Analysis of electromechanical modes using multichannel Yule-Walker estimation of a multivariate autoregressive model

Stability of power systems can be analyzed by monitoring the electromechanical oscillatory modes. This paper investigates the use of multichannel Yule-Walker (YW) estimation of a multivariate autoregressive model (MAR) for the measurement based modal analysis of power systems. The proposed YW-MAR method utilizes data that are simultaneously measured through a wide area monitoring system (WAMS). The performance of the method is analyzed by applying it to data generated with the New England test system. The results indicate that the frequencies and the damping ratios of electromechanical oscillatory modes can be accurately analyzed by using the YW-MAR method and the method is not significantly affected by measurement noise or losing a measurement signal.