Functional sensitivity concept and its application to power system damping analysis

A new sensitivity concept, in which the sensitivity is calculated with respect to the change of a transfer function as an independent complex variable, is proposed and its application to power system damping analysis investigated. A general expression for calculating the sensitivity in terms of hybrid representation of dynamic systems and a formula to predict mode displacements due to changes in some of the feedback controller´s parameters are presented to facilitate the sensitivity analysis. The new concept is illustrated through a simple 2nd-order system and the analysis procedures demonstrated by using a simplified power system stabilizer application example. The approaches of applying the sensitivity concept to analyze power system damping are shown. The results of a 13-machine power system study are given