Development of a torque calibration procedure under rotation for nacelle test benches

Abstract

Precise torque measurement in multi-MW nacelle test benches (NTBs) is crucial for the efficiency determination of wind turbines. However, because the torque transducers of NTBs are not yet traceable to national standards, their accuracy is not yet known. To rectify this, a calibration procedure was developed for torque M under rotation using a torque transfer standard. The results of measurements performed on an NTB are presented for a validation and adjustment of the method planned. Different influences on the calibration measurements are discussed, such as static and rotational zero point determination, rotational speed n, and ambient conditions.