Introduction of Frequency-Dependent Line Parameters into an Electromagnetic Transients Program

A new method is given for digitally modeling the frequency dependence of the line parameters for an overhead transmission line. Using Fourier transforms, the method models only the line characteristics, leaving the terminations to be chosen by the user. The model of the frequency-dependent line is embedded in a general purpose electromagnetic transients program providing the user with a wide choice of termination and excitation conditions. The method promises to be accurate, and provides insight into the propagation of the aerial and ground modes of transmission. A comparison of line modeling using the method of characteristics, ¿equivalents, and frequency-dependent line parameters is given. Although the frequency dependence has been implemented for only one two-phase line, the method is general in principle.