Fabrication and Test of a Low-Cost Intensity-Based Optical Fibre Accelerometer for Wind Turbine Blade Monitoring Application

Abstract

The paper presents the fabrication and testing of a low-cost fibre optic accelerometer designed for wind turbine monitoring. The accelerometer was fabricated using plastic optical fibre enclosed in a plastic casing made from 3D printing. Nine fabricated accelerometers were mounted along a cantilever beam w a non-rotating wind turbine blade under wind excitation. An output-only non-model based approach namely NExT (Natural Excitation Technique) and ERA (Eigensystem Realization Algorithm) were chosen for modal analysis of the cantilever beam. The fibre optic accelerometers produced comparable time response, mode shape and damping ratio with the reference piezoelectric accelerometers in terms of amplitude and accuracy.