Statistical Analysis of Abnormal Electric Power Grid Behavior

Pacific Northwest National Laboratory is developing a technique to analyze Phasor Measurement Unit data to identify typical patterns, atypical events, and precursors to a blackout or other undesirable event. The technique combines data-driven multivariate analyses and engineering-modeling. The method identifies atypical events, provides a plain English description of the event, and gives the capability to use drill-down graphics for detailed investigations. The tool can be applied to the entire grid, individual organizations (e.g., TVA, BPA), or specific substations (e.g., TVA_CUMB). The tool is envisioned for (1) event investigations, (2) overnight processing to generate a Morning Report that characterizes activity that has occurred during the previous 10-30 days, and (3) potentially near-real-time operation to support the grid operators. This paper presents the current status of the tool and illustrations of its application to real world PMU data collected in three 10-day periods in 2007.