摘要
针对小电流接地系统故障选线,采用Hilbert-Huang变换和Hausdorff距离获得暂态零序电流的时频矩阵相似度作为故障选线判据。首先采用Hilbert-Huang变换建立每条出线的暂态零序电流时频矩阵,再将该时频矩阵经奇异值分解后,采用加权Hausdorff距离算法计算每条出线的暂态零序电流时频矩阵之间的相似度,据此故障特征进行故障线路筛选。采用仿真软件对不同故障条件分别进行仿真,结果表明该方法不受配电网故障初相角、故障点位置和故障点的接地电阻等内外因素的干扰,具有准确性高、对噪声不敏感、数据窗短和对采样频率要求不高等优点。
For the fault line selection of small current grounding system,the time-frequency matrix similarity of transient zero-sequence current is obtained by Hilbert-Huang transform and Hausdorff distance as the fault line selection criterion.Firstly,the time-frequency matrix of transient zero-sequence current is established by Hilbert-Huang transform for each branch line of the distribution network,and then the time-frequency matrix is decomposed by singular value.Then the weighted Hausdorff distance algorithm is used to calculate the time-frequency matrix similarity of transient zero-sequence current for each branch line of the distribution network,which identifies the faulty line according to the fault characteristics.Different fault conditions of small current grounding system are simulated by the simulation software.The results show that the method is not disturbed by internal and external factors such as the initial phase angle of the fault in the distribution network,the location of the fault point and the grounding resistance of the fault point,and has the advantages of high accuracy,insensitivity to noise,short data window and low sampling frequency requirements.
作者
王芳
WANG Fang(Electric and New Energy Institute,China Three Gorges University,Yichang,Hubei 443002,China)
出处
《东北电力技术》
2021年第8期49-53,57,共6页
Northeast Electric Power Technology
