The THELMA Model of the Joint Resistance Distribution Tests with JORDI

Abstract

In a cable-in-conduit conductor (CICC) operating in DC mode, an uneven current distribution can be present, due to the non-uniform contact resistance between the individual strands and the resistive part of the termination. In the JORDI (JOint Resistance Distribution) facility at CRPP, the contact resistance distribution among the sub-cables (channels) of a large CICC termination was measured in 2006 under conditions of balanced, impressed currents. The voltage was measured between each channel and the mid-plane of the connection with the facility current lead, so a set of channel equivalent resistances were obtained, which depend on the contact non uniformity. This experiment has been simulated with the THELMA code, to investigate its capability to reproduce the equivalent resistance distribution. To this purpose, the termination has been modeled as an equivalent lumped network, in which all the channels are individually represented. The paper describes the model, compares the results of the simulations with the measured values and discusses the influence that the model geometrical and electrical parameters have on the resistance distribution.