Phase angle‐based power system inter‐area oscillation detection and modal analysis

Abstract

AbstractElectromechanical oscillations associated with power system stability problems have been a primary concern of system planning, operation and control for decades. With growing loads, the need for long distance power exchange between power companies leads to the frequent occurrence of instability phenomena including oscillations. The growth of synchrophasor measurement‐based Wide‐Area Monitoring System (WAMS) technology in recent years provides the platform for real‐time system dynamic monitoring and analysis which has never before been realised. The North American Frequency Monitoring Network (FNET), as the only WAMS that covers the entire North American power grid, has the capability to realise accurate, high density, continuous monitoring of large interconnected power system dynamics. This paper presents an automatic power system oscillation detection method based on FNET phase angle measurements. In addition, dynamic characteristics obtained from modal analysis of 28 FNET event cases are also introduced. The technique used for modal decomposition and reconstruction is called the Matrix Pencil method, which comes from the pencil‐of‐function approach. This is a very computationally efficient and noise robust signal processing method for dynamic information extraction. Inter‐area oscillations, which are associated with groups of generators, are the only concern in this paper. Copyright © 2010 John Wiley & Sons, Ltd.