A novel approach for electromechanical mode estimation based on PMU

Abstract

The paper describes a new electromechanical mode estimation algorithm based on phasor measurement units (PMU) data obtained under ringdown conditions. The main feature of the algorithm is that oscillation parameters aren't directly estimated but equivalent dynamic power system model is identified as a whole. In addition, identified model is based on physical relations underlying electromechanical transient processes in power system. Proposed algorithm is more accurate compared to main algorithms which are used for solving this problem. Besides, the algorithm allows to identify not only frequency and damping of electromechanical modes but also mode shape (amplitude and phase of oscillations). The proposed algorithm along with existing methods is tested using simulated data from simple three-nodes power system model.