitted from ultrasonic sensor 11b and reflected by reflecting surface 13 shown in Fig. 6.

[0042] Similarly, when ultrasonic sensor 11c emits an ultrasonic wave, ultrasonic sensor 11d, which is positioned opposite ultrasonic sensor 11c, receives the ultrasonic wave emitted from ultrasonic sensor 11c and reflected by reflecting surface 13 shown in Fig. 6. When ultrasonic sensor 11d emits an ultrasonic wave, ultrasonic sensor 11c, which is positioned opposite ultrasonic sensor 11c, receives the ultrasonic wave emitted from ultrasonic sensor 11d and reflected by reflecting surface 13 shown in Fig. 6.

[0043] 6, the pillar members (obstacles) 14 are erected on the upper surface 12a on which the ultrasonic sensors 11a, 11b, 11c, and 11d are arranged, are provided around the measurement area A1, and support the base 24 from below. Since the pillar members 14 are provided near the ultrasonic sensors 11a, 11b, 11c, and 11d, they may act as resistance to wind flowing toward the measurement area A1 depending on the wind direction.

[0044] As shown in FIG. 6 , the base (obstacle) 15 is provided on the top surface 12a on which the ultrasonic sensors 11a, 11b, 11c, and 11d are arranged, and protrudes from the top surface 12a while supporting the ultrasonic sensors 11a, 11b, 11c, and 11d. Therefore, depending on the wind direction, the portion of the base 15 protruding from the top surface 12a may create resistance to the wind toward the measurement area A1. The ultrasonic drivers 16a, 16b, 16c, and 16d each have an ultrasonic sensor driver IC (Integrated Circuit) that converts a logic signal (0-3.3V differential pulse signal) during transmission into an ultrasonic drive signal (0-18V), and the wind microcomputer 18 controls the drive of each of the four ultrasonic sensors 11a, 11b, 11c, and 11d while switching between them.

[0045] The logic IC 17a, for example, has an enable function, generates switching and differential inputs, and inputs them to the ultrasonic sensor driving IC. The multiplexer 17b is connected to the ultrasonic sensors 11a, 11b, 11c, and 11d, and acquires the values ​​of ultrasonic waves measured by switching the ultrasonic sensors 11a, 11b, 11c, and 11d that function as receivers, and transmits the values ​​as analog signals to the ultrasonic sensor IC 17c.

[0046] The ultrasonic sensor IC 17c controls the ultrasonic sensors 11a, 11b, 11c, and 11d that function as receivers, while switching between the ultrasonic sensors 11a, 11b, 11c, and 11d using the wind microcomputer 18. The ultrasonic sensor IC 17c also receives and amplifies ultrasonic waves while switching between the ultrasonic sensors 11a, 11b, 11c, and 11d in the multiplexer 17b.

[0047] The wind microcomputer (measurement unit, correction unit) 18 measures the wind speed and direction in the measurement area A1 based on changes in the reception timing of ultrasonic waves received by the ultrasonic sensors 11 a, 11 b, 11 c, and 11 d that function as receivers. The wind microcomputer 18 then corrects the measurement results using a correction coefficient that varies depending on the wind direction so as to eliminate the influence of obstacles such as the base 15 on the wind measurement in the measurement area A1.

[0048] The correction coefficients used by the wind microcomputer 18 are stored in memory 18a, and when performing correction processing, the correction coefficient corresponding to the wind direction is retrieved from memory 18a and used. The memory (storage unit) 18a acquires and stores different correction coefficients depending on the wind direction from the results of fluid analysis simulations. The relay microcomputer 19, for example, communicates with the wind microcomputer 18, acquires data from the temperature / humidity and air pressure sensors on other boards, and relays data from the rain sensor board. Communication between each microcomputer (wind microcomputer 18, relay microcomputer 19) is performed using, for example, a universal asynchronous receiver / transmitter (UART).

[0049] <Wind measurement principle> The wind measurement device 10 of this embodiment is equipped with four ultrasonic sensors 11a, 11b, 11c, and 11d, which are switched to function as emitters and receivers to measure the speed and direction of wind in the measurement area A1.

[0050] Specifically, the wind measurement device 10 utilizes the fact that the time it takes for an emitted ultrasonic wave to be received between a pair of ultrasonic sensors 11a and 11b or ultrasonic sensors 11c and 11d arranged opposite each other changes between when there is no wind and when there is wind, as shown in Figure 7, and calculates the wind speed by finding the change as the phase difference when the ultrasonic wave is received.

