Foundation Monitoring Offshore Wind Farm Deutsche Bucht

The Deutsche Bucht offshore wind farm (OWF) is located in the German North Sea. The wind farm is located in the German exclusive economic zone and as such requires approval by the Federal Maritime and Hydrographic Agency (BSH). All 31 wind turbines of the type Vestas 8 MW are monitored with a structural health monitoring system from Wölfel.

The main focus of the monitoring system is to indicate all relevant changes in the condition of the support structure at an early stage, thus enabling appropriate measures to be taken to avoid unnecessary deterioration of the support structure and reduce downtime.

The monitoring system is able to evaluate important structural parameters to assess the structural integrity of the support structures. These are primarily natural frequencies, vibration amplitudes, bending and torsional loads, quasi-static inclination, and global structural stiffness.

During operation, the monitoring system is able to provide accurate load numbers on an annual basis, which can then be compared to the annual assumed fatigue damage in the design documents. The monitoring application allows for the identification of wind turbine sites that are suffering from higher stress cycles. Early identification of critical sites enables planning of corrective actions to achieve the minimum lifetime target at each site.

In addition, the monitoring system provides complete documentation of the entire load history of the substructure, which opens up the possibility of a lifetime extension.