This research monograph is in some sense a sequel to the author's earlier one (Power System Stability, North Holland, New York 1981) which devoted cons- erable attention to Lyapunov stability theory, construction of Lyapunov fu- tions and vector Lyapunov functions as applied to power systems. This field of research has rapidly grown since 1981 and the more general concept of energy funct ion has found wide spread application in power systems. There have been advances in five distinct areas (i) Developing energy functions for structure preserving models which can incorporate non-linear load models (ii) Energy fu- tions to include detailed model of the generating unit i. e. , the synchronous machine and the excitation system (iii) Reduced order energy functions for large scale power systems, the simplest being the single machine infinite bus system (iv) Characterization of the stability boundary of the post-fault stable eQui- brium point (v) Applications for large power networks as a tool for dynamic security assessment. It was therefore felt appropriate to capture the essential features of these advances and put them in a somewhat cohesive framework. The chapters in the book rough ly fo llow this sequence. It is interesting to note how different research groups come to the same conclusion via different reas- ings.

This research monograph is in some sense a sequel to the author's earlier one (Power System Stability, North Holland, New York 1981) which devoted cons- erable attention to Lyapunov stability theory, construction of Lyapunov fu- tions and vector Lyapunov functions as applied to power systems. This field of research has rapidly grown since 1981 and the more general concept of energy funct ion has found wide spread application in power systems. There have been advances in five distinct areas (i) Developing energy functions for structure preserving models which can incorporate non-linear load models (ii) Energy fu- tions to include detailed model of the generating unit i. e. , the synchronous machine and the excitation system (iii) Reduced order energy functions for large scale power systems, the simplest being the single machine infinite bus system (iv) Characterization of the stability boundary of the post-fault stable eQui- brium point (v) Applications for large power networks as a tool for dynamic security assessment. It was therefore felt appropriate to capture the essential features of these advances and put them in a somewhat cohesive framework. The chapters in the book rough ly fo llow this sequence. It is interesting to note how different research groups come to the same conclusion via different reas- ings.

SMALL SIGNAL ANALYSIS OF INTEGRATED POWER SYSTEMS is an essential tool to discover possible low frequency oscillations which if undamped may lead to major power failures. This book covers various aspects of this phenomenon from modeling to techniques to control them. The book covers low frequency in the 1-3 Hz range as well as sub synchronous oscillations in the 10-50Hz range. Damping techniques for both types of oscillations are discussed as well as design of Power System stabilizers. Modeling and design of FACTS devices in included. Selective computation of Eigenvalue(s) in a large system is discussed. Wind power systems and its integration into the existing grid is discussed along with small signal analysis.

Power system oscillations without a big disturbance occur spontaneously in a power system and if they are not damped out properly may lead to grid failure. In this book we examine the methodology to study this phenomenon from several angles. Modeling the system to investigate these oscillations is given top priority along with physical interpretation of the phenomenon. The book covers low frequency 1-3 Hz as well as sub synchronous oscillations in the 10-50 Hz range. The latter are called torsional oscillations. Design of Power system stabilizers as well as damping techniques for sub synchronous oscillations are discussed. Modeling and design of FACTS devices is included. The small signal analysis of multimachine systems along with the selective computation of Eigen value(s) of interest in a large system is presented.