[0051] For example, as shown in Fig. 7, when the wind is blowing from left to right in the figure, the ultrasonic waves emitted from the ultrasonic sensors 11a and 11c are received earlier by the opposing ultrasonic sensors 11b and 11d than when there is no wind. On the other hand, when the wind is blowing from right to left in the figure, contrary to Fig. 7, the ultrasonic waves emitted from the ultrasonic sensors 11a and 11c are received later by the opposing ultrasonic sensors 11b and 11d than when there is no wind.

[0052] The wind speed Vab between the ultrasonic sensors 11a and 11b shown in FIG. 8 is calculated by the following formula. The same applies to the wind speed Vcd between the ultrasonic sensors 11c and 11d. Vab=Δt×(c ２ ) / (2 × L) (m / s) where Δt = (Tab: phase difference change on the return journey) - (Tba: phase difference change on the outgoing journey) (sec) c = speed of sound (m / s) = 331.5 + (0.61 × temperature (°C)) L = distance between sensors (m) Here, as shown in FIG. 9, if the time period during which the phase difference changes on the outgoing journey from the ultrasonic sensors 11a, 11c on the emitting side to the ultrasonic sensors 11b, 11d on the receiving side is Tab (sec), and the time period during which the phase difference changes on the opposite journey from the ultrasonic sensors 11b, 11d on the emitting side to the ultrasonic sensors 11a, 11c on the receiving side is Tba (sec), then the time period during which the phase difference changes compared to when there is no wind is represented as Δt.

[0053] Therefore, the wind measurement device 10 can measure the wind speed by calculating the time Δt of change in the phase difference compared to a windless state. Furthermore, in order to calculate the direction of the wind passing through the measurement area A1, the wind measurement device 10 adds up the measurement results Vab and Vcd of the paired ultrasonic sensors 11 a, 11 b and the paired ultrasonic sensors 11 c, 11 d to calculate the final wind speed value and wind direction.

[0054] <Measurement Value Correction Process> As described above, in the wind measurement device 10 of this embodiment, obstacles such as unevenness and protrusions (the pillar members 14 and the base 15) are present near the measurement area A1 between the opposing ultrasonic sensors 11 a, 11 b and the opposing ultrasonic sensors 11 c, 11 d. Therefore, depending on the wind direction, there is a risk of errors in wind measurement due to the influence of the base 15, etc.

[0055] In the wind measurement device 10 of this embodiment, in order to eliminate the directional dependency of errors in measurement values ​​caused by such obstacles, the measurement values ​​are corrected using correction coefficients that differ depending on the wind direction. Specifically, the wind measurement device 10 stores wind direction-dependent correction coefficients shown in Fig. 10 in the memory 18a shown in Fig. 5. Note that Fig. 10 shows that the wind direction-dependent correction coefficients also change because the way the wind is received differs depending on the structure of the wind measurement device 10 (the presence or absence of obstacles, the number of obstacles, etc.).

[0056] The wind direction dependent correction coefficient is prepared in two stages, for example, with different values ​​depending on the wind angle (for example, (45 degrees, 135 degrees, 225 degrees, 315 degrees) and (0 degrees, 90 degrees, 180 degrees, 270 degrees)), and is selected according to the measured wind speed value and wind direction. The following patterns are possible examples of wind direction dependent correction coefficients prepared in two stages.

[0057] Pattern (i) 1st stage (0 degrees, 90 degrees, 180 degrees, 270 degrees) -> 1.1 2nd stage (45 degrees, 135 degrees, 225 degrees, 315 degrees) -> 1.0 Pattern (ii) 1st stage (0 degrees, 90 degrees, 180 degrees, 270 degrees) -> 1.22 2nd stage (45 degrees, 135 degrees, 225 degrees, 315 degrees) -> 1.08 Note that pattern (i) is an example where there are few obstacles overall, and the impact of obstacles on the wind is small, so the correction coefficient is 1.1 to 1.0.

[0058] Pattern (ii) is an example where there are many obstacles overall, and the influence of the obstacles on the wind is large, so the correction coefficient is larger than in pattern (i), at 1.22 to 1.08. As a result, the wind speed and the wind velocity are calculated using the wind direction-dependent correction coefficient shown in Figure 10, which is prepared in multiple stages depending on the wind direction, according to the following relational expression.

