一种基于LCD-Hilbert变换和奇异谱熵的配电网暂时过电压类型识别方法  

Temporary overvoltage classification and recognition method of distribution network based on LCD-Hilbert transform and singular-spectrum entropy

作　　者：金涛[1] 许立彬 高伟[1] 郭谋发[1] 陈永往 JIN Tao;XU Li-bin;GAO Wei;GUO Mou-fa;CHEN Yong-wang(College of Electrical Engineering and Automation,Fuzhou University,Fuzhou 350116,China;State Grid Fujian Jinjiang County Electric Power Supply Co.,Ltd.,Quanzhou 362200,China)

机构地区：[1]福州大学电气工程与自动化学院,福州350116 [2]国网福建晋江市供电有限公司,福建泉州362200

出　　处：《电机与控制学报》2018年第11期26-36,共11页Electric Machines and Control

基　　金：国家自然科学基金(51677030);福建省自然科学基金(2016J01218);福建省教育厅中青年教师教育科研项目(JA15086)

摘　　要：针对当前电力系统配网领域的过电压识别问题,提出一种基于时频分布特征的配电网暂时过电压分类识别方法。在暂时过电压中,单相金属性接地过电压的三相电压能量分布均匀度最低,间歇性弧光接地零序电压的直流分量最高,铁磁谐振零序电压信号在幅值和频率集中频带上存在很大差异。计算零序电压能量贡献率、零序电压平均值和三相电压奇异谱熵,提取过电压信号的时域能量分布特征;采用局部特征尺度分解(LCD)和Hilbert变换结合带通滤波算法计算零序电压重心频带,提取过电压信号的频域能量分布特征;结合阈值判别法实现暂时过电压类型识别。该方法不需要分类器,算法简单,计算时间少。仿真和实验表明该识别方法在不同故障条件下均有更高的识别率。In view of the problem of overvoltage identification in the current distribution network of power system,a temporary overvoltage classification and recognition method of distribution network based on time-frequency distribution characteristics was proposed.In neutral isolated power system,the three-phase voltage of bolted single-phase ground overvoltage has the lowest energy distribution uniformity;the zero-sequence voltage of intermittent arc grounding overvoltage has the highest DC component;and the zero-sequence voltage of different kinds of temporary overvoltage has great differences on amplitude and frequency concentration band.The energy contribution rate of the zero-sequence voltage,the mean value of the zero-sequence voltage,and the singular spectrum entropy were calculated to extract the time-domain energy distribution features.Local characteristic-scale decomposition(LCD),Hilbert transform and the band-pass filter algorithm were adopted to calculate the center gravity frequency band,so as to extract the frequency-domain energy distribution features.Finally,the types of temporary overvoltage were recognized by the threshold discrimination method.The method does not need classifier,and it has the advantages of simple algorithm and little computation time.Under different fault conditions,higher recognition rate was obtained both in simulation and reality testing.

关 键 词：中性点不接地系统 暂时过电压 能量贡献率 平均值 奇异谱熵 重心频带 

分 类 号：TM73[电气工程—电力系统及自动化]