Research On Key Technologies Of Fiber-optic Displacement And Stress Sensors

With the rapid development of society,the requirements for the safe and stable operation of transmission lines in the power industry have gradually increased.Intelligent monitoring of safety performance is currently the most difficult problem.In the field of precision automation instruments and intelligent equipment,high-precision,high-reliability sensors are increasingly demanded in today's production and scientific research environments.Due to the current detection technology,most of them have the disadvantages of weak electromagnetic interference,low sensitivity and high cost.Therefore,such new sensors with strong anti-electromagnetic interference capability and high precision have great application value and research significance.Based on the development and advantages of optical fiber sensing technology,this paper mainly introduces the key technologies of optical fiber displacement and stress sensors in detail.The main research work and research results of this paper are as follows:1.A new method for optimizing displacement sensors is proposed.The correlation between the resolution of the displacement sensor and the resolution of the grating and the resolution of the spectrometer and a series of experiments verify the effectiveness of the optimization method.A suitable grating linear density formula is selected and the optimized experimental results are compared to obtain a large range and high resolution displacement sensor.2.Research the main core component of optical fiber stress sensor-cantilever beam.Through the stress analysis and material selection of the cantilever beam,combined with the analysis of the corrosion resistance,elasticity and cost of the material,the stainless steel material was finally selected.At the same time,three special cantilever beam structures are proposed to compare the simulation results,and the triangular structure has the largest strain.The combination of cantilever beam and fiber grating technology is used to increase the strain of the cantilever beam and the wavelength change of the fiber grating.3.A new type of optical fiber type stress sensor with triangular cantilever beam structure is designed.Several software simulations and experiments have been carried out on the triangular cantilever beam structure to verify that the new structure has good linearity,recovery and reliability.The sensitivity optimization design scheme was further carried out for the structure,and the performance of the optimized optical fiber stress sensor was improved by seven times.