[0059] That is, the final wind speed and wind direction are calculated by adding up the following Vab and Vcd. Wind direction (degrees) = arctan (Vab / Vcd) Wind direction dependent magnification (The wind direction magnification to be used is determined from the wind direction in 45° increments, and the wind direction dependent magnification is calculated) n = wind direction / 45 (the result is rounded down) Wind direction dependent magnification = wind direction magnification (n) + mod (wind direction, 45) / 45 × (wind direction magnification (n+1) - wind direction magnification (n)) Wind speed (m / s) = wind direction dependent magnification × √((Vab) ２ +(Vcd) ２ For example, when the wind direction is 0°, the wind direction dependent magnification is calculated using the wind direction magnification (0) and wind direction magnification (1) in the wind speed magnification conversion table below.

[0060] For example, when the wind direction is 45°, the wind direction dependent magnification is calculated using the wind direction magnification (1) and wind direction magnification (2) in the following wind speed magnification conversion table. The wind speed magnification conversion table is set as follows: Wind speed multiplier (0) = 1.15, wind speed multiplier (1) = 1 Wind speed multiplier (2) = 1.15, wind speed multiplier (3) = 1 Wind speed multiplier (4) = 1.15, wind speed multiplier (5) = 1 Wind speed multiplier (6) = 1.15, wind speed multiplier (7) = 1 Specifically, When the wind direction is 0° or more and less than 45°, n = 0 → wind speed multiplier (0) = 1.15, wind speed multiplier (1) = 1 is used, and for angles in between, the multiplier is adjusted between 1.15 and 1 by substituting the angle for the wind direction in the wind direction dependent multiplier formula above. When the wind direction is 45° or more and less than 90°, n = 1 → wind speed multiplier (1) = 1, wind speed multiplier (2) = 1.15 is used, and for angles in between, the multiplier is adjusted between 1 and 1.15 by substituting the angle for the wind direction in the wind direction dependent multiplier formula above.・When the wind direction is 90° or more and less than 135°, n = 2 → Use wind speed multiplier (2) = 1.15, wind speed multiplier (3) = 1. For angles in between, use the wind speed multiplier (2) = 1.15 and wind speed multiplier (3) = 1. For angles in between, use the wind speed multiplier (3) = 1.15 and wind speed multiplier (4) = 1.15 ...4) = 1.15 and wind speed multiplier (5) = 1. For angles in between, use the wind speed multiplier (4) = 1.15 and wind speed multiplier (5) = 1. For angles in between, use the wind speed multiplier (4) = 1.15 and wind speed multiplier (5) = 1.・When the wind direction is 225° or more and less than 270°, n = 5 → wind speed multiplier (5) = 1, wind speed multiplier (6) = 1.15 are used, and for angles in between, a multiplier adjustment between 1 and 1.15 is made by substituting the angle for wind direction in the wind direction dependent multiplier formula above. ・When the wind direction is 270° or more and less than 315°, n = 6 → wind speed multiplier (6) = 1.15, wind speed multiplier (7) = 1 are used, and for angles in between, a multiplier adjustment between 1.15 and 1 is made by substituting the angle for wind direction in the wind direction dependent multiplier formula above. ・When the wind direction is 315° or more and less than 360°, n = 7 → wind speed multiplier (7) = 1, wind speed multiplier (0) = 1.15 are used, and for angles in between, a multiplier adjustment between 1 and 1.15 is made by substituting the angle for wind direction in the wind direction dependent multiplier formula above.

[0061] For example, consider the case where winds blow into measurement area A1 from three directions, A, B, and C, as shown in Fig. 11. In this case, as shown in Fig. 12, the wind from direction A may be significantly affected because it hits the protruding portion of base 15 of ultrasonic sensor 11b. Furthermore, although the wind from direction B is less affected than the wind from direction A, it may still be affected to some extent by base 15.

[0062] 13(a) to 13(c) are top views showing the results of a fluid simulation that illustrates the influence on the measurement area A1 when wind blows from directions A, B, and C shown in FIGS. 11 and 12 with the wind measurement device 10 of this embodiment installed at the center position.

[0063] 14(a) to 14(c) are side views showing the results of a fluid simulation illustrating the influence on the measurement area A1 when the wind measurement device 10 of this embodiment is installed at a central position and wind blows from directions A, B, and C shown in Figures 11 and 12. As shown in Figures 13(a) and 14(a), the wind speed of the wind from direction A changes (decreases) in the measurement area A1 due to the influence of the base 15, and it is considered necessary to correct the measurement value.

