Research on wind turbine blade damage based on pre-stressed FBG strain sensors

Abstract

One of the essential parts of a wind power generator that captures wind energy is the wind turbine blade. The safety of the blades rapidly declines as a wind turbine’s operating period grows. For real-time monitoring, a chip-type pre-stressed fiber Bragg grating (FBG) strain sensor was fabricated. The sensor’s structure was improved using simulation analysis along with optimization. It was discovered through calibration trials that the pre-stressing method expanded the sensor’s range of measurement, guaranteed overall linearity, and prevented the potential hysteresis phenomena during compression. The sensor’s final sensitivity was calculated to be 1.970 pm/µε, and its linear fitting coefficient was 0.999. Finally, the sensor was used to monitor the wind turbine blades and the strain change curve of the root of a normally functioning blade is found to be a sine curve, which provides a certain reference value for judging whether the blade is damaged in the future.

References

[[1]] Global Wind Energy Council. 2014 China wind power review and outlook[R]. GWEC, 2014.

[[2]] Global Wind Energy Council. Global wind report 2022[R]. GWEC, 2022.

[[3]] Beganovic N, Söffker D. Structural health management utilization for lifetime prognosis and advanced control strategy deployment of wind turbines: an overview and outlook concerning actual methods, tools, and obtained results[J]. Renewable and sustainable energy reviews, 2016, 64: 68-83,

[[4]] Sun X, Wang Q M, Li Z W, et al.. Abnormal diagnosis of fiber Bragg grating strain gauges in health monitoring system[J]. Optics and precision engineering, 2021, 29(11): 2581-2589,

[[5]] Tan Y G, Chen Y Y, Li R Y, et al.. A substrate-type fiber Bragg grating strain sensor with enhanced sensitivity[J]. Chinese journal of sensors and actuators, 2018, 31(6): 664-669

[[6]] Ren L, Li H G, Hu Z Q, et al.. Development and application of FBG strain sensor with enhanced sensitivity in the model vibration experiment[J]. Journal of optoelectronics-laser, 2008, 19(11): 1437-1441 (in Chinese)

[[7]] Mieloszyk M, Majewska K, Ostachowicz W, et al.. Application of embedded fiber Bragg grating sensors for structural health monitoring of complex composite structures for marine applications[J]. Marine structures, 2021, 76: 102903,

[[8]] Lu L D, Yan G, Liu F, et al.. Joist load test based on pre-stretching substrate FBG sensor[J]. Piezoelectrics & acoustooptics, 2017, 39(4): 619-623

[[9]] Li Z Y, Zhang Z P, Zhang X P, et al.. Research on the sensitivity structure of the substrate fiber grating strain sensor[J]. Optical communication technology, 2018, 42(6): 21-24

[[10]] Peng J, Jia S, Jin Y, et al.. Design and investigation of a sensitivity-enhanced fiber Bragg grating sensor for micro-strain measurement[J]. Sensors and actuators A: physical, 2019, 285: 437-447,

[[11]] Matveenko V P, Shardakov I N, Voronkov A A, et al.. Measurement of strains by optical fiber Bragg grating sensors embedded into polymer composite material[J]. Structural control & health monitoring, 2018, 25(3): 1-11,

[[12]] Du C C, Kong D R, Xu C D, et al.. Design of metallic packaged fiber Bragg grating sensor and its strain transfer experiment[J]. Journal of Hunan University (natural sciences), 2022, 50(4): 9-20

[[13]] Ding C, Liang J C, Yin Y N, et al.. Surface treatment technology for enhancing adhesion between rubber and metal[J]. China synthetic rubber industry, 2013, 36(5): 405-410

[[14]] Kerstin S, Wolfgang E, Jorg A, et al.. A fiber Bragg grating sensor system monitors operational load in a wind turbine rotor blade[J]. Measurement science and technology, 2006, 17(5): 1167-1172,