Quasi-Distributed Static/Dynamic Strain Detection of Wind Turbine Blades Based on Fibre Bragg Grating Arrays Sensing

This paper presents a quasi-distributed sensing method for wind turbine blade strain using fibre Bragg grating (FBG) arrays. The sensitive area of the blade strain variation is determined by simulation, and three fibre grating arrays are arranged on the surface of the sensitive part of the blade strain. Static experiments show that the strain is larger between 0.6 times blade length (0.6R) and 0.8 times blade length (0.8R), which is consistent with the simulation results. It is also found that the slopes of the strain versus load fitting curves are similar at different angles of attack, but the intercepts are different. The dynamic experiments show that the strain at 0.8 times blade length (0.8R) is the largest and changes most rapidly with time. The dynamic strain distribution is similar to the static experimental results. In this paper, the integration of quasi-distributed strain sensing for wind turbine blades is explored, providing a new fibre optic detection technique for strain monitoring.