关键词: Mach-Zehnder干涉仪, 光纤传感, 薄壁增敏电缆套筒, 有限元分析, 电网舞动检测器

Abstract: Aiming at the problems of weak electromagnetic interference immunity, continuous external power supply, complex installation process, low signal-to-noise ratio, and insufficient sensitivity of conventional power grid dance monitoring systems, we proposed a novel cable disturbance monitoring system. The system employed a dual-ended Mach-Zehnder interferometric (MZI) optical path structure, which could achieve long-distance, large-scale, and multi-dimensional online monitoring and structural safety warning to locate the position of the dance in real-time. The sensor core adopted a thin-walled sensitivity-enhanced cable sleeve design, which integrated a laser MZI optical path composed of high-sensitivity micro-optical fiber and couplers inside. This interferometer had excellent response characteristics to vibration. After being encapsulated within a specialized metal housing to form an integrated dance monitoring sensor. The experimental results show that the natural frequency of the finite element of the sensor is 106.77 Hz, and the relative error with the measured date is only 1.65%. The relative sensitivity of the detector in the range of 0—140 Hz is 41.25—66.78 dB(rad/Pa), which confirms its ability to detect the high sensitivity of the dance signal.

Key words:  , Mach-Zehnder interferometer, fiber optic sensing, thin-walled sensitivity-enhanced cable sleeve, finite element analysis, power grid
 , dancing detector