Computation of the electromagnetic coupling of parallel untransposed power lines

Computation of capacitive and inductive coupling between parallel circuits of power lines allows determination of induced currents and voltages on the non-energised circuits due to the voltages and currents on the adjacent energised circuit(s). Various computer tools are now available for these computations. However, there is still some uncertainty with regards to accuracy of results and capabilities of each software. For example, some programs have limitations with the maximum number of circuits that can be analysed. These programs first require the line parameters to be determined and then implemented in circuit simulation of the lines including the effect of span length and number and line terminations. In this study, various approaches have been considered and compared namely: SimPowerSystem, EMTP, MicroTran and newly developed routines to calculate the line parameters (R, L, C and Z) required for circuit studies. The calculation principles for each method were examined and correlated to the error analysis.