干涉型光纤超声传感是一种高灵敏度的局部放电检测方法,但其现场应用时可能受到环境中低频振动噪声的干扰,降低检测灵敏度。为此,提出了相位跟踪反馈方法,确定了反馈系统参数;然后建立了真型126k V GIS局部放电超声传感研究平台,该平台...干涉型光纤超声传感是一种高灵敏度的局部放电检测方法,但其现场应用时可能受到环境中低频振动噪声的干扰,降低检测灵敏度。为此,提出了相位跟踪反馈方法,确定了反馈系统参数;然后建立了真型126k V GIS局部放电超声传感研究平台,该平台可模拟现场GIS电动力及开关动作所产生的振动噪声;最后,开展了GIS局部放电检测试验。研究结果表明:相位跟踪反馈可以补偿干涉传感系统中的相位变化,保证了传感系统灵敏度的稳定性;相位跟踪反馈方法可有效抑制由1.8 kHz以下低频噪声引发的相位衰落问题;采用相位跟踪反馈方法后,干涉型光纤超声局部放电传感系统测量灵敏度优于传统压电陶瓷传感系统,满足现场应用需求。展开更多
As one of the recent advances of optics and photonics,plasmonics has enabled unprecedented optical designs.Having a vectorial configuration of surface plasmon field,metallic nanostructures offer efficient solutions in...As one of the recent advances of optics and photonics,plasmonics has enabled unprecedented optical designs.Having a vectorial configuration of surface plasmon field,metallic nanostructures offer efficient solutions in polarization control with a very limited sample thickness.Many compact polarization devices have been realized using such metallic nanostructures.However,in most of these devices,the functions were usually simple and limited to a few polarization states.Here,we demonstrated a plasmonic polarization generator that can reconfigure an input polarization to all types of polarization states simultaneously.The plasmonic polarization generator is based on the interference of the in-plane(longitudinal)field of the surface plasmons that gives rise to versatile near-field polarization states on a metal surface,which have seldom been considered in previous studies.With a well-designed nanohole array,the in-plane field of SPPs with proper polarization states and phases can be selectively scattered out to the desired light beams.A manifestation of eight focusing beams with well-routed polarizations was experimentally demonstrated.Our design offers a new route to achieve the full control of optical polarizations and possibly advance the development in photonic information processing.展开更多
文摘干涉型光纤超声传感是一种高灵敏度的局部放电检测方法,但其现场应用时可能受到环境中低频振动噪声的干扰,降低检测灵敏度。为此,提出了相位跟踪反馈方法,确定了反馈系统参数;然后建立了真型126k V GIS局部放电超声传感研究平台,该平台可模拟现场GIS电动力及开关动作所产生的振动噪声;最后,开展了GIS局部放电检测试验。研究结果表明:相位跟踪反馈可以补偿干涉传感系统中的相位变化,保证了传感系统灵敏度的稳定性;相位跟踪反馈方法可有效抑制由1.8 kHz以下低频噪声引发的相位衰落问题;采用相位跟踪反馈方法后,干涉型光纤超声局部放电传感系统测量灵敏度优于传统压电陶瓷传感系统,满足现场应用需求。
基金This work was supported by the National Key Projects for Basic Researches of China(No.2012CB921501)and the National Natural Science Foundation of China(Nos.11174136,11322439,11321063,and 91321312)This work was also supported by the Dengfeng Project B and Outstanding Ph.D.candidate Program A of Nanjing University and the PAPD project of Jiangsu Higher Education Institutions.
文摘As one of the recent advances of optics and photonics,plasmonics has enabled unprecedented optical designs.Having a vectorial configuration of surface plasmon field,metallic nanostructures offer efficient solutions in polarization control with a very limited sample thickness.Many compact polarization devices have been realized using such metallic nanostructures.However,in most of these devices,the functions were usually simple and limited to a few polarization states.Here,we demonstrated a plasmonic polarization generator that can reconfigure an input polarization to all types of polarization states simultaneously.The plasmonic polarization generator is based on the interference of the in-plane(longitudinal)field of the surface plasmons that gives rise to versatile near-field polarization states on a metal surface,which have seldom been considered in previous studies.With a well-designed nanohole array,the in-plane field of SPPs with proper polarization states and phases can be selectively scattered out to the desired light beams.A manifestation of eight focusing beams with well-routed polarizations was experimentally demonstrated.Our design offers a new route to achieve the full control of optical polarizations and possibly advance the development in photonic information processing.
