输电线路微机继电保护 本科毕业设计论文.doc

输电线路微机继电保护-本科毕业设计论文 本科毕业设计（论文） 输电线路微机继电保护 装置可靠性分析 学 院 专 业 电气工程及其自动化 年级班别 学 号 学生姓名 指导教师 年 月 日 摘 要 随着电力系统的发展、“西电东送”建设的加快，超高压、远距离、大容量输电及全国性联网的局势已成必然。继电保护装置在电力系统中发挥着重要作用，其正常工作与否将对电力系统的运行造成重大影响。因此如何提高继电保护装置的可靠性也就成为人们日益关注的重要课题。 本设计论文首先阐述了电力系统继电保护的可靠性,接着分析影响继电保护装置可靠性的各种因素.并主要对电力系统数字式保护的可靠性评估进行了探索.主要分如下两点: 1.分析二次系统软/硬件特点,提出二次设备和系统中的软/硬件可靠性模型和失效率预测方法. 2.结合数字保护的工作特点,应用保护系统马尔可夫模型和状态空间模型,求解保护拒动失效率,保护误动失效率,保护误动频率,保护拒动频率和保护可用度. 关键词:继电保护,可靠性,马尔可夫模型 Abstract Along with the development of the power system, transmitting electricity by exceed-high voltage, long distance, great capacitance and nationally electricity network will come true. The protector is quite important in power system, whether it can work normally or not will bring some grave infections. Therefore, we pay attention increasingly to how to improve the reliability of the protector. The paper first explains the dependability of relay protection in power system,then analyses various kinds of factors that may influence the dependability of the relay protector.Then the paper presents a reliability evaluation approach on digital protection.The main work is as follows: Firstly,the paper analyzes the characteristics of hardware and software in secondary system and presents method for predicting basic cell’s hardware and software failure rate in secondary system. Secondly, with the protection of digital features, application protection system Markov model and the state-space model, for the protection of refusing failure rate, the protection misoperation failure rate, the protection misoperation frequency, according to the protection of dynamic frequency and the degree of protection available. Key words：Power System Protection， Reliability，Markov model 目 录 1 绪论………………………………………………………………………………………….1 1.1研究的目的和意义………………………………………………………………………..1 1.2电力可靠性研究历史……………………………………….……………………………..2 1.3研究的背景……………………………………………………………………….………..3 1.3.1国外近年来发生的停电事故及影响………………………………..……………..3 1.3.2国内近年来发生的停电事故及影响…