Load Monitoring and Lifetime Assessment of Wind Turbine StructuresA wind turbine is one of the industrial structures with the highest vibration loads within its lifetime. It has to withstand up to 250 million load cycles within approximately 20 years. The vibration loads of wind turbines vary considerably depending on the location and operational mode of the wind turbine. Even two wind turbines in the same wind farm may differ significantly in their vibration loads. In the design phase, these loads can only roughly be determined, leading to potential reserves of a turbine’s lifetime during operation. Therefore, the structural monitoring of turbine towers is an essential part of controlling the lifetime of a wind turbine. In current operations on-site, the use of the retrofit solution SHM.Tower reveals that considerable reserves exist, allowing lifetime extension of turbine towers. Furthermore, lifetime-driven operation of wind turbines can be realised by using SHM.Tower, which is energy self-sufficient.
By Dr.-Ing. Carsten Ebert, Dr.-Ing. Manuel Eckstein, Dr.-Ing. Georg C Enss and Dipl.-Ing. Bernd Wölfel, Wölfel Wind Systems, Germany
