Locating the Source of Oscillation With Two-Tier Dynamic Mode Decomposition Integrating Early-Stage Energy

This paper presents an improved method to locate the sustained oscillation source using measurements, e.g., voltage measurements from phasor measurement units (PMUs). Based on dynamic mode decomposition (DMD), the proposed method exploits the spatiotemporal patterns of dominant dynamics from the measurements to detect the oscillation and identify the source. It significantly enhances the overall performance by incorporating the initial stats as input such that the state matrix represents the post-mortem dynamics. We also propose a two-tier structure to further improve the robustness and accuracy: full-time analysis over the entire time frame of interest to identify the problematic modes and candidate sources and peak-time analysis to identify the actual source. These analyses provide insights into the oscillatory energy distribution among the monitored buses at the early stage of the oscillation and normalized contribution factors pointing to the source robustly. Studies on the simulation data in WECC 179 and 240 bus systems and those on a real case in ISO-NE validate the effectiveness of the proposed method.