一种基于小波的电网谐波检测新方法  

New Method of Harmonic Detection Based on Wavelet

作　　者：王松[1,2] 石双双[2] 李德和[2] 陈超[3] 吴建华[2] 

机构地区：[1]北京交通大学电气工程学院,北京100044 [2]山东大学威海分校机电工程学院,威海264209 [3]海军装备研究院信息技术研究所,北京102200

出　　处：《系统仿真学报》2009年第3期814-817,共4页Journal of System Simulation

摘　　要：在电力系统中存在许多非线性负载,由此产生的谐波对电网的电能质量造成很大的影响。为了保证电网的电能质量,必须监测由此产生的谐波。首先讲解用于谐波检测的小波变换的理论,其次在MATLAB中用FFT、小波分解和小波包变换三种方法对由电焊机产生的谐波电流进行了仿真分析与计算。仿真结果表明:小波分解能够有效地分离基波,小波包变换能够分离任意次谐波.该方法具有普遍适用性,与使用昂贵的专用测量仪器相比,不失为一种好的替代方法。In power systems there are many non-linear loads, and the harmonics generated by the non-linear loads can cause great impact to the power system. Thus, it is important to monitor and analyze harmonics generated by these equipments in order to get a better power quality. The theoretical foundation of WT （wavelet transform） in harmonic measurement was introduced. The harmonic currents of welding machine using tools of FFT, WD （Wavelet Decomposition） and WPT （wavelet packet transform） in MATLAB were calculated and analyzed. Simulation results show that the method of WD can extract fundamental wave effectively, and the method of WPT can extract any times of harmonics. This method is of universal applicability, particularly compared with the expensive power analyzing equipments, which may be a good alternative.

关 键 词：谐波 MATLAB仿真 小波分解 小波包变换 

分 类 号：TP274.2[自动化与计算机技术—检测技术与自动化装置]