基于BOTDR的海缆3D立体监测系统设计与实现

Design and realization of the submarine cable three-dimensional monitoring system based on BOTDR

海底电缆体积大、造价高,铺设在海底导致日常巡检和故障检测非常困难,目前尚无有效的实时在线监测系统。针对该问题,采用基于布里渊光时域反射(BOTDR)技术进行海底电缆实时在线监测,利用海底电缆复合光纤作为传感元件,该监测方法不仅可以监测海底电缆沿线每一点的温度分布,还可以测量海底电缆所受外力的情况。在理论分析以及对G.652光纤进行温度和应变系数标定的基础上,在国内外首次将BOTDR技术应用到真实海底电缆在线监测,并将BOTDR系统、船舶自动识别系统和视频监控系统相结合,设计并实现了110 kV三相单芯高压光电复合海缆的三维立体在线监测系统,且详细分析了BOTDR测试获取的海缆温度和应变数据。该系统不仅可以实现海底电缆运行状态的实时在线监测,还可以对引起海缆故障的肇事船舶进行录像、定位和确认,为事故赔偿奠定了坚实基础。在福建省电力公司12个月的良好稳定运行及数据初步分析结果表明了本系统的有效性。

Daily inspection and fault detection of submarine cable is very difficult because of its large scale,high cost and lying under the ocean.At present,there is no effective real-time on-line monitoring system.To solve this problem,we adopt the Brillouin optical time domain reflectometer （BOTDR） technology to conduct the real time on-line monitoring of the submarine cable.Taking the fiber composite in the cable as a sensor,the BOTDR monitoring method can measure the temperature distribution as well as the external forces exerted on the submarine cable along the submarine cable.On the basis of theoretical analysis and the temperature and strain coefficient calibration of the G.652 optical fiber,the BOTDR technology was applied to the real submarine cable on-line monitoring for the first time both at home and abroad.Furthermore,combining the BOTDR system,ship automatic identification system （AIS） and video monitoring system together,a three-dimensional on-line monitoring system of 110 kV three-phase single core high-voltage submarine power and optical fiber composite cable was designed and implemented.The strain and temperature data obtained with BOTDR were analyzed in detail.The system not only can realize the real time on-line monitoring of the submarine cable operation status,but also can record,locate and confirm the ship causing accident,which provides a solid evidence for accident compensation.The twelve month stable operation in Fujian Electric Power Supply Company and the preliminary data analysis reveal the effectiveness of the system.