电力系统谐波源及谐波检测方法研究

近年来,谐波污染已成为影响电力系统安全稳定运行的重要因素之一。文章在总结谐波检测方法的研究基础上,首先对整流性负荷和冲击性负荷两种谐波源的谐波产生机理进行了简要分析,阐明电力系统中主要存在的谐波成分;再介绍目前常用的FFT变换和小波变换两种谐波检测方法;最后,通过Matlab仿真软件对模拟构建的谐波模型和变电站实测数据进行分析,并对比了两种检测方法的优势和不足。分析证明,傅里叶分析是能够准确地反映信号幅值和相位的频域特征,而小波变换能直观地显示基波和各次谐波在时域和频域的波形信息。在实际的工程应用中需要选择适当的算法,结合各种谐波检测方法的优势,以便得到快速准确的结果。

Research of Power System Harmonic Source and Harmonic Detection Method

In recent years, the harmonic pollution is an important factor to impact on safe and stable operation of the power system. This paper summarizes the harmonic detection methods based on the study. First, In order to clarify the main harmonic components of power system, harmonic generation mechanism of the rectifier load and impact load is briefly analyzed. Then, the harmonic detection methods of FFT and wavelet transform which are the most commonly used have been introduced. Finally, the harmonic model and the measured data of the substation have been analyzed by Matlab simulation software, and compared the strengths and weaknesses of two methods. Analysis shows that the Fourier analysis have the ability to accurately reflect the signal amplitude and phase characteristics in the frequency domain, and the wavelet transform can visually display the waveform information of fundamental and harmonics in the time domain and frequency domain. In practical engineering applications, in order to get fast and accurate results, it is necessary to select the appropriate algorithm, which combined with the advantages of various harmonic detection methods.