基于变分模态分解与近似熵的输电线路两相接地故障诊断  

Two-phase Grounding Fault Diagnosis of Transmission Lines Based on Variational Mode Decomposition and Approximate Entropy

作　　者：李振璧[1] 张坤 姜媛媛[1] 王康[1] 程浩[1] 

机构地区：[1]安徽理工大学电气与信息工程学院,淮南232001

出　　处：《科学技术与工程》2018年第5期70-75,共6页Science Technology and Engineering

基　　金：安徽理工大学研究生创新基金(2017CX2033);安徽省高校优秀青年人才支持计划重点项目(gxyq ZD2016082);国家自然科学基金(51604011);安徽省自然科学基金(1708085QF135)资助

摘　　要：针对现有电力系统输电线路故障信号分析方法中,存在故障信号特征遗失等问题,提出一种基于变分模态分解(VMD)-近似熵(Ap En)的两相接地故障诊断新方法。首先选取故障点处容易获取的相电压信号作为故障信号;然后对各相故障信号进行VMD分解得到其分量,进一步提取各相IMF分量的近似熵值并作为一个特征向量。通过分析各相特征向量的模值,最终诊断出输电线路两相接地故障所在相。选取IEEE 5节点标准测试系统验证;并与EMD-Ap En算法进行比较。实验结果表明,提出的VMD-Ap En方法准确可靠,避免了EMD分解时产生模态混叠的现象;更能有效地诊断出输电线路两相接地故障所在相,具有较好的实用性。A new fault diagnosis method based on VMD-Ap En was proposed to solve the problem of failure signal feature loss in the fault signal analysis method of transmission line fault of existing power system. Firstly,the phase voltage signal easily obtained at the fault point is taken as the fault signal. Then,the IMF component was decomposed by VMD,and the approximate entropy of the IMF component was extracted and taken as an eigenvector.By analyzing the modulus of the eigenvector of each phase,the phase of the two-phase ground fault of the transmission line was diagnosed. The IEEE 5-node standard test system was validated and compared with the EMD-Ap En algorithm. The experimental results show that the VMD-Ap En method proposed is accurate and reliable,which avoids the phenomenon of modal aliasing when EMD was decomposed,and can effectively diagnose the phase of the two-phase ground fault of the transmission line,and has good practicability.

关 键 词：输电线路 故障诊断 变分模态分解 近似熵 两相接地故障 

分 类 号：TM711[电气工程—电力系统及自动化]