Power Curve Verification in complex terrain using multi- range nacelle lidars

Power curve verification in complex terrain has always been a challenge. The current IEC standard requires a preliminary site calibration using two met masts - which can be difficult to carry out, expensive and gives a large unertainty to the measured power curve. In the UniTTe project we have developed and tested an alternative procedure using a nacelle mounted lidar. By measuring closer to the rotor, the influence of the terrain on the inlfow can be neglected whereas the wind speed slow down due to the induction is corrected for using a simple analytical model. In this presentation, results of 3 measurement campaigns are shown ( 1 in flat terrain and 2 in complex terrain) demonstrating the potential of this approach for power curve verification without site calibration.