ABSTRACT
This chapter presents basic techniques for calculation of the inductive reactance of transmission lines. A transmission line is a complicated structure, comprising more than one conductor. The chapter characterizes each conductor with its inductance and also any pair of conductors with a mutual inductance. It also introduces the basic concepts by considering the magnetic field of an infinitely long conductor of circular cross section. The chapter then examines the magnetic field around a configuration consisting of two circular infinitely long and parallel conductors. The method of geometric mean distances is a simplification and algorithmization of the theory developed so far. It permits fast and accurate computation of the inductive reactance of a line consisting of complicated conductor structures. Bundle conductors are used on extra-high-voltage transmission lines for two reasons: to reduce the inductive reactance of the line, and to reduce corona phenomena. The chapter examines the effects of conductor bundling on the inductive reactance of the line.
