SIMPLE LOW-FREQUENCY OPTICAL-FIBER ACCELEROMETER WITH LARGE ROTATING MACHINE MONITORING APPLICATIONS

A simple fiber optic accelerometer with large rotating equipment monit oring applications is presented. The sensor is optimized for detection of mechanical vibrations in the frequency range 0.2-140 Hz, The minim um detectable acceleration is 0.025 m/s(2) root mean square (rms), and it has low-transverse sensitivity The transducer operating principle, based on a fiber optic cantilever beam without any seismic mass on it , is simple and easy to construct, and the intensity-modulation and co mpensation techniques developed require simple electronic processing a nd provide very good stability and accuracy, Other advantages of the s ystem are its robustness, compact size, and cost-effectiveness, which make it appropriate for industrial applications, specially for those w here harsh environments are involved, The complete process of research and development of the sensor has been carried out, from the theoreti cal study of its operation principles, through the design, fabrication , experimental characterization and enhancement, to its starting up in a high-power electric station for hydrogenerator monitoring.