一种基于特征根的配电网单端故障测距的新方法

发布时间：2018-01-30 19:28

本文关键词： 单相接地暂态特征特征频段拉氏变换特征根单端测距　出处：《电网技术》2014年03期 　论文类型：期刊论文

【摘要】：在零序电压、电流中,暂态分量的衰减时间常数及频率与故障距离相关,其值可由象函数特征方程的根表示。分析了该函数与故障距离的关系,提出了一种基于特征根的单端测距方法。该方法结合拉氏变换与双曲函数线路模型,由零序电压、电流象函数的特征方程,得到了象函数测距方程,同时,利用特征频段(SFB)的性质,提出了该测距方程在SFB内的等效形式,通过Prony算法,从采样信息中提取SFB内的特征根,采用搜索法求解超越方程,实现了故障测距。该单端测距方法可准确得到故障距离的解析表达式,且克服了传统双曲函数模型不能用于暂态计算的问题。大量的EMTP仿真实验结果验证了该方法的正确性,不受过渡电阻、故障初始角、中性点运行方式的影响,能够满足实际工程需求。
[Abstract]:In zero-sequence voltage and current, the attenuation time constant and frequency of transient component are related to the fault distance, which can be expressed by the root of the characteristic equation of the image function. The relationship between the function and the fault distance is analyzed. In this paper, a method of single end ranging based on characteristic root is proposed, which combines Laplace transform with hyperbolic function circuit model, from the characteristic equation of zero-sequence voltage and current image function, the image function ranging equation is obtained, at the same time. In this paper, the equivalent form of the range equation in SFB is put forward by using the property of characteristic frequency band SFB. The characteristic root in SFB is extracted from the sampling information by Prony algorithm. The fault location is realized by solving transcendental equation by searching method, and the analytical expression of fault distance can be obtained accurately by this method. And overcome the traditional hyperbolic function model can not be used in transient calculation. A large number of EMTP simulation results verify the correctness of the method, no transition resistance, fault initial angle. The impact of neutral operation mode can meet the actual engineering needs.
【作者单位】：输配电装备及系统安全与新技术国家重点实验室(重庆大学);
【分类号】：TM762.25
【正文快照】： 0引言配网电缆的故障多为单相接地故障,其故障测距一直是研究的热点和难点[1-2]。现有的方法主要有注入信号法、行波法[3-7]和故障分析法[8-18]。注入信号法需外加信号源,对电网会带来一定的影响,且不能判别瞬时性故障;行波法主要用于高压输电线路,受配网结构复杂、线路较短等

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