An experimental study of acoustic vibration effects in opticalfiber current sensors

This paper presents experimental results comparing the susceptibility of two different optical fiber current sensors to environmental acoustic vibrations. Of the two sensors that are tested, one employs a uni-directional current detection scheme, and the other a bi-directional in-line Sagnac interferometer. Acoustic vibrations are applied to various optical components of the two different types of current sensors     

基于电子剪切散斑干涉技术的光学电流互感器

基于Faraday磁光效应的光学电流互感器的研制和试运行表明,光学电流互感器的应用能产生一定的经济效益和社会效益.作为对其应用范围的补充,提出基于电子剪切散斑干涉方法的光学电流互感器,并设计相应的磁场力敏感传感器,其原理是待测电流的磁场力作用于传感器使之变形,用电荷耦合器件记录传感器的变形图像,对图像进行处理得到待测电流的磁场力或电流大小.实验室的可重复性和抗干扰性实验表明,所设计的光学电流互感器可用于现场使用.     

Sagnac式光纤电流互感器的光波偏振特性建模及误差特性分析

Sagnac式光纤电流互感器要求光波具有特定的偏振特性。起偏器、波片、保偏光纤主轴熔接等因素均会引起光波偏振误差,非理想的偏振光波导致互感器干涉信号串扰。围绕Sagnac式光纤电流互感器偏振误差特性,采用琼斯矩阵建立光纤电流互感器光波偏振模型,分析光纤电流互感器中线偏振态及圆偏振态演变过程;以光纤电流互感器光波偏振模型为基础,研究光波偏振器消光比、保偏光纤主轴熔接角以及波片相位延迟角对光纤电流互感器光波偏振及性能的影响。     

Highly Accurate Fiber-Optic DC Current Sensor for the Electrowinning Industry

A fiber-optic current sensor for direct currents up to 500 kA is presented. Applications include current measurement for process control and protection in the electrowinning industry, for example at aluminum smelters. The sensor offers significant advantages with regard to performance and ease of installation compared to state-of-the-art Hall-effect-based current transducers. The sensor exploits the Faraday effect in an optical fiber and measures the path integral of the magnetic field along a closed loop around the current-carrying bus bars. The differential magnetooptic phase shift of left and right circular light waves propagating in the fiber is detected by means of a novel polarization-rotated reflection interferometer. Fiber gyroscope technology is employed for signal detection and processing. The fiber is packaged in a flexible strip of fiber reinforced epoxy, which can be installed without opening the current-carrying bus bars. Subsequent recalibration is not necessary. The sensor achieves accuracy within plusmn0.1% over a wide range of currents and temperatures     

输电线路光差动保护初探

全光纤电流互感器是通过Faraday磁光效应测量载流导体中电流,不存在磁饱和、测量范围广、线性度好。由于载流导体中电流磁场效应可以叠加,可将输电线路差动电流测量转换为利用光学器件在光路层面直接进行Faraday磁光效应偏转角的运算,不需要繁复的对时就可直接获得线路两端电流差值,在此基础上构成光差动保护。在PSCAD中搭建光差动保护模型,仿真结果表明光差动保护测量差流能够反映实际差流变化情况,采用固定门槛值的光差动保护对区内故障具有较高的灵敏度,在区外故障时具有一定的可靠性。     

光纤振动传感器的信号检测电路设计

基于干涉仪的相位调制型光纤传感器具有极高的灵敏度,其中探测微弱光信号的光电信号检测电路起着重要的作用。针对光纤振动传感器系统,分析了PIN光电二极管前放电路和典型跨阻抗PIN-FET的组件电路,为减小前放I/V变换电路中跨阻阻值很大而带来的热噪声,设计了T型电阻网络。利用结构简单、性价比高的PIN光电二极管的前放检测和滤波器电路,对Sagnac干涉仪的输出的光信号进行了检测。实验表明该电路有效地降低了输出光电流噪声的均方值,其性能可靠,完全满足振动传感器的实际应用的测量要求。     

Development of a new type of optical transducer for measuring faultcurrent

An optical current transducer has been developed capable of measuring current up to short-circuit currents of 50 kA. The optical current transducer is composed of a current measuring unit, an insulator with integral optical fibers, and an optical interface. The current measuring unit combines a winding with a magnetic iron core and a solenoid coil containing a Faraday sensor. The optical interface converts optical signals into electrical signals. Prototype optical current transducers have satisfied target performance requirements and have demonstrated the ability to maintain that level of performance in field applications     

电力系统中光电电流互感器研究

电力系统中光电电流测量技术是国内外研究的热点和难点,光电电流互感器是未来电力工业电流测量发展的趋势。文中基于传统的电流互感器,利用数字调制和光功率推动技术,对有源光电电流互感器进行了研究;基于法拉第效应,利用相位补偿和传感头组装技术,研制了块状玻璃式无源光电电流互感器,同时还讨论了几种光电电流互感器的发展状况。     

一种新型光电式一体化电流电压互感器

介绍了一种将光学电流互感器和光学电压互感器同放于一个绝缘体内,可同时测量电流和电压的光电式一体化电流电压互感器。电流互感器采用法拉第镜式光学电流传感技术,电压互感器采用全反射光学电压传感技术,采用双光路补偿技术解决光强衰弱以及干扰双折射引起的误差。装置在佳木斯110 kV佳西变电站糖厂线试运行,运行情况良好,满足现场实际要求。     

基于小波分析和神经网络的光学电流互感器误差补偿系统

介绍了基于法拉第磁光效应的光学电流互感器的基本原理及线性双折射对系统性能的影响,结合电磁式电流互感器的良好稳态性能和光学电流互感器的无饱和暂态性能,设计了一种基于小波分析和神经网络的光学电流互感器误差补偿系统.小波分析用于检测电力系统的故障时刻从而区分暂态和稳态,神经网络用于补偿光学电流互感器线性双折射效应.通过仿真实验证明:系统能够对光学电流互感器的线性双折射等误差因素进行补偿,提高了光学电流互感器的稳定性和测量结果的准确性.