引用本文: | 陈欢,何怡刚,肖建平,等.基于CWT和DWT相结合的谐波检测[J].电力系统保护与控制,2015,43(20):71-75.[点击复制] |
CHEN Huan,HE Yigang,XIAO Jianping,et al.Harmonics detection based on a combination of continuous wavelet transform anddiscrete wavelet transform[J].Power System Protection and Control,2015,43(20):71-75[点击复制] |
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摘要: |
提出了一种基于连续小波变换(CWT)和离散小波变换(DWT)相结合的电力系统谐波检测方法。首先利用CWT系数的幅值来检测谐波频率,该过程不用事先根据谐波次数确定分解层数,而只是确定尺度范围及步长,即可得出各次谐波频率。然后根据确定的谐波成分利用DWT来检测谐波幅值,并通过Matlab软件进行了仿真分析。仿真结果表明该方法有效地解决了基于离散小波变换的谐波检测方法中谐波次数未知而无法确定分解层数的难题,并能精确可靠检测各次谐波频率和相应的幅值。因此,CWT和DWT相结合是一种有效的电力系统谐波检测方法。 |
关键词: 谐波检测 小波变换 连续小波变换 离散小波变换 |
DOI:10.7667/j.issn.1674-3415.2015.20.011 |
投稿时间:2015-01-16修订日期:2015-03-09 |
基金项目:国家杰出青年科学基金(50925727);国防科技计划项目(C1120110004、9140A27020211DZ5102);教育部科学技术研究重大项目(313018);安徽省科技计划重点项目(1301022036) |
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Harmonics detection based on a combination of continuous wavelet transform anddiscrete wavelet transform |
CHEN Huan,HE Yigang,XIAO Jianping,LIU Maoxu,WANG Donglou |
(School of Electrical Engineering and Automation, Hefei University of Technology, Hefei 230009, China) |
Abstract: |
A harmonic detection method based on a combination of continuous wavelet transform and discrete wavelet transform is proposed. Firstly, harmonic frequencies are detected by the magnitude of CWT coefficients with a determined scale range and step size, while need not determine the harmonic decomposition level according to the harmonic numbers in advance. And then the DWT method is used to detect harmonic amplitude according to identified harmonic components. Simulation results are completed by Matlab, which show the proposed method can solve the problem that a undetermined decomposition level according to unknown harmonic numbers effectively and can detect the harmonic frequencies and the corresponding amplitudes accurately and reliably. Therefore, this proposed method is a valid method to harmonic detection in power system. |
Key words: harmonic detection wavelet transform continuous wavelet transform (CWT) discrete wavelet transform (DWT) |