[0064] As shown in Figures 13(b) and 14(b), the wind from direction B is less affected than from direction A, but the wind speed changes (decreases) slightly in measurement area A1 due to the influence of base 15, and it is considered necessary to correct the measurement value. As shown in Figures 13(c) and 14(c), the wind from direction C is hardly affected by base 15 and pillar member 14 in measurement area A1 compared to directions A and B, and it is considered almost unnecessary to correct the measurement value.

[0065] It is assumed that although the wind from direction C hits the pillar member 14, it is hardly affected due to the small thickness of the pillar member. Therefore, although the results of this simulation showed that there was almost no effect from the pillar member 14, it is assumed that there is a possibility of an effect depending on the thickness of the pillar member 14. As described above, the results of performing a fluid simulation on winds from directions A, B, and C show that the error in the measurement value in measurement area A1 is directional dependent.

[0066] For this reason, the wind measurement device 10 of this embodiment corrects the measurement value (wind speed) using an appropriate correction coefficient depending on the measured wind direction. That is, when wind is detected from direction A, the wind is most affected by the obstacle (base 15), and therefore, as shown in Figure 15, the wind will be weaker than the circle (◯) indicating a windless state. For this reason, in direction A, a correction coefficient with a large difference is used to correct the wind (▲) that has been weakened due to the influence of the obstacle, as shown in Figure 10.

[0067] When wind is detected from direction B, it is affected by an obstacle (base 15), and as a result, the wind is slightly weaker than the circle (◯) indicating a windless state, as shown in Fig. 15. For this reason, in direction B, a correction coefficient is used that is smaller in difference than in direction A but larger in difference than in direction C, in order to correct the wind (▲) that has been slightly weakened due to the influence of the obstacle, as shown in Fig. 10.

[0068] When wind from direction C is detected, it is hardly affected by the obstacle (base 15), and therefore the wind is not weaker than the circle (◯) indicating a windless state, as shown in Fig. 15. Therefore, in the direction C, a correction coefficient with little difference is used to correct the wind (▲) that is hardly affected by the obstacle, as shown in Fig. 10.

[0069] <Wind Measurement Method> With the configuration described above, the wind measurement device 10 of this embodiment measures wind speed and direction according to the flowchart shown in Fig. 16, and corrects the measurement values ​​using correction coefficients that vary depending on the wind direction to eliminate the influence of obstacles (such as the base 15). That is, in step S11, for example, ultrasonic sensors 11a and 11c emit ultrasonic waves.

[0070] Next, in step S12, the ultrasonic waves emitted from the ultrasonic sensors 11a and 11c are received by the opposing ultrasonic sensors 11b and 11d via the reflecting surface 13. Next, in step S13, the wind microcomputer 18 calculates the wind speed and direction in each direction (between a and b, between c and d) based on the phase difference between the phase of the received ultrasonic waves and the phase indicating the reception timing in a windless state.

[0071] Next, in step S14, the wind microcomputer 18 obtains from the memory 18a a correction coefficient corresponding to the wind direction calculated in step S13. Next, in step S15, the wind microcomputer 18 corrects the wind speed in each direction (between a and b, between c and d) using the correction coefficient obtained in step S14. Next, in step S16, the wind microcomputer 18 calculates the final wind speed and direction from the wind speed and direction in each direction (between a and b, between c and d).

[0072] <Major Features> As shown in FIG. 3 , the wind measurement device 10 of this embodiment includes ultrasonic sensors 11a, 11b, 11c, and 11d, a measurement area A1, a wind microcomputer 18, and a base 15. The ultrasonic sensors 11a and 11c emit ultrasonic waves in a predetermined direction. The ultrasonic sensors 11b and 11d receive the ultrasonic waves emitted from the ultrasonic sensors 11a and 11c. The measurement area A1 is located between the ultrasonic sensors 11a, 11b, 11c, and 11d. The wind microcomputer 18 measures the wind speed in the measurement area A1 based on changes in the timing at which the ultrasonic waves are received. The base 15 is located near the ultrasonic sensors 11a, 11b, 11c, and 11d and can act as a resistance to wind heading toward the measurement area A1. The wind microcomputer 18 corrects the measurement results using different correction coefficients depending on the wind direction to eliminate the influence of the base 15 on wind measurement in the measurement area A1.

