Shielding Factor Calculation of Mixed Power-lines with The Over-head Transmission Line, Transformer & Cable

In this paper, presented is a shielding factor calculation method of mixed power lines with the over-head transmission line, transformer and cable in urban districts. If the power transformer type is Y0/Y0, the transformer secondary coil circuit is coupled with its primary coil circuit through not only the magnetic steel core but also its ground resistance. An uncoupled algorithm of its ground resistance is proposed. Some example results show that this method is valid and realistic