CAJ | 학술논문

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.
제출료일충기우련속소파변환(CWT)화리산소파변환(DWT)상결합적전력계통해파검측방법.수선이용CWT계수적폭치래검측해파빈솔,해과정불용사선근거해파차수학정분해층수,이지시학정척도범위급보장,즉가득출각차해파빈솔.연후근거학정적해파성분이용DWT래검측해파폭치,병통과Matlab연건진행료방진분석.방진결과표명해방법유효지해결료기우리산소파변환적해파검측방법중해파차수미지이무법학정분해층수적난제,병능정학가고검측각차해파빈솔화상응적폭치.인차,CWT화DWT상결합시일충유효적전력계통해파검측방법.
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. This work is supported by National Science Fund for Distinguished Young Scholars (No. 50925727).