Research on observation accuracy of vertical doppler rider in complex terrain (examination of differences and correction methods by average)


This article is2021Year11Held in the month43A part of the "research on the observation accuracy of the vertical doppler rider in complex terrain (study of average and correction methods)" announced at the symposium of the wind power energy is re -edited.

1.First of all

In the wind situation survey, the three -cup wind meter of the wind status observation tower (hereinafter referred to as "" "" "CUP"") And the arrow -type wind direction (hereinafter, "" ""VaneIn addition to the conventional style observation method by), in recent years, a vertical doppler rider (hereinafter referred to as "" "" "" ""VL") The method has become common.2021Year7"Wind Farm Certificate Remodeling Wind Power Edition" of the Japan Maritime Association released on the month1)(Less than,"NK"Guidelines")2/3If the observation cannot be performed at the above position,VLRemote sensing devices such as (hereinafter, "" "" "RSDIt is clearly stated that the combination of combination with) is possible.

In complex terrain such as mountainous areasVLRegarding observations, it is clear that the accuracy of wind speed measurement will decrease if the unevenness of the surrounding terrain is large.2)3)4)。 TheseVLAs an attempt to reduce measurement errorsFCRFlow Complexity Recognition) A device equipped with a correction called) has appeared, but for the correction effect.CUPorVaneIt is necessary to perform sufficient verification using the actual measurement data of. again,VLIt is recorded as an observation value depending on the model of10There are differences in the average wind speed and wind direction, and the results may vary slightly depending on the models and data used.5)It is also a point to be careful.

Therefore, in this paper, in complex terrainVLAbout observationFCRFor the purpose of quantifying the differences due to the averaging method and the wind status measurement systemCUPVaneVerification was conducted by referring to the measurement data.

2. Target areas and breeze observations

The observation point is located on the ridge in the Kyushu Mountains (Figure)1See), with the wind status observation towerVLWe analyzed using data.

 

 

Figure 1 The positional relationship between the wind status observation tower and the VL

table1In addition, the outline of the wind status observation tower is shown. In this article,59.6mTall2HornCUPWhen57.0mTallVaneGained in10We analyzed the average wind speed and wind value as a true value.

 Table 1 Overview of the wind status observation tower

table2,VLIs an overview of. For verification,VaisalaMade by companyWindCube v2.1Using the wind status observation towerCUPWhenVaneIn conjunction with the high altitude57mWith high wind speed60mHigh wind direction scalar average, vector average, vector average-Fcrof3Kind10Average valueVLUsed as an observation value.

Table 2 VL Overview 

up to dateWindCubeThe scalar average, vector average, hybrid average3The kind of horizontal wind speed data is stored7)。 The scalar average is calculated by simply averaging the east and west components of the horizontal wind speed and the north -south ingredients in the average time, and the vector average is calculated by average east and west and north -south ingredients. In addition, the hybrid average is a synthesis of the scalar average and the vector average, but this paper is not eligible for analysis.

WindCubeInstalled inFCRIn the function, from the latitude and longitude information at the observation point,100mThe wind speed in complex terrain is corrected based on the topographic analysis results down from the resolution terrain dataset. For more informationVaisalaCompany report8)Please refer to

3. Results and consideration

3.1 Evaluation standards for observation data

CUPVaneIs the true valueVLThe accuracy evaluation index in correlation analysis is more severe among the NK guidelines1)The standard for (table)3reference)

 Table 3 correlation between the air -operating tower specified in the NK guidelines and the observation data by RSD1) 

3.2 Comparison between VL and wind status observation tower

On the horizontal axisCUPVaneObservation value, vertical axisVLFigure 2 shows the wind direction and wind speed spray diagram as the observed value.NKBased on the guidelinesVLTable of accuracy verification results of observation values4Each is shown. From Fig. 2, the wind directionR2All0.972[-]The result was no big difference.VLThere is a slight error in the wind direction, but the average method is also a table.4ofNKThe standard of the guidelines was met and the result was highly measured. Wind speedbiasIs the scalar average-4.86[%], The vector average-7.65[%], Vector average-FcrBut-0.85[%]have become. In this way, the scalar average and the vector average areCUPYou can see that the wind speed is measured lower than. For wind speed, in all methodsR2>0.98Although it satisfies, the vector average for the tilt of the regression straight line-FcrOnly0.981.02I met the standards. On the other hand, the wind direction was satisfied with all average methods.

