Fiber Optic Ae Sensing System Research And Application

Acoustic Emission means the phenomenon that partial fast release energy with the transient elastic wave in different materials, sometimes it is also called stress wave emission. Acoustic emission technology includes instrument examination, signal analysis toward acoustic emission using sound transmitting message inference sound launch source technology.Along with computer and signal processing technology's rapid development, acoustic emission technology becomes much more mature than before, its application scope covers nearly all national economic domains includes aviation, astronautics, petroleum chemical industry, railway and automobile, civil buildings and electric power plant and so on.Acoustic emission examination is one of non-destructive measuring technology, which examine the flaw or latent flaw occupies in the secular variation process of component or internal structure.The explaination of the structure internal flaw change is a complicated process according to the electrical signals of AE, it need coordination of rich knowledge and other experimental method. On the other hand, acoustic emission examination environment suffer of serious noise interference frequently, although there are many kinds of noise elimination methods, AE application of certain situation is serverly restricted. Traditional PZT ultrasound sensor suffer of serious electro-magnetic interference, its validity receives server restriction under strong electric-magnetic field. Regarding optic fiber sensor's vital significance, people have carried on exploration as well as different sensing mechanisms in past several years.This paper analyze different kinds of acoustic emission measuring methods and importantly introduced optic fiber AE measuring system based on over coupled fused coupler.This paper introduces each part's constitution and principle in detail and studies the relationship between the whole system's response and photosource type, output power, probe sealing form, demodulation design. Finally, We carry on laboratory test and power transformer shelf depreciation field test to the entire optic fiber AE measuring system.This paper's innovation lies in the application of optic fiber sensing technology on acoustic emission measuring. The optic fiber AE measuring system developed in this paper offers advantages of miniaturization, wideband working, anti-electromagnetic interference, intrinsically safe. It owns significant guiding sense towards realization in the industrial AE measuring application.