Comparison and validation of wake models based on field measurements with lidar

Abstract

Power loss caused by wind speed deficit in wind turbine wake is a critical issue for wind farms. Various engineering wake models have been developed and applied to predict velocity distribution in wind turbine wake and wind farm power production. In this study, three widely used wind turbine wake models, Jensen, Frandsen and Larsen model, were compared and validated, in order to find out prediction accuracy differences between them and know how to best utilize them. The calculate results were compared with field measurement data with lidar. A series of wind tests on single wake were conducted using a lidar in an onshore wind farm in the northwest of China. Two scan types, plan position indicator (PPI) scans and velocity-azimuth display (VAD) scans, were implemented, and wind speed data in a single wake region was measured. The comparison and verification results show that three models all underestimated the velocity deficit in this case, and higher prediction accuracy appears in the far wake zone.