Wavelet-Based Disturbance Analysis for Power System Wide-Area Monitoring

This paper proposes a wavelet-based method to obtain the characteristics of frequency and voltage derivatives for disturbance analysis. Frequency and voltage derivatives are important indicators to reflect the degree of disturbances and manifest power system dynamics. However, current computational methods for the indicators have noticeable drawbacks with respect to the accuracy. Wavelet transform-based multiresolution analysis (WT-based MRA) is introduced to obtain the characteristics of the indicators by computed maximum wavelet coefficients (WCs). Results from numerical experiments show a superior performance of WT-based MRA over the existing methods. Generation loss and load change as two major types of disturbances are studied to verify the proposed method. The disturbances are simulated in PSS/E for IEEE New England 39-bus system. The relationship of maximum WCs and power variation is discussed. Maximum WCs can provide enough information to distinguish the location of generation loss and estimate the load power variation.