【作者】 严颖维；

【导师】 忻向军；

【作者基本信息】 北京邮电大学 ， 光学工程， 2012， 硕士

【摘要】 本文研究了全光纤电流互感器的结构,比较分析了非干涉型电流互感器、Sagnac型电流互感器以及普遍采用的反射式结构电流互感器的优缺点。通过建立反射式结构的完整理论模型,详细研究了线性双折射对全光纤电流互感器的影响,并比较分析了引入大量圆双折射方法、制造极低线性双折射光纤、退火处理传感光纤圈以及分离法拉第效应和线性双折射等普遍采用的消除线性双折射影响方法的原理以及各自在实用中的缺点和不可实现性。提出了一种能够消除传感光纤部分线性双折射影响的新型反射式全光纤电流互感器结构,并通过采用琼斯矩阵建立系统理论模型、分析新型结构的偏振态演化以及仿真分析三种方法验证新型结构对传感光纤部分线性双折射的抑制作用,结果表明：通过在传感光纤中部插入光纤偏振旋转器的方法可以将测量误差控制在10-3数量级,另外,新型结构测量灵敏度和系统稳定性也得到提高。本文同时仿真分析了插入光纤偏振旋转器的位置对线性双折射抑制效果的影响。本文还介绍了光纤四分之一波片的温度特性及其制作方法,介绍了光源、相位调制器等硬件设备,并简要介绍了信号的闭环检测方案,确定系统输出光信号的提取办法。本文提出的消除传感光纤部分线性双折射影响的方法对全光纤电流互感器的实用化研究具有一定的意义。更多还原

【Abstract】 This article studied the structure of All-Fiber Optic Current Transformer, compared and analyzed the advantages and disadvantages of several kinds of common Optical Current Transformer, non-interference structure, Sagnac-type structure and commonly used reflective structure. Through the establishment theoretical model of reflective structure, studied the affect of Linear Birefringence for all-optical current transformer in detail. And analyzed and compared some methods to reduce the effect of Linear Birefringence, include introducing a large number of circular birefringence、making very low linear birefringence optical fiber、specially processing sensing optical fiber loop and separating the Faraday effect and the linear birefringence and soon on. The results show that these methods can not fundamentally eliminate the effects of Linear Birefringence, but introduce some new problems. An improved in-line All Fiber Optic Current Transducer was proposed in this paper. By appropriately setting the Fiber Polarization Rotator(FPR), bending-induced linear birefringence of the forward light and backward light will cancel with each other. Theoretic and polarization analyzing、Simulation show that new scheme has a large improvement on such LB reduction. The measurement error of AFOCT will be reduced to 10-3.In addition, sensitivity and stability of the system has also been improved by the new structure. The locate deviation of FPR has affected the inhibitory of Linear Birefringence was analyzed by simulation.At the same time, this article also studied quarter wave plate temperature characteristics、production methods and Jones matrix, prepared lights phase modulators and other hardware devices. Described the closed-loop signal detection scheme and determined the method of approaching output optical signal.New method of eliminating the linear birefringence affect in new in-line All Fiber Optic Current Transducer has a certain significance of research.更多还原