Sequence Time Domain Reflectometry (STDR) have been demonstrated to be a powerful technique for detecting the length of cable or length of open circuit or short circuit cables. Using this method along with using smart...Sequence Time Domain Reflectometry (STDR) have been demonstrated to be a powerful technique for detecting the length of cable or length of open circuit or short circuit cables. Using this method along with using smart meter on the main electrical panel board to monitor consumption if load at each circuit, enable user to monitor power consumption at each node (power outlet) only by operating a smart digital meter and an STDR circuitry on each circuit at the main electrical panel board. This paper introduces this method and examines it on dead-wire and energized wire with a load connected across it. Experimental results are demonstrated for both types. Test result show the potential application of this approach to provide consumption information and potential cost saving via feedback for users.展开更多
Yuhuangge （玉皇阁） landslide in Wushan （巫山）, Chongqing （重庆）, is one of the focal monitoring geological hazards in the Three Gorges Reservoir. Time domain reflectometry （TDR） and in-place inclinometers were...Yuhuangge （玉皇阁） landslide in Wushan （巫山）, Chongqing （重庆）, is one of the focal monitoring geological hazards in the Three Gorges Reservoir. Time domain reflectometry （TDR） and in-place inclinometers were arranged to monitor the deep deformation. Time domain reflectometry is based on transmitting an electromagnetic pulse into a coaxial cable grouted in rock or soil mass and watching for reflections of this transmission due to cable deformity induced by the ground deformation. Comparing the monitoring data of No. 5 Station, in the middle profile of the landslide, from June to December of 2008, the depth of slip surface determined by TDR is -33.58 m, which is consistent with the geological condition of the borehole nearby. The deformation curve trend of the TDR and inclinometer is similar, and it is uniform with the deformation caused by the Three Gorges Reservoir 175 m experimental impoundment. Further, TDR can monitor the tiny deformation accurately. Therefore, TDR is applicable to monitor the Yuhuangge landslide deep deformation and reflect the deformation characteristics well. It is significant to promote the application of TDR in landslide monitoring.展开更多
We propose a technique for chromatic dispersion monitoring based on optical time domain level monitoring. Experimental and simulation results show that the technique is effective for the monitoring of dispersion in 42...We propose a technique for chromatic dispersion monitoring based on optical time domain level monitoring. Experimental and simulation results show that the technique is effective for the monitoring of dispersion in 42.7-Gbps CS-RZ signals for dynamic dispersion compensation.展开更多
针对风电机组滚动轴承工作环境恶劣、工况多变且振动信号成分复杂等特点,将33项时域和频域特征参数及其特性应用于风电机组滚动轴承状态监测和故障诊断中,利用奇异值分解重构法(Singular Value Decomposition,SVD)将滚动轴承振动故障信...针对风电机组滚动轴承工作环境恶劣、工况多变且振动信号成分复杂等特点,将33项时域和频域特征参数及其特性应用于风电机组滚动轴承状态监测和故障诊断中,利用奇异值分解重构法(Singular Value Decomposition,SVD)将滚动轴承振动故障信号中的噪声等干扰成分去除,降噪重构后的信号经过基于经验模式分解法(Empirical Mode Decomposition,EMD)的希尔伯特-黄变换,实现故障冲击信号的共振解调处理,将低频周期故障调制信号筛选出来,最终结合滚动轴承各部件故障特征频率、振动信号时频分析结果和时频特征参数诊断结果实现滚动轴承的状态监测和故障识别。并通过振动测试信号分析,验证了该方法对提取风电机组滚动轴承故障特征的有效性。展开更多
随着现代社会对电力系统稳定性和效率的要求日益提高,光纤通信技术在远程电力监控系统中的应用变得尤为关键。文章从光纤通信的基本原理出发,对比分析光纤与传统电缆的优势,并详细分析光纤在数据传输高效性、实时监控和故障检测等方面...随着现代社会对电力系统稳定性和效率的要求日益提高,光纤通信技术在远程电力监控系统中的应用变得尤为关键。文章从光纤通信的基本原理出发,对比分析光纤与传统电缆的优势,并详细分析光纤在数据传输高效性、实时监控和故障检测等方面的应用。此外,深入讨论光纤监控系统中远程光纤测试系统(Remote Fiber Test System,RFTS)、光时域反射仪(Optical Time Domain Reflectometer,OTDR)以及地理信息系统(Geographical Information System,GIS)等关键组件的作用和功能。文章全面概述光纤通信在远程电力监控系统中的应用,强调光纤通信技术对于提高电力系统运行效率和可靠性的重要性。展开更多
文摘Sequence Time Domain Reflectometry (STDR) have been demonstrated to be a powerful technique for detecting the length of cable or length of open circuit or short circuit cables. Using this method along with using smart meter on the main electrical panel board to monitor consumption if load at each circuit, enable user to monitor power consumption at each node (power outlet) only by operating a smart digital meter and an STDR circuitry on each circuit at the main electrical panel board. This paper introduces this method and examines it on dead-wire and energized wire with a load connected across it. Experimental results are demonstrated for both types. Test result show the potential application of this approach to provide consumption information and potential cost saving via feedback for users.
