Case Study 8: Structural Health Monitoring

EnerOcean has designed a SHM system for blades and other submerged key components of Marine Energy converters. The solution was proven in January 2021 during a test campaign of a tidal blade subjected to several loading cycles until its breakage.

EnerOcean has grouped its data collection into two groups:
• Strain gauges data, which are acquired in real time during loading cycles.
• Ultrasonic tests (LRUT), which are collected in static.

The system installed for this data campaign consists of two subsystems. The information provided by each of them is supplemented for its analysis before, during and after load testing.

Nine measurement points have been chosen to locate piezoelectric sensors for ultrasonic emission and strain gauges. The chosen measurement points are shown below.

At each measurement point, a sensor type is installed for each system and protected with a custom-designed package.

The tests distribution of the blade and the strain gauges/deformation equipment have been performed according to different loads, maintained and cyclical tests until blade breaks.