由于通信网络设备缺乏实验数据与现场数据,无法用常规方法对其进行有效性分析,文章根据通信系统的特点,建立了电力通信系统电路的失效模型,讨论了电力通信系统电路有效性研究的方法,给出了用三角模糊数进行模糊故障树分析的方法和步骤,以及模糊重要度分析的方法——限位系数法,并用这一方法进行分析确定影响通信系统失效的主要因素,为电力通信系统电路有效性研究提供了技术途径。 Due to the lack of experimental data and field data, communication network equipment can not carry out validity analysis by conventional methods. According to the characteristics of communication system, this paper establishes the failure model of power communication system circuit and discusses the method of circuit effectiveness study of power communication system The methods and steps of fuzzy fault tree analysis using triangular fuzzy numbers and the method of fuzzy importance degree analysis - the limit factor method are given. The main factors affecting the failure of communication system are determined by this method. The research of system circuit effectiveness provides a technical approach.