From the above, on this site, the vector average-FcrIt was found that the average method was corrected to the high wind speed side for the vector average wind speed, and showed a better correlation than other average methods.

 

FIG. 2 on the horizontal axis, VL observation value ((A) scalar average, vector average -FCR) on the horizontal axis ((b) vector average -FCR) (upper tier) wind direction and (lower) wind speed. Spraying diagram * The ash line in the figure is a regression straight line, indicating the statistical amount in the upper left.

Table 4 Wind speed and wind direction accuracy verification result

3.3 VL verification by direction of wind speed

In the case of a complex terrain, the precision of the observed wind speed may decrease due to the terrain located on the upper side of the wind. Therefore,VLTo evaluate the accuracy of wind speed observation values ​​by wind, on the horizontal axisVaneWind direction, vertical axisCUPTo wind speedVL(Scalar average, vector average, vector average-Fcr) Figure 3 shows a spray diagram with a ratio of wind speed. Regarding the scalar average and the vector average, the average bin average in each wind direction1It shows a lower value. On the other hand, the vector average-FcrThe average value of the wind direction bottle is180°Nearby1Lower, lower90°270°Nearby1It shows a higher value, and a clear wind direction dependent. We believe that further verification is needed in the future whether it is a phenomenon specific to this site or based on average.

 

Figure 3 The ratio of VL wind speed ((a) scalar average, vector average, vector average -FCR) on the Vane wind direction on the horizontal axis, the CUP wind speed on the vertical axis.

 

4. Summary

In complex terrainVLFor observations, scalar average, vector average, vector average-FcrThe results of the accuracy verification of the data are summarized below.

(1) Follow the NK guidelines,VaneWhenCUPAs a verification value, observationVLAs a result of evaluating the accuracy of wind direction and wind speed observation value, the wind direction is all average method, and the wind speed is the average vector.-FcrOnly the method met the standard.

(2) Among the VL observation values, the scalar and vector average methods are understood by wind speed, and are determined to have an observation error due to the effects of complex terrain. As a result,NKTo meet the guidelines standardsVLIt is considered that some corrections need to be corrected to the observation value.

(3) Vector average-FcrThe method was confirmed that the vector average has been corrected that depends on the wind direction. As a result, it was corrected to the high wind speed side, indicating a better correlation than other average methods on this site.

 

References

1) Japan Maritime Association, 2021: Wind Farm Certificate Remodeling Wind Power Edition(KRE-GL-WFC01Edition: Oct2021)

2) Toshinari Mito, Mizuki Kohana, Hideki Kato, Teruo Osawa, Takumi Tsuji, Susumu Shimada,2018: Consideration for the accuracy of wind status observation using a vertical irradiation type doppler rider, No.40Winding energy usage Symposium proposal collection, pp.191-194.

3) Toshinari Mito, Mizuki Kohana, Hideki Kato,2019: Introducing examples of the accuracy of wind status observation using a vertical irradiation doppler rider on flat terrain, the Japanese Wind Energy Society Magazine43roll2issue, pp.193-196

4) Toshinari Mito, Mizuki Kohana, Hideki Kato, Susumu Shimada, Hisanori Tanaka,2019: Achievements and issues of wind -free observation using doppler rider in powerless areas and complex terrain, No. 141Winding energy usage Symposium proposal collection, pp.199-202.

5) Wind Guard, 2018: Observed Reduction of Sensitivities of WindCube Measurements by Vector Averaging Workshop on Vector Averaging Versus Scalar Averaging

6) IEC 61400-1 (ED-4.0): 11.2 Assessment of the TopologRaphical COMPLEXITY OF THE SITE ATS ETS EFFECT ON TURBULENCE

7) Andrew Hastings-Black, Principles of Hybrid Wind Reconstraction LIDAR WITHOUT LIMITS: Innovative WindCube® Enhancements for Wind Energy Vaisala Webinars

8) Leosphere, WindCube FCR Measurements、〔https://windweb.leosphere.com/windweb/assets/supportDoc/Windcube%20FCR%20measurements%20-%20detailed%20presentation%20(rev1.2).pdf] (Final search date : 2022Year 9 Moon21Day)

9) Annette WesternHellweg, PHILIPPE BEAUCAGE Nick RobinsonRSD Correction for Complex Terrain Effects with the Linear Wind Flow Model Windmap2021-09-08 Wind Resource Workshop Windeurope