A Surface Strain Monitoring Technique for Slope of Mountainous Area Substation Based on FBG Sensor

Abstract

Geological structure health in mountainous area substation is complex, and the climate is changeable, it is easy to appear the geological disasters like landslide and subsidence in substation, Aiming at the strong electromagnetic interference in substation and other factors, to monitor of slope surface strain of mountainous area substation with FBG strain sensor, in order to reflect the stability of the slope. Combined with the actual situation of slope of Yunnan 220kV mountainous area substation, the surface type FBG strian sensors are installed on the surface of upstream and downstream slope of mountainous area substation, the lower reaches of the substation, the serial network forms a quasi distributed optical fiber sensing network. they form a quasi-distributed optical fiber sensing network through the serial networking methods.When the slope surface occurs deformation due to the soil sliding, it will drive the FBG strain sensor and transfer the equal strain to the FBG strain sensor. By measuring the center wavelength shift of the FBG strian sensor, the strian value of slope surface at each point can be reflected. The monitoring results show that, the period from May 9th to June 6th, the maximum strain of upstream slope is 171uɛ, it appears at the location of marked as US4 FBG strain sensor, the maximum strain of downstream slope is 112uɛ,it appears at the location of marked as DS1 FBG strain sensor.