1 Introduction 2 Electromagnetic Transients 3 Synchronous Machine Modeling 4 Synchronous Machine Control Models 5 Single-Machine Dynamic Models 6 Multimachine Dynamic Models 7 Multimachine Simulation 8 Small-Signal Stability 9 Energy Function Methods Appendix A: Integral Manifolds for Model Bibliography Index

Power System Dynamics and Stability

The authors discuss voltage stability analysis of power systems using static and dynamic techniques. Using a small test system, results of time domain simulations are presented to clarify the phenomenon of voltage instability and to better understand modeling requirements. The same system is then analyzed using a static approach in which modal analysis is performed using system conditions, or snapshots, which approximate different stages along the time domain trajectory. The results obtained using the dynamic and static methods are compared and shown to be consistent. >

Voltage stability analysis using static and dynamic approaches

A combined simulation of transient and long term phenomena in power systems requires the solution of a large nonlinear stiff set of differential-algebraic equations. In this paper, the authors propose the mixed Adams-BDF variable step size and variable order algorithm for solving this problem. The Adams method is applied to the differential state variables: it provides a more reliable detection of stable cases from unstable cases than BDF. The BDF (backward differentiation formulae) method is applied to the algebraic state variables. These are less sensitive to the variations in algebraic equations than the Adams method. This combined Adams-BDF method has been successfully implemented in the EUROSTAG simulation package and sample results are presented in this paper. >

The mixed Adams-BDF variable step size algorithm to simulate transient and long term phenomena in power systems

In this paper, we present a new Matlab-based toolbox for power system analysis, called MatDyn. It is open-source software, and available for everyone to download. Its design philosophy is based on the well-known open-source Matlab toolbox MATPOWER, but its focus is transient stability analysis and time-domain simulation of power systems, instead of steady-state calculations. MatDyn's philosophy, design criteria, program structure, and implementation are discussed in detail. A trade-off is achieved between the flexibility of the program and readability of the code. MatDyn retains overall flexibility by, for instance, allowing user defined models, and custom integration methods. The software is validated by comparing its results with those obtained by the commercial grade power system analysis package, PSS/E. Despite the fact that MatDyn is fairly new, it has already been extensively used in research and education. This paper reports interesting results obtained with MatDyn in recent research that would be hard to obtain using commercial software.

MatDyn, A New Matlab-Based Toolbox for Power System Dynamic Simulation

The electromagnetic transient programs (EMTP-like tools) are based on the nodal (or modified nodal) equations that enable an efficient numerical solution and, subsequently, fast time-domain simulations. The state-variable-based simulation programs, such as Simulink, are also used for studying the dynamics of electrical systems. Both the offline and real-time versions of these two types of simulation tools are widely used by the researchers and engineers in industry and academia to study the transient phenomena and dynamics in power systems with rotating electrical machines. This paper provides a summary of the interfacing techniques that are utilized to integrate the general-purpose models of electrical machines with the rest of the power system network for these studies. The interfacing methods are broadly classified as indirect and direct approaches. The paper also describes the numerical properties as well as limita- tions imposed by the interfacing of the commonly used machine models that should be considered when selecting the simulation parameters and assessing the final results.

Methods of Interfacing Rotating Machine Models in Transient Simulation Programs IEEE Task Force on Interfacing Techniques for Simulation Tools

A program is developed for the numerical simulation of dynamic phenomena in power systems. This program unifies the conventional fields of transient, mid-term and long-term stabilities. The integration algorithm ensures a constant level of accuracy in the calculation of fast or slow transients through a continually variable step and through suitable numerical stability properties. The performance levels reached, both as regards ease of utilization and the size and complexity of the simulated systems, allow the majority of cases to be covered so far as the dynamic system behavior study requirements of the Belgian power companies are concerned. >

J. C. Baader

Papers

STAG-a new unified software program for the study of the dynamic behaviour of electrical power systems