A New Method for Calculating Electric Field Intensity on Subconductors in Unconventional High Voltage, High Power Density Transmission Lines

The electric field intensity on subconductors is the most important parameter to consider when electrically designing (extra) high voltage, (E)HV, transmission lines. In this regard, it is not possible to use existing formulae for calculating electric field intensity on subconductors, which are for subconductors placed symmetrically on bundle circles, for recently introduced unconventional high power density lines where subconductors can be located in unsymmetrical or at any location in the space. Further, in existing formulas, nearby (other phases) and image conductors are ignored, and a uniform field is assumed despite the fact that electric fields are distorted in the presence of other subconductors in a bundle. None of the mentioned assumptions are valid for unconventional high power density lines, so it is necessary to develop an innovative method for calculating electric field on subconductors on these new lines. In our method,
$n_{m}$
line charges for each subconductor are employed to set the electric potentials of
$n_{m}$
points at the periphery of that subconductor equal to the applied voltage. The line charges are uniformly distributed around a hypothetical cylinder with a radius of
$r/2$
, where
$r$
is the radius of that subconductor. The challenge is choosing a proper
$n_{m}$
, leading to an accurate result.