毕业论文___基于fmea的电力变压器风险评估.doc

基于FMEA的电力变压器风险评估 The Risk Assessment of Power Transfomer Based on FMEA 届 电气与电子工程 学院 专 业 电气工程及其自动化 学 号 学生姓名 指导教师 完成日期 2014 年 6 月 2 日 摘 要 随着我国经济的快速发展，对电力系统的安全与稳定运行提出了更高的要求。而电力变压器是电力系统中的核心设备，是电网中电能交换、传输的枢纽。它的运行可靠性直接决定电力系统的安全与稳定并且关系国民经济的发展以及人民的日常生活。用变压器状态维修来取代定期维修是一种检修发展趋势。在电力系统状态维修中电力变压器的风险评估非常重要，通过对电力变压器风险评估，确定合理的维修策略，能够有效避免或减少电力系统故障的发生。 本文在变压器故障模式与影响分析的基础上，提出了变压器的风险评估体系。本文采用三个评价指标故障严重度(S)、发生概率(O)、和可检测程度(D)来对变压器的风险进行评估，传统FMEA通过风险优先数RPN来确定故障的风险等级，但是此种方法有一定的缺陷，传统评估方法存在人为因素影响、不区分各指标相对重要度以及因风险优先级指数相同而无法评价等缺点，为了解决这些缺陷，使变压器的风险评估更为科学客观，本文提出对三个评价指标进行模糊化处理并确定三个评价指标权重系数。最后得到改进的变压器风险评估方法的一般步骤，并用实例说明风险评估过程。 关键词：电力变压器 FMEA 风险评估 模糊 Abstract With the rapid development of Chinese economic,higher requirements is put forward to the safe and stable operation of power system. Power transformer is the core equipment in power system, is the hub of power exchange and transmission grid.It working reliability directly determines the safety and stability of power system, in relation to the development of the national economy and peoples daily life.Use the transformer state maintenance to replace the regular maintenance is a kind of development trend. Risk assessment of power transformer is very improtant in the power system state maintenance . The reasonable maintenance strategy effectively reduce or avoid the happening of the electric power system fault were determined through risk assessment. In this paper, the risk assessment of power transformer based on failure mode and effects analysis (FMEA) is researched. Risk assessment system of this paper choose three evaluation index severity (S), occurance (O) and detectable (D) to assess the risk of transformer. Traditional FMEA to determine the risk level by RPN, however, the traditional assessment method are not objective enough cant meet the needs of practical problems.It do not distinguish the index relative importance and have the same RPN