三相光学电流互感器是以 Faraday磁光效应为基础 ,以电力系统三相电流为测量对象的新型电力计量装置 ,它在电力系统计量和继电保护中具有广阔的应用前景和巨大的市场潜力 ,本文论述了三相光学电流互感器的基本原理 ,重点分析了系统中光耦合器性能改变对三相光学电流互感器的影响 ,为三相光学电流互感器的建立、系统中光耦合器的选择和数据处理方法提供理论指导 Three-phase optical current transformer is based on Faraday magneto-optic effect, taking power system three-phase current as measuring object, which has wide application prospect and great market potential in power system measurement and relay protection , This paper discusses the basic principle of three-phase optical current transformer, focusing on the analysis of the system optocoupler performance changes on the three-phase optical current transformer, the establishment of three-phase optical current transformer, the system optocouplers Selection and data processing methods provide theoretical guidance