A statistics-based threshold for the RMS-energy oscillation detector. (June 2021)

• Record Type: Journal Article
• Authors: Follum, Jim; Holzer, Jesse; Etingov, Pavel
• Is Part Of: International journal of electrical power & energy systems. Volume 128(2021)
• Publication Date: 2021-06
• Subjects: Forced oscillation -- Electromechanical oscillation -- Synchrophasor measurement -- Phasor measurement unit -- Wide-area situational awareness -- Statistical detection theory; Electrical engineering -- Periodicals; Electric power systems -- Periodicals; Électrotechnique -- Périodiques; Réseaux électriques (Énergie) -- Périodiques; Electric power systems; Electrical engineering; Periodicals; 621.3
• DOI: 10.1016/j.ijepes.2020.106685
• Languages: English
• ISSNs: 0142-0615

Abstract

Highlights: Power system operators rely on oscillation detection to maintain grid reliability. A theoretical expression for the threshold of an accepted oscillation detector is formulated. The expression simplifies the process of setting thresholds. Compatible thresholds support coordination among system operators. Abstract: Power system operators and reliability coordinators currently rely on extensive baselining studies to set thresholds for their oscillation detectors. The resulting thresholds are based largely on engineering judgment and may vary significantly between organizations. In this paper, statistical distribution theory is used to derive a threshold for the widely deployed root-mean-square (RMS)-energy oscillation detector. This expression provides a theoretical basis for the detector's configuration, simplifies the process of selecting the threshold, and enables improved consistency among organizations that need to coordinate during system-wide oscillations. Three methods for calculating the threshold using synchrophasor measurements are also proposed. These methods ensure that the threshold can be calculated reliably for various applications. Tests with simulated and field-measured data demonstrate that the statistics-based threshold provides consistent detection of oscillations while maintaining a low probability of false alarm.