The Eolic sector had shown promising developments and has been predicted to reach 40.6% of all renewable electricity according to a European Commission report. With almost 20% of the manufacturing costs of a wind tower is spent on the turbine blades alone, it is important to carry out regular maintenance of this major component.
Current inspection techniques involve the use of visual, ultrasound or thermography images to maintain the structural integrity of a wind turbine blade and optimise its life span. However, these methods can be time consuming, dangerous and expensive because it either requires sending a person to work at height or dismantling the WTB for close-up defect detection. Therefore, TWI together with its leading partners LSBIC, Gamesa, Innora and WRS had come up with an innovative solution to develop an automated system that will be deployed by a robot and remotely controlled by an operator on the ground. It will be able to climb a wind tower and carry out Non-Destructive inspection of the WTB by means of a shearography unit with thermal stressing.
The PhD study will be focused on developing advance algorithms which will automatically identify the location, depth, and size of the defect within the WTB. This will effectively reduce the operator’s burden on interpreting the huge amount of images captured by the shearography unit. Overall, the technology offers significant reduction in inspection time, sub-surface defect detection and more importantly the avoidance of working at height during WTB inspections.