Online Oscillation Alert
Low-frequency oscillation events significantly impact the stability of the power system. By utilizing the real time measurement data, either frequency or phasor angle, the low-frequency oscillations can be detected quickly because they have a specific signature. The online low-frequency oscillation alert application analyzes the real time frequency measurement provided by the FNET/GridEye system and accurately recognizes the oscillation events before the power system stability is compromised. Once an event is detected, the application sends alerts to the necessary clients and automatically stores the disturbance measurement data. Theoretically, the oscillation event displays typical signatures in both frequency and phasor angle measurements as shown in the following figure.
 T. Xia, Y. Zhang, L. Chen, Z. Yuan, P. N. Markham, Y. Ye, and Y. Liu, "Phase angle-based power system inter-area oscillation detection and modal analysis," European Transactions on Electrical Power, vol. 21, no. 4, pp. 1629-1639, May 2011.
 Z. Yuan, T. Xia, Y. Zhang, L. Chen, P. N. Markham, R. M. Gardner, and Y. Liu, "Inter-area oscillation analysis using wide area voltage angle measurements from FNET," in 2010 IEEE Power and Energy Society General Meeting, 2010, pp. 1-7.