Visualization of interarea oscillations using an extended subspace identification technique

Online assessment and control of low-damping power system oscillations is a challenging problem. This paper discusses the use of subspace stochastic method to visualize and characterize the time evolution of power system electromechanical modes. Using normalized instantaneous amplitudes of modal components, two time-varying indexes to determine mode distribution maps are proposed and tested. The method is well suited to automation and can be incorporated to existing wide-area monitoring systems. Simulation studies on a 16-machine, 68-bus test system show the applicability of the proposed technique. © 2013 IEEE