Undecimated Wavelet Packet Transform Based Visualization of Time-Varying Power Quality Disturbance

In this paper, a method is presented for visualization of time-varying power quality disturbances in electrical power distribution system using undecimated wavelet packet transform (UWPT). The proposed method decomposes the input signal in various frequency bands and provides clear visualization of fundamental and each harmonic components. The UWPT is a time-invariant transform, which can lead to better understanding of time-dependent power quality disturbances. Various type of stationary and time-varying waveforms have been used to show the effectiveness of the proposed scheme. The results confirm that the proposed technique based on UWPT efficiently decomposes the fundamental and harmonics component from the distorted signal, reflecting its suitability for power quality monitoring and analysis.