Approaches to Acoustic Emission Monitoring with Applicability to Key Components in Wind Turbines

Abstract

The operation of wind turbines is complex with possible failure mechanisms arising from a variety of structures and mechanical systems, such as the blades or gearboxes and drive systems. The scale of deployment of wind turbines continues to grow and they are deployed in increasingly remote and difficult to access areas; making their inspection and maintenance a challenging and costly activity. The use of effective structural health monitoring (SHM) systems can offer operators the potential to reduce down time and save costs. Acoustic emission (AE) is a sensitive and passive damage detection technique that can offer low power, continuous monitoring of structures and systems, as well as the potential to locate damage. As such it is well suited for use in SHM applications. In this paper the authors will present two distinctly different applications of AE to SHM, with strong applicability to wind turbine structures. Firstly a novel approach to source location is used to improve accuracy in anisotropic composite materials. Secondly, an approach for monitoring rotating machinery that utilises continuous AE wavestream data is presented, thus demonstrating that a single technology can be used to monitor differing elements of a turbine and allow the simplification of a global SHM system.