1互感器光波偏振特性建模-电测与仪表.DOC

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 孙健1，王立辉2 江苏省电力公司电力科学研究院， 南京 211103； 2. 东南大学 仪器科学与工程学院， 南京210096） 摘要：光纤电流互感器起偏器、波片、等光波偏振误差，Sagnac式光纤电流互感器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，研究器、波片光纤电流互感器光波偏振性能的影响。 关键词：光纤电流互感器；偏振误差；非互易相位；偏振态 中图分类号：TM452, TP212 文献标识码：文章编号：1001-1390（201）-0000-00 Research on optic polarization model and error characteristics of Sagnac fiber optic current transformer Sun Jian1, Wang Lihui2 (1. Jiangsu Electrical Power Company Research Institute, Nanjing 211103, China. 2. School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China) Abstract: Optic polarization states of sensing light wave in Sagnac fiber optic current transformer are limited. However, several factors including polarizer, quarter-wave retarder, splice angular, and so on will induce optic polarization error, and non-ideal polarized light waves will cause the interference signal crosstalk in transformer. Focused on characteristics of optical polarization error in fiber optic current transformer, we build optical polarization error models by using Jones matrix, then, analyze the evolution process of linear optic polarization state and circular optic polarization state in Sagnac fiber optic current transformer. Based on models of polarization state in Sagnac fiber optic current transformer, we investigate the influence of several main error factors on optical polarization error characteristics and performance theoretically, including extinction ratio in polarizer, splice angular between quarter-wave retarder and polarization maintaining fiber, and phase delay in quarter-wave retarder. Keywords: fiber optic current transformer, polarization error, nonreciprocal phase shift, optic polarization state 0引言 光纤电流互感器是基于Faraday磁光效应的电流测量装置，通过借鉴光纤陀螺光电信号处理技术，采用高速信号处理单元及电光相位调制器构建数字闭环反馈系统，实时测量光波环路中由磁场Farady效应导致的非互易性相位信息，进而获取外部电流信息[]，光纤电流互感器具有测量范围宽、动态特性好等优点，克服了电磁式电流互感器所存在的磁滞饱和、波形畸变等弱点，满足现代电力系统对电流测量值可靠性的需求。 光纤电流互感器就其光路结构部分而言，又可以分为两大结构：一种是反