关键词: 复小波, 电能质量, 希尔伯特变换, 去噪

Abstract: To overcome the problem that real wavelet can not extract the phase information and the extraction of high-frequency coefficients is not very satisfactory in power quality disturbance detection, an orthogonal compactly supported complex wavelet is proposed and applied in power quality disturbance detection. The new algorithm combines Hilbert transform with wavelets transform together, constructs a set of complex values filters, then analyzes the imaginary and real part respectively to extract the phase, amplitude and appropriate combination information. Simulation results show that using such new complex wavelets can extract phase information, thus can detect the mutation more accurately in the power quality disturbance. Comparing with real wavelet and other complex wavelet, the new algorithm can distinguish the type of disturbance and has higher SNR with the same threshold condition in denoising of power quality signal.

Key words: complex wavelets, power quality, Hilbert transform, denoising