TABLE OF CONTENTS This chapter summarizes some of the fundamental concepts necessary to appreciate the workings of the component parts of a transmission and distribution power system. It is assumed that the reader will already have been introduced to these topics in a theoretical manner during his or her student days. It is therefore a recap of the main points and the practical application of mathematical methods to the solution of real engineering problems. Examples are, therefore, included throughout this chapter.
The following symbols are used throughout this book:
| C | Capacitance | (farads, ?F, etc.) |
| E | Electromotive force emf. | (volts, kV, etc.) |
| f | Frequency | (Hz) |
| H | Inertia constant of a machine | (MJ/MVA rating) |
| h | h operator or 120 operator | (h = ?0.5 + j0.866) |
| I, I r, I r 1 | Current, red phase current, red phase positive sequence current | (amps, kA, etc.) |
| J | Moment of inertia or work | (kgm 2) (joules, Nm, etc.) |
| j | j operator or 90 operator | ( j 2 = ?1) |
| L | Inductance | (henrys, mH, etc.) |
| n | Speed | (rev/s, etc., n = ?/2 ?) |
| P | Active power = UI cos | (watts, kW, MW 1 horse power = 746 watts) |
| pf | Power factor ? cos | |
| Q | Reactive power = UI |
