Identification of electromechanical oscillatory modes based on variational mode decomposition

This paper introduces Variational Mode Decomposition (VMD) to identify electromechanical oscillatory modes in power systems. The identification process is based on the time-frequency analysis of nonlinear signals which arise after a large disturbance. VMD provides signal decomposition to convert the oscillatory power signal into mono-component signals or modes. This analysis is accomplished by an optimal and recursive statement in time frequency, yielding the modes and reconstructed signal estimates, and providing information on their instantaneous modal characteristics such as amplitude, frequency, damping and energy, via Hilbert transform. The results demonstrate the applicability of the proposition in both theoretical and a real wide-area monitoring system.