[0073] This allows the measurement results to be corrected using different correction coefficients depending on the wind direction, even if the influence of obstacles such as the bases 15 arranged near the ultrasonic sensors 11 a, 11 b, 11 c, and 11 d changes depending on the wind direction. As a result, it is possible to measure wind speed with high accuracy by eliminating the influence of obstacles such as the bases 15 arranged near the ultrasonic sensors 11 a, 11 b, 11 c, and 11 d that emit and receive ultrasonic waves.

[0074] [Other Embodiments] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the invention.

[0075] (A) In the above embodiment, the present invention has been described as an example of a wind measurement device and a wind measurement method. However, the present invention is not limited to this. For example, the present invention may be realized as a wind measurement program that causes a computer to execute the above-described wind measurement method. This wind measurement program is stored in a memory (storage unit) installed in the wind measurement device, and a CPU loads the wind measurement program stored in the memory and causes the hardware to execute each step. More specifically, the same effect as described above can be achieved by the CPU loading the wind measurement program and executing the above-described emission step, reception step, measurement step, and correction step. The present invention may also be realized as a recording medium storing the wind measurement program.

[0076] (B) In the above embodiment, an example was described in which the wind measurement device 10 includes two pairs of ultrasonic sensors 11a, 11b, 11c, and 11d, for a total of four sensors. However, the present invention is not limited to this.

[0077] For example, the wind measurement device may be configured with three ultrasonic sensors. In this case, each ultrasonic sensor is arranged at approximately equal angular intervals and functions as an emitter and a receiver, making it possible to measure the wind speed and direction in the measurement area between the three points. Alternatively, the wind measurement device may be configured with two ultrasonic sensors or five or more ultrasonic sensors.

[0078] (C) In the above embodiment, an example was described in which the ultrasonic sensors 11a, 11b and the ultrasonic sensors 11c, 11d arranged opposite each other are switchable between functioning as emitters and functions as receivers. However, the present invention is not limited to this. For example, an ultrasonic sensor dedicated to emitting and an ultrasonic sensor dedicated to receiving may be arranged opposite each other.

[0079] (D) In ​​the above embodiment, the base 15 was described as an example of an obstacle that affects wind measurement in the measurement area. However, the present invention is not limited to this. For example, in the above embodiment, if the thickness or placement of a pillar member, which had almost no effect on wind measurement, is different, the pillar member may be set as an obstacle and the measurement value may be corrected. Alternatively, objects other than the base or pillar member that affect the wind flowing into the measurement area may be recognized as obstacles and the measurement value may be corrected.

[0080] (E) In the above embodiment, an example was described in which ultrasonic waves are received between two opposing ultrasonic sensors 11a and 11b or two opposing ultrasonic sensors 11c and 11d via the reflecting surface 13. However, the present invention is not limited to this. For example, ultrasonic waves may be received directly between the opposing ultrasonic sensors without passing through a reflecting surface.

[0081] (F) In the above embodiment, an example was described in which the correction coefficient is prepared in the memory 18a in two stages depending on the wind speed. However, the present invention is not limited to this. For example, the correction coefficient may be prepared in one stage, or in three or more stages depending on the wind speed, etc.

[0082] (G) In the above embodiment, the wind measurement device 10 is described as being incorporated into the weather sensor 1. However, the present invention is not limited to this. For example, the wind measurement device may be configured to be used independently.

[0083] <Note> The wind measurement device of the first invention is a wind measurement device that measures wind speed and wind direction, and comprises: an emission unit that emits ultrasonic waves in a predetermined direction; a receiving unit that receives the ultrasonic waves emitted from the emission unit; a measurement area provided between the emission unit and the receiving unit; a measurement unit that measures wind speed and wind direction in the measurement area based on changes in the reception timing of the ultrasonic waves received by the receiving unit; obstacles that are provided near the emission unit and the receiving unit and that may cause resistance to wind heading towards the measurement area; and a correction unit that corrects the measurement results of the measurement unit using correction coefficients that differ depending on the wind direction so as to eliminate the influence of the obstacles on wind measurement in the measurement area.

[0084] A second aspect of the present invention is the wind measurement device of the first aspect, wherein the correction unit obtains the correction coefficient from a simulation result showing a wind flow in the measurement area when the direction of the wind toward the measurement area is changed. A third aspect of the present invention is the wind measurement device of the second aspect, further comprising a memory unit that stores the correction coefficient obtained from the simulation result.

