Prony's method as a tool for power system identification in Smart Grids

Abstract

This paper investigates the theory, intuition and performance of two known implementations of Prony's method. Such methods are useful for identifying the individual modes of a system without constructing a component-based model. In the Smart Grid, Prony Analysis has been widely used on post-disturbance ring-down measurements, which have been increasingly available with the extensive deployment of PMU's. Both methods decompose the signal into decaying sinusoidals, and estimate the frequency, damping, amplitude and phase of each modal component. The first method is based on the original Prony's method, whilst the second method is based on the thought that the system can be viewed as a digital synthesis problem where the system has the properties of an infinite impulse response filter. Both methods employ EMD-based pre-filtering. Additionally, a cluster based approach is proposed for circumventing the issue of determining model order, so that the true modes of the estimation can be distinguished from the trivial modes.