基金supported by the National Natural Science Foundation of China (No. 40672189)the Ministry of Land and Resources of China (No. SXJC-3ZH1D1_[2009]003)the National Basic Research Program of China (973 Program) (No. 2011CB710605)
文摘Yuhuangge （玉皇阁） landslide in Wushan （巫山）, Chongqing （重庆）, is one of the focal monitoring geological hazards in the Three Gorges Reservoir. Time domain reflectometry （TDR） and in-place inclinometers were arranged to monitor the deep deformation. Time domain reflectometry is based on transmitting an electromagnetic pulse into a coaxial cable grouted in rock or soil mass and watching for reflections of this transmission due to cable deformity induced by the ground deformation. Comparing the monitoring data of No. 5 Station, in the middle profile of the landslide, from June to December of 2008, the depth of slip surface determined by TDR is -33.58 m, which is consistent with the geological condition of the borehole nearby. The deformation curve trend of the TDR and inclinometer is similar, and it is uniform with the deformation caused by the Three Gorges Reservoir 175 m experimental impoundment. Further, TDR can monitor the tiny deformation accurately. Therefore, TDR is applicable to monitor the Yuhuangge landslide deep deformation and reflect the deformation characteristics well. It is significant to promote the application of TDR in landslide monitoring.
文摘We propose a technique for chromatic dispersion monitoring based on optical time domain level monitoring. Experimental and simulation results show that the technique is effective for the monitoring of dispersion in 42.7-Gbps CS-RZ signals for dynamic dispersion compensation.
文摘针对风电机组滚动轴承工作环境恶劣、工况多变且振动信号成分复杂等特点,将33项时域和频域特征参数及其特性应用于风电机组滚动轴承状态监测和故障诊断中,利用奇异值分解重构法(Singular Value Decomposition,SVD)将滚动轴承振动故障信号中的噪声等干扰成分去除,降噪重构后的信号经过基于经验模式分解法(Empirical Mode Decomposition,EMD)的希尔伯特-黄变换,实现故障冲击信号的共振解调处理,将低频周期故障调制信号筛选出来,最终结合滚动轴承各部件故障特征频率、振动信号时频分析结果和时频特征参数诊断结果实现滚动轴承的状态监测和故障识别。并通过振动测试信号分析,验证了该方法对提取风电机组滚动轴承故障特征的有效性。
文摘随着现代社会对电力系统稳定性和效率的要求日益提高,光纤通信技术在远程电力监控系统中的应用变得尤为关键。文章从光纤通信的基本原理出发,对比分析光纤与传统电缆的优势,并详细分析光纤在数据传输高效性、实时监控和故障检测等方面的应用。此外,深入讨论光纤监控系统中远程光纤测试系统(Remote Fiber Test System,RFTS)、光时域反射仪(Optical Time Domain Reflectometer,OTDR)以及地理信息系统(Geographical Information System,GIS)等关键组件的作用和功能。文章全面概述光纤通信在远程电力监控系统中的应用,强调光纤通信技术对于提高电力系统运行效率和可靠性的重要性。
