The refined transmission line model was used to study the distribution of voltage and current along the half wavelength transmission lines under complicated environments.Based on the multiconductor transmission line theory

a piecewise modeling method was proposed.Considering the complicated environments

the distribution parameters of the line are solved

and each section of the circuit was connected in series through the chain parameter matrix.Combined with some UHV line parameters and segments

the influences of the soil resistivity

adjacent line

load impedance and hybrid transmission line on distribution of voltage

current and power along the half wavelength transmission line were analyzed.The calculation results show that the soil resistivity will affect the half wavelength transmission lines in the three-phase asymmetric operation of the lines.The influences of adjacent lines on the half wavelength transmission lines are related to their length

distance

and location.The smaller the load impedance is

the greater the maximum voltage along the half wavelength transmission lines is.The influence of hybrid transmission lines on the half wavelength transmission line is related to the proportion and location of the mixed lines.And the voltage and current fluctuations along the line is greater if the proportion is higher.Through detailed analysis

the sag coefficient 1/3 is still suitable for half wavelength transmission lines.So it is necessary to consider complicated environment and establish a refined transmission line model for half wavelength line.