[0085] A fourth aspect of the invention is the wind measurement device of the third aspect, wherein the memory unit stores the correction coefficient at multiple levels. A fifth aspect of the invention is the wind measurement device of the fourth aspect, wherein the correction coefficient is set at multiple levels with different values ​​for each predetermined wind direction. A sixth aspect of the invention is the wind measurement device of the fourth or fifth aspect, wherein the correction coefficient is set at multiple levels depending on the position of the obstacle.

[0086] A seventh aspect of the present invention is the wind measurement device according to any one of the first to sixth aspects of the present invention, further comprising a reflecting surface that reflects the ultrasonic waves emitted from the emitting unit toward the receiving unit. A eighth aspect of the present invention is the wind measurement device according to the seventh aspect of the present invention, wherein the emitting unit and the receiving unit are arranged symmetrically about the central axis of the reflecting surface.

[0087] A wind measurement device according to a ninth aspect of the present invention is the wind measurement device according to any one of the first to eighth aspects of the present invention, wherein the emitter and the receiver are provided as two pairs.A wind measurement device according to a tenth aspect of the present invention is the wind measurement device according to any one of the first to ninth aspects of the present invention, wherein the emitter and the receiver are ultrasonic sensors provided as a pair and are used in a switchable state with respect to each other.

[0088] An eleventh aspect of the present invention is the wind measurement device of any one of the first to tenth aspects, wherein the obstacle is a base provided on a first surface on which the emitter and the receiver are arranged and protruding from the first surface while supporting the emitter and the receiver. A twelfth aspect of the present invention is the wind measurement device of the eleventh aspect, further comprising a reflecting surface that reflects ultrasonic waves emitted from the emitter toward the receiver, and the base supports the emitter and the receiver at an angle with respect to the first surface so that the ultrasonic waves are emitted from the emitter obliquely with respect to the first surface and received by the receiver via the reflecting surface obliquely with respect to the first surface.

[0089] A thirteenth aspect of the present invention is the wind measurement device of any one of the first to twelfth aspects of the present invention, wherein the obstacle is a column member erected on a first surface on which the emission unit and the reception unit are disposed and provided around the measurement area. A fourteenth aspect of the present invention is a wind measurement method for measuring wind speed and wind direction, comprising: an emission step of emitting ultrasonic waves in a predetermined direction from an emission unit; a reception step of receiving the ultrasonic waves emitted in the emission step with a reception unit; a measurement step of measuring the wind speed and wind direction in the measurement area with a measurement unit based on changes in reception timing of the ultrasonic waves received by the reception unit; and a correction step of correcting the measurement result of the measurement unit using a correction coefficient that varies depending on the wind direction so as to eliminate the influence of obstacles provided near the emission unit and the reception unit that may cause resistance to wind toward the measurement area on wind measurement in the measurement area.

[0090] A wind measurement program according to a fifteenth aspect of the present invention is a wind measurement program for measuring wind speed and wind direction, and causes a computer to execute a wind measurement method comprising: an emission step of emitting ultrasonic waves in a predetermined direction from an emission unit; a reception step of receiving the ultrasonic waves emitted in the emission step in a receiving unit; a measurement step of measuring the wind speed and wind direction in a measurement area in a measurement unit based on changes in the reception timing of the ultrasonic waves received by the receiving unit; and a correction step of correcting the measurement results in the measurement unit using a correction coefficient that varies depending on the wind direction, so as to eliminate the influence on wind measurement in the measurement area of ​​obstacles that are located near the emission unit and the receiving unit and that may cause resistance to wind toward the measurement area.

[0091] The wind measurement device of the present invention has the effect of being able to measure wind speed with high accuracy by eliminating the influence of obstacles placed near the emitting section that emits ultrasonic waves and the receiving section that receives the emitted ultrasonic waves, and therefore can be widely applied to devices installed in weather sensors, etc.

