Recent developments in modal estimation of power system electromechanical oscillations

This paper presents three data-driven methods to monitor electromechanical oscillations in power systems during ambient operation. The characteristics of the methods are compared and the differences in the characteristics are explained. The results indicate that all three methods are suitable for estimating the damping and frequency of electromechanical oscillations. The paper also studies the validity of the assumption that the load variations in power systems are Gaussian distributed. This is a common assumption in damping estimation methods. The assumption is shown to be valid for the studied loads.