A structured matrix method for determining the phase impedances of 3-phase, 3-dimensional bus layouts

The problem of efficiently formulating and computing the phase impedances of 3-phase, 3-dimensional bus structures is considered. The coupled circuit method, previously used for 2- D eddy current problems in which the circuit elements were simply connected, is extended to the case where the elements, all of which are inductively coupled, can have an arbitrary series/parallel connection. Particular attention is given to the terminal constraints imposed by a 3-phase supply. The development of the system equations is detailed. The method is particularly attractive for use in CAE/CAD applications.