In-service wind turbine blade monitoring

Abstract

Monitoring wind turbine blades for damage onset and progression detection in efficient and effective ways can be one of the most challenging tasks for wind site managers, technicians, and fleet engineers. Blades are susceptible to damage from a variety of causes and sources, ranging from environmental factors such as lightning to normal wear-andtear leading to worsening leading edge erosion, crack propagation and internal delaminations. With these defects often out of sight, particularly with inspections only being conducted once a year or less, staying fully aware of true blade integrity is often not as efficient a process as it could be. Acoustic Emission (AE) technology is a passive non-destructive monitoring technique that has been successfully used developed to help solve some of the most challenging tasks in the wind energy sector and helping customers stay aware of the integrity of wind turbine blades while maximizing turbine uptime. The MISTRAS solution offers a unique solution for blade integrity management through 24/7/365 remote monitoring and data reporting. MISTRAS combines industry-leading Acoustic Emission (AE) technology with an easily accessible data portal to help protect your blades at every phase of their operations. This work will present a background on the work that has been conducted to enable the technique to be successfully applied. Case studies of real, in-service applications will be presented along with examples of the types of defects detected. This work will present a novel AE monitoring system that has been constructed by MISTRAS for the sole purpose of wind turbine monitoring. An overview of the data acquisition system and sensors are presented followed by the data communications and analytics. Case studies on that demonstrate damages that have been identified of the system in operation are also presented, demonstrating the ability of the system to detect damage early and direct maintenance operations.