Basics of Power Systems Analysis

This chapter provides the background required to understand the main aspects of power systems analysis and operation under steady-state and transient or dynamic conditions. It is intended for senior undergraduate or graduate students of electrical engineering as well as practitioners, so readers are assumed to have a solid background knowledge of electrical engineering. The main technical issues associated with power systems analysis are addressed, focusing in particular on alternating current (alternating current (AC)) transmission lines, networks, load-flow and short-circuit calculations, stability analysis, frequency control, and electromagnetic transient appraisal. The chapter also references the most important and popular model frameworks and calculation/modeling tools that have been developed by researchers and engineers working within the electric power systems area in the last few decades. It is emphasized in this chapter that an understanding of the issues dealt with here is required to comprehend other chapters of this handbook devoted to distributed generation and smart grids, and this knowledge will also be needed to be able to operate upcoming power systems. The chapter is divided into sections focusing on the following topics: 1.Power systems evolution, from the origins to the traditional structure2.Transmission lines in steady state, transmitted active and reactive power3.Power flow analysis (load-flow equations and resolution methods)4.Short-circuit calculations for unbalanced faults (symmetrical components, fault equations, and sequence networks)5.Stability (states of operation, classification, P-delta curves, rotor angle stability, equal area criterion, multi-machine stabilty and voltage stability)6.Generators reserve and dynamics, frequency dependence of the load, control structure for frequency control7.Traveling waves in a lossless line, reflection and transmission coefficients, multiple reflections in a line of fine length; electromagnetic transients (classification of transients, electromagnetic transient (EMTP))8.Power systems in the future (why we need a smart(er) grid, microgrids and energy communities) Additional information and supplementary exercises for this chapter are available online