Low-Cost Tower Root Fatigue Load Estimation for Structural Health Monitoring of Grouted Connections in Offshore Wind Turbines

Abstract:

The sinking of wind turbines (WTs) with monopile foundations is one of the major issues in the offshore wind industry nowadays. Dynamic wind and wave loads act on the WTs causing vibrations of the structure. However, grouted connections in the monopiled WTs are not designed well enough to transfer bending moments from the wind loading. When the load capacity of the grouted connection is reached, stress cracks appear in the grout causing transition piece to slide down. Direct measuring of the fatigue load, called the tower bending moment, causing fatigue failures and sinking of the WTs is expensive and practically unfeasible. This paper suggests a low-cost, model-based algorithm for indirect measuring of the tower bending moments from the WT dynamic response measurements. The bending moment is estimated recursively using well-known Kalman filter theory. The method is validated using WT simulated data, assuming different measurement noise levels.

• Periodical: Key Engineering Materials (Volumes 569-570)
• Pages: 676-683
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.569-570.676
• Online since: July 2013
• Authors: Nevena Perišić, Poul Henning Kirkegaard
• Keywords: Grouted Connection Problem, Kalman Filter (KF), Load Estimation, Tower Bending Moment

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