The mistralwind project-towards a remaining useful lifetime analysis and holistic asset management approach for more sustainability of wind turbine structures

In the near future more and more onshore wind turbines will reach the end of their designed service life of twenty years. From an economic and operational perspective, it can be profitable to prolong the operational activities beyond the original design life. In particular, turbines in the megawatt class bear technical and economical reserves, which should be yielded for more sustainability of wind turbine technology. Prospectively it might be possible to operate wind turbine structures longer than thirty years with a service life optimizing operation and maintenance strategy. The MISTRALWIND project (acronym for Monitoring and Inspection of Structures of Large Wind Turbines; partners: IABG Industrieanlagen-Betriebsgesellschaft mbH, Technical University Munich, Siemens AG) focusses its research activities on developing innovative and reliable methods and sensor systems for analyzing the remaining useful lifetime (RUL) capacities of a wind turbine structure. The paper is aimed at giving an overview of the first project results in the areas of FEM-modeling, wired and wire-less sensor technology, non-destructive testing techniques, fatigue mechanisms and integrating information from monitoring and inspection into the turbine's controller, and probabilistic models for optimized operation and maintenance strategies for wind turbines. The methods developed here can be transferred to other structural systems - e.g. civil engineering structures or aerospace structures - to optimize their operation and maintenance strategy.