Research On Transmission Method And Characteristic Of Rotating Machinery Noncontact Optical Fiber Signal

With the rapid development and innovation of optical fiber sensing technology,that has opened up a new testing principle and detection method for the state and fault monitoring of the mechanical system. Fiber grating detection technology has been applied to running real-time monitoring of large-scale rotating machinery occasions such as steam turbine. In order to meet the needs of connection information between the rotating machine platform and the monitoring system equipment in monitoring optical path, required to fiber optic rotary joint device, to achieve efficient and stable fiber optic signal transmission between the high speed of the rotor and the stationary detection equipment. Support by the national science and technology projects "863" and college students' independent innovation fund, this thesis carried out the research on transmission method and characteristic of rotating noncontact single-channel fiber-optic signal for rotating machinery.From the analysis of the rotating optical fiber signal transmission loss, put forward specific performance indicators for fiber-optic signal transmission of rotation. And comparative analyzed technical parameters and coupling loss of several commonly used fiber collimator device, analyzed and derived the theoretical formula of The affection to coupling loss by three collimator assembly errors, and obtained the impact curves by experiment; Based on the theoretical research of optical path loss and the status of development at home and abroad, proposed and designed a new type of single-channel fiber-optic signal transmission isolation adaptive rotation Connector(hereinafter abbreviated: Adaptive rotary connector), specifically addressed its working principle, structural design and innovation, analyzed the adaptive optical rotary joint transmission loss. The design has been patented(CN 203595833 U).Developed a kind of adaptive rotation connector object based on the theoretical analysis, and designed assembly and debugging experiment to test its performance, obtained the experimental results that was fit to the theoretical research and verified the credibility and stability of the adaptive rotation connector; Set up a platform for torsional vibration test and carried out experimental research of the adaptive rotation connector using Fiber Bragg grating test method, then analyzed the optical signal transmission characteristics and method under the laboratory environment, and conducted the comparative study with double collimator coupling test system, proved the adaptive rotation connector can meet the function for rotating optical signal transmission and detection of the torsional vibration test platform, finally revealed the merit and demerit of the double collimator coupling and adaptive rotary connector test system.Relative to the laboratory environment, selected t the turbine rotor for the study of adaptive rotary connector applied to the actual working conditions; build a real-time condition monitoring platform of steam turbine rotor. Introduced the structure of the monitoring platform, test methods and rotating optical path design. Comparative studied three rotation optical signal transmission schemes, including the double collimator coupling, Optical fiber slip ring, adaptive rotary connector. Demonstrated the feasibility of adaptive rotary connector in practical applications. By contrast the merits of the three schemes, reveals the optical signal rotation transmission scheme selection principle under different working conditions.The research in this thesis has vital significance in developing fiber optic rotary joint device with self intellectual property rights, enriching methods and characteristics of fiber optic signal rotation transmission and enhancing the level of state monitoring of large rotating machinery in our country.