毕业论文(范文).doc

毕业设计论文 基于EMTP的输电线路故障测距仿真研究 学生姓名： 陆川 班级学号： 电力061 206060223 院、系、部： 电力工程学院 专 业：电气工程及其自动化（电力系统及其自动化） 指导教师： 陈凡 讲师 2010年06月 南 京  Undergraduate Design(Thesis) INVESTIGATION OF TRANSMISSION LINE FOR FAULT LOCATION BASED ON EMTP SIMULATION BY LU Chuan Supervised by Lecture CHEN Fan School of Electric Power Engineering Nanjing Institute of Technology June 2010  摘要 高压架空线路的准确故障测距是从技术上保证电网安全、稳定和经济运行的重要举措之一，具有巨大的社会和经济效益。长期以来，高压输电线路的准确故障测距受到电网运行和管理部门以及专家学者的广泛重视。 本文在继承前人大量研究成果的基础上，首先，比较全面的对已有的故障测距方法进行了概述，分析现有的故障测距方法的主要优缺点。其次，基于行波的输电线路双端测距算法只用到了到达故障线路两侧母线的第一个故障初始行波波头，其可靠性高；但行波波速对其定位精度存在一定的影响；实际的波速受到线路参数频变及地理位置、气候等诸多因素的影响；本文介绍了一种双端行波故障测距新方法，该方法利用故障初始行波和反射行波到达线路两端的时刻来进行故障定位，有效降低了行波波速的不确定和输电线路长度差异对定位结果的不利影响，提高了定位精度。接着，利用EMTP进行了仿真计算，仿真结果证明了其准确性。最后，对输电线路故障测距的研究与应用前景进行了展望。 关键词： 输电线路，行波，双端故障测距，波速 Abstract Accurate fault location will lighten the work of seeking for the fault and facilitate quicker repair and restoration to reduce the damages due to stop of power supply, once faults occur on the transmission line. To ensure proper operation of the system, it is of great importance to determine the exact fault location when fault happens. For many years, accurate fault location of high voltage transmission line has been paid much attention to. On the basis of a lot of predecessors’ achievement, at first, some existing methods of transmission line fault location are summarized and those methods’ primary merits and disadvantages are analyzed as well. At second, based on the travelling wave, double ended approach only deals with the first transient travelling wave reaching the two buses of the fault line. Although it has higher reliability, its location accuracy can also be affected by the wave speed which will be influenced by such factors as geographical position, climate, line parameter changes because of the freque