Online Ambient Oscillation Mode Monitor
Wide Area Measurement Systems (WAMS) could provide enough information to estimate the electromechanical modes which characterize the dynamic properties of the power grid. With the measured ambient frequency data from Frequency Network (FNET), an Empirical Mode Decomposition (EMD) filter is used to detrend the ambient signal, an Auto-Regressing Moving-Average (ARMA) model is proposed to describe the data and Modified Yule-Walker (MYW) algorithm is used to estimate the AR parameters. Fig. 1 shows the system architecture and Fig.2 describes the online website presenting the estimated dominant frequency and damping ratio from one of the interconnections in North America power grid.
Fig.1 System architecture
Fig. 2 Online mode estimation result