【作者】 马静；

【导师】 王昌明；

【作者基本信息】 西安电子科技大学 ， 系统工程， 2014， 硕士

【摘要】 现代社会中各行各业对电能的依赖越来越大,潜在的电缆故障隐患随时可能对社会和国家造成严重的危害。因此,如何在故障发生后高效快速、精确地找到故障原因与位置并及时修复电缆故障,是一个亟待解决的难题。本论文开展对电力电缆的故障精确定位技术的研究,提出基于极化敏感阵列的电缆故障精确定位技术。论文通过查阅大量文献资料阐述了电力电缆产生故障的原因与故障的种类,针对不同的故障类型,制定故障检测的大致步骤流程:确定电缆出现故障相位、对电缆故障点位置进行粗测预定位和精确定位。首先分析现行精确定位方法存在的问题,在结合此方法的基础上引入基于极化敏感阵列的精确定位方法。然后针对故障精确定位过程中由高能冲击信号发生器对故障点进行有效冲击放电,产生出的电磁信号展开讨论。给出了基于极化敏感阵列情况下的进行参数估计方法,利用空间按一定几何结构分布的偶极子组或磁环组估计故障源所产生的电磁矢量信号的全部电场分量和磁场分量。结合电缆故障放电信号的数学模型与极化敏感阵列的阵列流形,分析和改进传统DOA估计算法,实现了近场故障点方位信息和位置距离信息的精确估计。利用经典改进ESPRIT算法估计近场源,通过增加一个COLD二维矢量天线(Co-centered Orthogonal Loop and Dipole),有效的解决了因为近场源效应而引起的角度近似问题。最后,通过计算机MATLAB验证仿真,从理论上论证了该算法的有效性。结合MATLAB仿真获得的数据进行分析,可以得到DOA对故障源估计的参数信息,通过方位角度和距离信息确定电缆故障的精确位置。仿真结果表明基于极化敏感阵列的电力电缆精确定位技术可以快速高效地实现高阻故障定位,与传统的电缆故障精确定位技术相比较具有显著的优势,在很大程度上解决了现行精确定位方法存在的问题,实现了故障精确定位的智能化。更多还原

【Abstract】 In modern society all walks of life increasingly rely on electricity,potential cable fault problem may have a great influence on the power system’s safety and people’s normal life, then have brought an inestimable economy loss for society at any time. So, how to prevent the power cable fault and repair the cable quickly is a problem starving for solution. As for this problem, this paper proposes an power cable fable precise location technology based on polarization sensitive array referring to the current development situation.Firstly, this paper introduces power cable fault and the categories of fault theoretically, then explains the fault detection flow: confirming fault phase、fault detection、pre location and fault pinpointing based on the category of fault. Then analyzing the problems of the existed accurate location methods, the paper proposes the accurate location based on polarization sensitive array combined with the existed methods. Then according to the process of fault accurate location, using high energy surge signal generator to make the fault effectively impulse discharge in order to produce electromagnetic signals that wo need to be discussed. At last,this paper introduce a new parameter estimation method based on improved Electromagnetic Vector Sensor, this sensor use spatially geometric structure distribution of short dipoles and magnetic loops to measuring all six electromagnetic field components of the incident wave field. This paper improves the traditional DOA estimation algorithm combined with polarization sensitive array and mathematic model of cable fault detection acquiring the precise estimation results of fault’s azimuth angle and distance information. The improved algorithm can estimate near field and solve the problem of angle approximation caused by near field effect availably through adding a COLD two-dimension vector antenna. Finally,the MATLAB simulation proves that this algorithm is available theoretically.Combined with the data produced in the MATLAB simulation, the fault estimation parameters based on DOA are acquired and the exact location of cable fault is found. The results indicate that this cable fault accurate location technology based on polarization sensitive array can quickly and effectively achieve fault location. Compared with traditional cable fault pinpoint location technology, this method exist obvious advantages and realize intelligent pinpoint cable fault in great degree.更多还原