Electrostatic Unbalance to Ground of Twin Conductor Lines [includes discussion]

Inductive and capacitive unbalances are present in transmission lines which are not transposed. The modern trend has been to omit transpositions1,2 and it is then desirable to compute the resultant unbalances. This paper deals with one phase of this problem as applied to twin conductor (bundle conductor) lines, namely the electrostatic unbalance to ground which is a result of unequal capacitances between the three phases and ground. In a solidly grounded system, this unbalance manifests itself as a fundamental frequency, zero-sequence current in the lead between the neutral and ground of the power transformer which is used for system grounding.