The Vibration Detection System Based On FBG Acceleration Sensor

Vibration detection has very important research significance and application value,such as in the power system,the vibration of transformer and transmission line can be detected to discover hidden dangers of accidents and avoid economic losses;in large civil engineering structures and infrastructures,the vibration detection of structure can play to assess the health status of itself;in a variety of large-scale machinery and equipment,the vibration detection of equipment can monitor the running state of equipment,we can timely have maintenance or repair for the equipment.With the development of optical fiber technology and communication technology of optical fiber,optical fiber sensing has attracted much attention in the sensing field.It has high precision,strong anti electromagnetic interference ability and on-line monitoring and other advantages,which constantly was favored by researchers,and gradually applied in the field of engineering.The vibration detection system designed in this thesis using fiber Bragg grating(FBG)sensor as sensor,broadband light source and F-P tunable filter produced tunable laser,and tunable filter was controlled by F-P.The laser wavelength is located in the edge of FBG reflection spectrum.On this basis,STM32 is used to generate control DAC to generate adjustable constant voltage.After amplification,it is used to drive F-P filter.By detecting the change of signal power reflected by FBG,the vibration detection system complete the detection of vibration signal.At the same time,data acquisition is carried out by DAQ-2010 data acquisition card of Linghua technology company.And upper monitor software is developed by LabVIEW programming language.The vibration signal is analyzed and stored by the upper monitor.In this thesis,the dynamic drift characteristic of the F-P cavity filter is analyzed.The experiment shows that the dynamic drift characteristic can be weakened by preloading the voltage in advance.Finally,the fiber Bragg grating vibration detection system is compared with the electric vibration detection system of the Jiangsu Donghua test technology company.The results showed that for the fiber grating vibration measurement system in this thesis,the vibration frequency measurement results of relative error less than 3% within the scope of 100 Hz.The maximum acceleration measurement results can be stable fall within the scope of comparative measurement,the results above indicate that vibration detection system based on fiber grating is effective.