[0092] DESCRIPTION OF SYMBOLS 1 Weather sensor 10 Wind measurement device 11a, 11b, 11c, 11d Ultrasonic sensor (emitting unit, receiving unit) 12 Base 12a Top surface (first surface) 13 Reflecting surface 14 Pillar member (obstacle) 15 Base portion (obstacle) 16a, 16b, 16c, 16d Ultrasonic driving unit 17a Logic IC 17b Multiplexer 17c Ultrasonic sensor IC 18 Wind microcomputer (measuring unit, correcting unit) 18a Memory (storage unit) 19 Relay microcomputer 20 Raindrop detection device 21 Housing portion 21a Opening 21b Inner wall surface 22a Light source portion 22b Light receiving unit 30 Illuminance meter 40 Thermo-hygro-barometer A1 Measurement area

Claims

1. A wind measurement device that measures wind speed and direction, comprising: an emission unit that emits ultrasonic waves in a predetermined direction; a receiving unit that receives the ultrasonic waves emitted from the emission unit; a measurement area provided between the emission unit and the receiving unit; a measurement unit that measures wind speed and direction in the measurement area based on changes in the reception timing of the ultrasonic waves received by the receiving unit; an obstacle provided near the emission unit and the receiving unit that may cause resistance to wind heading toward the measurement area; and a correction unit that corrects the measurement results of the measurement unit using a correction coefficient that differs depending on the wind direction so as to eliminate the influence of the obstacle on the wind measurement in the measurement area.

2. The wind measurement device according to claim 1, wherein the correction unit obtains the correction coefficient from the results of a simulation showing the wind flow in the measurement area when the direction of the wind heading toward the measurement area is changed.

3. The wind measurement device according to claim 2, further comprising a memory unit for storing the correction coefficient obtained from the result of the simulation.

4. The wind measurement device according to claim 3, wherein the memory unit stores the correction coefficients in a plurality of stages.

5. The wind measurement device according to claim 4, wherein the correction coefficient is set at a plurality of different values ​​for each predetermined wind direction.

6. The wind measurement device according to claim 4 or 5, wherein the correction coefficient is set in a plurality of stages according to the position of the obstacle.

7. The wind measurement device according to claim 1 or 2, further comprising a reflecting surface that reflects the ultrasonic waves emitted from the emitting portion in the direction of the receiving portion.

8. The wind measurement device according to claim 7, wherein the emission section and the reception section are arranged in line symmetry with respect to the central axis of the reflection surface.

9. The wind measurement device according to claim 1 or 2, wherein the emission section and the reception section are provided in two pairs.

10. The wind measurement device according to claim 1 or 2, wherein the emission unit and the reception unit are ultrasonic sensors provided as a pair and are used in a switchable state with respect to each other.

11. A wind measurement device as described in claim 1 or 2, wherein the obstacle is provided on a first surface on which the emitting unit and the receiving unit are arranged, and is a base portion protruding from the first surface while supporting the emitting unit and the receiving unit.

12. A wind measurement device as described in claim 11, further comprising a reflecting surface that reflects the ultrasonic waves emitted from the emitting portion in the direction of the receiving portion, and the base portion supports the emitting portion and the receiving portion at an angle to the first surface so that the ultrasonic waves are emitted from the emitting portion at an angle to the first surface and received at the receiving portion via the reflecting surface at an angle to the first surface.

13. The wind measurement device according to claim 1 or 2, wherein the obstacle is a pillar member erected on a first surface on which the emission unit and the reception unit are arranged and provided around the measurement area.

14. A wind measurement method for measuring wind speed and direction, comprising: an emission step of emitting ultrasonic waves in a predetermined direction from an emission unit; a receiving step of receiving the ultrasonic waves emitted in the emission step in a receiving unit; a measurement step of measuring the wind speed and wind direction in a measurement area in the measurement unit based on changes in the reception timing of the ultrasonic waves received by the receiving unit; and a correction step of correcting the measurement results in the measurement unit using a correction coefficient that changes according to the wind direction, so as to eliminate the influence on the wind measurement in the measurement area of ​​obstacles that are located in the vicinity of the emission unit and the receiving unit and that may cause resistance to the wind toward the measurement area.

15. A wind measurement program that causes a computer to execute a wind measurement method for measuring wind speed and direction, comprising: an emission step of emitting ultrasonic waves in a predetermined direction from an emission unit; a receiving step of receiving the ultrasonic waves emitted in the emission step in a receiving unit; a measurement step of measuring the wind speed and wind direction in a measurement area in the measurement unit based on changes in the reception timing of the ultrasonic waves received by the receiving unit; and a correction step of correcting the measurement results in the measurement unit using a correction coefficient that changes according to the wind direction, so as to eliminate the influence on the wind measurement in the measurement area of ​​obstacles that are located in the vicinity of the emission unit and the receiving unit and that may become a resistance to the wind toward the measurement area.

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