TY - CONF A1 - Hu, Wei-Hua A1 - Rohrmann, Rolf A1 - Said, Samir A1 - Rücker, Werner A2 - Xu, Y. L. A2 - Zhu, S. A2 - Xia, Y. A2 - Ni, Y.Q. A2 - Law, S.S. A2 - Yin, J. H. A2 - Su, Z.Q. T1 - Development of a vibration-based structural health monitoring system for wind turbines T2 - SHMII-6 - 6th International conference on structural health monitoring of intelligent infrastructure (Proceedings) N2 - In the context of national innovative project IMO-WIND, an integrated long term monitoring System was installed on a prototype of an offshore wind turbine System of 5 megawatt dass. The Federal Institute for Materials Research and Testing (BAM) was responsible for development of the SHM System. It consists of a signal acquisition System and a Signal processing and management System. The signal acquisition System is composed of 14 acceleration sensors, 110 strain gauges and 4 inclination sensors, installed at the tripod foundation and the tower. It began to work in August 2007. In order to investigate the structural dynamic properties, extract efficient damage index and manage huge amounts of Vibration Signals and analysis results, an automated signal processing and management Software System is developed in LabVIEW® environment. It includes functions such as automated Operational Modal Analysis (OMA) on the basis of Stochastic Subspace Identification (SSI) method and poly-reference Least-Squares Complex Frequency Domain (p-LSCF) approach, investigation of environmental/operational effects on structural dynamic properties under operational conditions, features extraction using Principal Component Regression (PCR) and Multiple Linear Regression (MLR) as well as data/result management and visualization. Besides, this paper also presents variations of structural modal parameters of a wind turbine system under complex environmental/operational conditions. Comparison of modal parameters automatically extracted by SSI method and poly-reference p-LSCF approach indicates that the latter method provides more stable modal identification results ffom the viewpoint of long term OMA. Subsequently, the influences of temperature, wind velocity, rotation speed and nacelle direction on modal parameters are generally discussed. Finally, variations of indentified modal parameters during two years are presented. T2 - SHMII-6 - 6th International conference on structural health monitoring of intelligent infrastructure CY - Hong Kong, China DA - 09.12.2013 KW - Wind turbine KW - Vibration-based structural health monitoring system KW - Automated operational modal analysis KW - Environmental and operational effects KW - Feature extraction KW - Damage detection PY - 2013 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/32973 AN - OPUS4-32973 SN - 978-962-367-768-4 SP - 1 EP - 10 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany