Value of Structural Health Monitoring (VoSHM) as objective of Genetic Algorithm for Optimal Sensor Placement on Zayas’ Frame.
Source: BAM
The jacket foundations of offshore wind turbines are regularly inspected for potential damage. Through Structural Health Monitoring (SHM) systems, vibration data is continuously captured and analyzed. The extracted information regarding potential global damages to the redundant steel structure can be used in the planning of inspection and maintenance measures. The updated system reliability guides decisions concerning inspections and repairs.
The installation and operation of the monitoring system incur costs, which, combined with expenses from inspections, repairs, and the risk of system failure, constitute the overall costs over the structure's lifespan. Employing an efficient sensor selection for the monitoring system via a Value of Information (VoI) analysis helps optimize the costs and benefits. The task, therefore, lies in maximizing the potential benefits of the system for monitoring dynamic structural responses before its commissioning. In this work, a genetic algorithm is being tested to determine the optimal placement of vibration sensors.
This framework is demonstrated on a redundant jacket-like steel frame. The numerical example illustrates that the benefit of the monitoring system for risk-based inspection and maintenance planning generally outweighs the costs. After a few optimization steps, the sensor configuration with the highest value for the structure's lifetime management is identified. Depending on the cost model reflecting offshore conditions during sensor installation and operation, monitoring systems consisting of a few sensors in the upper part of the structure exhibit the best cost-benefit ratio.
The genetic optimization algorithm for sensor placement performs well compared to sequential algorithms, offering significant potential for applying these methods to real jacket foundation structures. The next step involves applying the concept to a downscaled three-legged jacket to assess the framework’s practicality. The goal is to contribute to enhancing the lifetime management of offshore wind turbines, thereby advancing the transition to renewable energies.
Optimal vibration sensor placement for jacket support structures of offshore wind turbines based on value of information analysis
Lukas Eichner, Ronald Schneider, Matthias Baeßler
published in Ocean Engineering, volume 288, issue 2, essay number 115407.
BAM Safety of Structures
BAM Buildings and Structures