A faster and more efficient method of testing wind turbine blades based on thermal imaging has been developed by the Korea Institute of Standards and Science (KRISS). Using cameras from Flir, the new method can identify defects in the metallic and composite materials that make up wind turbine blades quickly and without switching off the generator.
Typically manufactured from advanced composite materials, wind power generation blades are subject to significant amounts of stress that may result in cracks which potentially could result in catastrophic failure.
Test methods for detecting cracks in wind turbine blades have been based on direct contact (requiring generator shutdown) or ultrasonic technology that offers reasonable results but is limited by the considerable time and effort to detect cracks in local areas.
A new thermal imaging test procedure using Flir SC-5000 Series thermal imaging cameras, developed by KRISS, offers the advantages of almost instantaneous results over the whole blade – and non-contact inspection, enabling the test to be undertaken without having to dissemble the blade from the wind power generator.
Having demonstrated the utility and benefits of the thermal imaging method, KRISS is now quantifying the test results and undertaking research to develop a standardised defect test system and method.
Man-Yong Choi, vice president of the Korean Society of Non-Destructive Testing, who is leading the work, said: 'The Flir SC-5000 Series cameras offer particular features that are key for this application such as high sensitivity and high-speed thermal imaging.'
