基于小波变换的d-q电力谐波检测法研究

为了更有效地治理电力系统谐波污染,文中采用一种基于小波变换的d-q电力谐波检测法。该方法使用小波变换将基于瞬时无功功率理论d-q法的LPF滤波环节替换,并在Park变换后滤除负序分量。小波变换采用小波多分辨率分析实现,将小波变换后的直流分量和各次交流分量进行重构,分别得到三相电流的基波和各次谐波。在PSCAD/EMTDC中进行基于小波变换的d-q法建模和仿真实验,并通过与d-q法的仿真结果进行比较来验证该方法的可行性和精确度。结果表明该方法能够更精确的检测基波和各频段谐波分量。

Research of d-q Method Based on Wavelet-transform for Harmonic Analysis of Power System

Power quality is seriously affected by increasing-harmonic pollution in the power system. In order to manage the power system harmonic pollution more effectively, the paper a new develops instantaneous reactive power theory d-q method based on Wavelet-transform for harmonic analysis of power system. In the new approach, LPF for separating fundamental-wave of instantaneous reactive power theory d-q method will be replaced by the wavelet transform, and the link for eliminating the negative sequence component will be added after Park-transform. Wavelet transform is implemented by the wavelet multi-resolution analysis,fundamental wave and harmonic components of the three-phase current can be obtained by reconstructing the DC component and frequency AC component after Wavelet-transform. Modeling and simulation of this approach based on PSCAD, and the new d-q method is compared with d-q method. Experimental results show that d-q method based on Wavelet-transform can more accurately detect the fundamental and harmonic components.