Calculation of AC losses in current forced conductors using 3D finite elements and the A psi V method

A scheme for modelling the current distribution in massive voltage-forced or current-forced conductors is presented. The method is based on a 3-D finite-elements model which use the A psi V field representation. The scheme has been verified by simulating a toroidal choke and comparing the predicted AC losses with experimental measurements. The method has been shown to give reasonable results when applied to the toroidal choke problem, considering that the double helix was idealized as a set of circular conductors. Selectively increasing the order of representation has been shown to be a good technique for modelling skin depth. One disadvantage of the scheme is the number of variables per node, five on the conductor to nonconductor interface. This leads to a relatively dense matrix which is costly to solve.<>