The general concepts associated with applying power system stabilizers utilizing shaft speed, ac bus frequency, and electrical power inputs are developed in this first part of a three-part paper. This lays the foundation for discussion of the tuning concepts and practical aspects of stabilizer application in Parts II and III. The characteristics of the "plant" through which the power system stabilizer must operate are discussed and the implications upon stabilizer tuning and performance are noted. A general approach for analyzing stabilizers utilizing an arbitrary input signal is described and applied to the frequency and electrical power input signals.

Applying Power System Stabilizers Part I: General Concepts

An attempt is made in This work to present critical literature review and an up-to-date and exhaustive bibliography on the AGC of power systems. Various control aspects concerning the AGC problem have been highlighted. AGC schemes based on parameters, such as linear and nonlinear power system models, classical and optimal control, and centralized, decentralized, and multilevel control, are discussed. AGC strategies based on digital, self-tuning control, adaptive, VSS systems, and intelligent/soft computing control have been included. Finally, the investigations on AGC systems incorporating BES/SMES, wind turbines, FACTS devices, and PV systems have also been discussed.

Recent philosophies of automatic generation control strategies in power systems

Efficient algorithms are presented for the solution of two important problems in the area of damping control of electromechanical oscillations in large-scale systems. The proposed algorithms allow the determination of: the most suitable generators for installing power system stabilizers; the most suitable buses in the system for placing static VAr compensators in order to damp the critical modes of oscillation. These algorithms involve the calculation of transfer function residues and represent an important extension of the powerful methodology described by V. Arcidiaconos et al. (see IEEE Trans. Power Apparatus and Systems, vol.PAS-99, p.769-78, 1980), whose use was up to now restricted to power systems of limited size. A major advantage of this methodology is that there is no limitation on the degree of modeling of the power system being studied. >

Determination of suitable locations for power system stabilizers and static VAr compensators for damping electromechanical oscillations in large scale power systems

This paper demonstrates the use of genetic algorithms for the simultaneous stabilization of multimachine power systems over a wide range of operating conditions via single-setting power system stabilizers. The power system operating at various conditions is treated as a finite set of plants. The problem of selecting the parameters of power system stabilizers which simultaneously stabilize this set of plants is converted to a simple optimization problem which is solved by a genetic algorithm with an eigenvalue-based objective function. Two objective functions are presented, allowing the selection of the stabilizer parameters to shift some of the closed-loop eigenvalues to the left-hand side of a vertical line in the complex s-plane, or to a wedge-shape sector in the complex s-plane. The effectiveness of the suggested technique in damping local and inter-area modes of oscillations in multimachine power systems is verified through eigenvalue analysis and simulation results.

Simultaneous stabilization of multimachine power systems via genetic algorithms

Selective Modal Analysis (or SMA) is a physically motivated framework for understanding, simplifying and analyzing complicated linear time-invariant (or LTI) models of dynamic systems [1,2,3]. SMA allows one to focus on any prespecified dynamic pattern of intrest in the model. In particular, One can efficiently and accurately compute the eigene values and eigenvectors of the natural modes of interest and their sensitivities, and also determine physically meaningful reduced order models containing these natural modes. SMA is particularly suitable for dealing with composite models, i.e. models consisting of several dynamic subsystems interrelated by static constraints. An introduction to the basic concepts of SMA pertinent to the applications being considered here is presented in the companion paper [3]. This paper concerns the application of SMA to the Dynamic Stability problem in electric power systems; it is shown how SMA is well suited to meet the demanding requirements of Dynamic Stability analysis. This is illustrated in [3] with examples, including a 60-machine model of a dynamic instability occurrence in an actual power system.

/pdf/selective-modal-analysis-with-applications-to-electric-power-4rzqn9kfrx.pdf

Selective Modal Analysis With Applications to Electric Power Systems, Part II: The Dynamic Stability Problem

This paper addresses the problem of the most effective selection of generating units to be equipped with excitation system stabilizers in multimachine systems which exhibit dynamic instability and poor damping of several inter-machine modes of oscillation. Practical means have been developed using eigenvalue analysis techniques to guide the selection process. The linear state space matrix is derived directly from perturbation of the states of a large scale power system dynamic simulation and a subset of this matrix is used to yield the sensitivity of damping ratios of eigenvalues to stabilization measures in individual machines.

Coordinated Application of Stabilizers in Multimachine Power Systems

Use of accelerating power to provide damping of synchronous machine oscillations through supplementary control of excitation has significant advantages. However, true accelerating power derived from Mechanical and Electrical power presents difficult measurement problems. A practical approach of deriving stabilizing action comparable to that obtainable with accelerating power is described using measurement of electrical power and frequency of a voltage synthesized from machine terminal voltage and current.

Practical Approaches to Supplementary Stabilizing from Accelerating Power

Automatic generation control.

This paper presents a close analysis of the stability of subsynchronous oscillations in a radial series compensated power system. A frequency response analysis is used. The analysis covers varying levels of detail in generator electrical and mechanical modeling and thereby illustrates the mechanism by which subsynchronous oscillations can become unstable. The basic purpose of this paper is tutorial; a companion paper discusses its mathematical basis and full scale application of its method.

Subsynchronous oscillations part 2 &#2014; shaft-system dynamic interactions

HVDC terminals are modeled in load flow and stability programs using certain relationships for real and reactive power derived fran a set of assumptions for fundamental frequency voltages and currents.

J. M. Undrill

Papers

Coordinated Application of Stabilizers in Multimachine Power Systems

Practical Approaches to Supplementary Stabilizing from Accelerating Power

Automatic generation control.

Subsynchronous oscillations part 2 ߞ shaft-system dynamic interactions

Comparing Fundamental Frequency and Differential Equation Representation of AC/DC

J. M. Undrill

Papers

Coordinated Application of Stabilizers in Multimachine Power Systems

Practical Approaches to Supplementary Stabilizing from Accelerating Power

Automatic generation control.

Subsynchronous oscillations part 2 &#2014; shaft-system dynamic interactions

Comparing Fundamental Frequency and Differential Equation Representation of AC/DC

Subsynchronous oscillations part 2 ߞ shaft-system dynamic interactions