Line parameters vertical conductor

To analyze a transient in a distributed-parameter line, a traveling-wave theory is explained for both single- and multiconductor systems. A method to introduce velocity difference and attenuation in the multiconductor system is described together with field test results. Impedance and admittance formulas of unusual conductors, such as finite-length and vertical conductors, are also explained. 

Most transmission lines in Japan are of double-circuit vertical configuration with two GWs and are thus composed of eight conductors. The use of a frequency-dependent line model is recommended in a numerical simulation, but a distributed line model with fixed propagation ve-locity, attenuation, and surge impedance, that is, the fixed-parameter dis-tributed line model explained in Reference 23, is often used. 

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