Posters

Abstract

* Introduction: Nacelle-mounted lidar (NML) technology is increasingly leveraged for Power Performance Testing (PPT) of onshore and offshore wind turbines. In the past years, several calibration and measurement procedures have been developed for the use of NML for turbine performance verification. These procedures paved the way for the new IEC 61400-50-3 standard which has been officially released in January 2022. Together with IEC 61400-12-1, this standard provides the industry with extensive guidelines for the use of NML for PPT. This contributes to the acceptance of NML as a go-to wind measurement technology for onshore and offshore turbine performance verification. For a NML to fully comply with the IEC-50-3 standard, a third-party classification has to be passed, including: 1. Sensitivity study: assessment of the NML intermediate values (line of sight speed - LOS speed) sensitivity to environmental variables 2. Evidence base: datasets of several field tests supporting the accuracy of the WFR (Wind Field Reconstruction) model. This presentation will highlight the results of the first Nacelle Mounted Lidar Classification as per IEC 50-3. This classification has been performed by Vaisala and DNV for the WindCube Nacelle (WCN). * Method: A WindCube Nacelle PPT lidar was sent to DNV's calibration site in Janneby (Germany). 1. Sensitivity study: The results of the LOS calibration against cup anemometers mounted on IEC met masts were used for the sensitivity study. 2. Evidence base: In order to fulfill the IEC criteria, a minimum of five “on-nacelle” and “off-nacelle” tests are required per IEC 50-3. Results from previous WCN field measurement campaigns have been used to build the evidence base: 2 datasets from “on-nacelle” tests: lidar mounted on a normally-operating wind turbine; 4 datasets from “off-nacelle” tests: lidar mounted on the ground or on a fixed platform. * Results: First, results of the sensitivity study will be presented. The list of significant and non-significant environmental values will be detailed as well as the associated “classification uncertainty”. An example of how those results can be used in real measurement campaigns using WCN will be presented. Second, results of the evidence base analysis will be presented. Results of on-nacelle and off-nacelle tests proving the accuracy of the WCN wind field reconstruction algorithm as per IEC 50-3 will be presented. * Conclusion: The newly released IEC 50-3 standard is contributing to the acceptance of NML as a go-to measurement technology for offshore and onshore wind turbine power performance testing. With this breakthrough classification, WindCube Nacelle becomes the first nacelle lidar to be fully compliant with this new industry standard - confirming the system suitability and reliability for accurate power curve verification. * Learning objectives: The delegate will learn about the results of the WindCube Nacelle classification as per IEC 50-3 done by DNV and Leosphere. The delegate will learn about how the classification results could be used for a real measurement campaign. The delegate will learn about the accuracy of WindCube Nacelle measurements. The authors hope that these results will bring useful information to the wind energy community and promote the usage of NML for PPT.