Real-Time SHM and Operational Data Fusion for Continuous Monitoring Hybrid Onshore Wind Turbine Towers

This research establishes a robust foundation for developing a structural health monitoring (SHM) approach tailored to onshore wind turbine hybrid towers. A multidisciplinary suite of measurement techniques has been implemented, validated, and assessed to benchmark highly sensitive and cost-effective monitoring strategies. The focus of the paper lies on early-warning damage detection in the transition piece of concrete-steel hybrid support towers. These towers consist of precast concrete ring segments—connected via mortar or mechanical joints—and are anchored using unbonded steel tendons. A transition component links the uppermost concrete ring to the base of the steel tower. A key innovation is the strategic deployment of acoustic emission (AE) sensors at the transition zone. Alarm signals from these distributed sensors are corroborated through sectional cutting force estimations derived from strain gauge data. Furthermore, AE signal energy offers valuable insights into operational states, including loading conditions, power generation, and mechanical behaviors such as pitch angle variations and rotor speed changes. By integrating azimuth measurements and inclination data with acceleration recordings, the methodology enhances early-stage structural assessment, enabling timely maintenance and repair of vulnerable components. This proactive approach supports long-term reliability and maintenance planning throughout the turbine’s service life.