The physics of electric power systems

ABB Switzerland, Corporate Research, CH-5405, Baden-Dättwil, Switzerland

Abstract

The article describes electric power systems from a physicist’s point of view. In contrast to common introductory textbooks on power systems, the emphasis is on the physical design, that is the material selection and the choice of the geometrical shape, of the fundamental components as it follows from the function and serves the main purpose. Why do power system components look the way they look? This is the question addressed in an accessible way. Four fundamental components are needed to make the most elementary power system: overhead transmission lines, transformers, synchronous generators, and circuit breakers. High-voltage overhead lines make efficient long-distance transmission of electric power possible. Transformers step up the power from the generating plant and cascade it down to the final consumption. For their ability to control, independently, real and reactive power, synchronous generators are the most common type of generators. And it is only through the immediate extinction of plasma arcs in circuit breakers that shortcircuit currents can be interrupted and faulty segments of the grid disconnected.