A Novel Event Detection and Classification Scheme Using Wide-Area Frequency Measurements

Automated event detection and classification are vital to power system monitoring. This article proposes a novel event detection and classification scheme based on wide area frequency measurement system (WAFMS). Raw frequency measurements obtained from WAFMS are used as the only input to the event detection and classification algorithm (EDCA). Wavelet-based signal pre-processing is used to denoise the data. Afterward, the rate of change of frequency (ROCOF) is estimated from the frequency measurements using the Kalman filter (KF). In the same step, phase angle difference (PAD) across different stations is estimated using WAFMS. Thus, the overall algorithm uses three features such as frequency, ROCOF, and PAD to detect and classify events in the power system. In the first step, an event is detected based on standard deviation (SD) of estimated ROCOF and PAD. In the second step, four types of events are classified using wide area frequency measurements. The suggested algorithms have been validated with real WAFMS data from the Indian Power System, recent 9th August 2019 U.K. blackout data collected from the U.K. power system, and 20th July 2017 oscillation event data obtained from ISO New England (ISO-NE) power system. As a promising tool for power system monitoring, the suggested scheme requires less input measurement for decision making and is having a low computational complexity, which is suitable for practical application.