Experimental Characterization and Dynamic Modelling of Electrical Cables

Electric high voltage (HV) cables are commonly used in electrified vehicles. These cables are well known for being potential flanking transmission paths for structure-borne sound in a broad frequency range and must therefore be included in the NVH design process. Although many different layouts exist automotive HV cables fundamentally exhibit a layered structure consisting of a conductive core covered by, in sequence, an isolating sheath, a wire mesh shield to minimize electromagnetic interference and an outer jacket. The conductive core consists of hundreds of thin copper or aluminum wires organized in strands which are wound in a helical pattern. An extensive measurement campaign was carried out to dynamically characterize different cable specimen in terms of multi-degree of freedom transfer impedances. It was shown that although the cable exhibits a direction-dependent Young’s modulus and loss factor suitable results could be obtained by modelling the conductive core using an isotropic multi-layer continuum model. The model was experimentally validated for a test case featuring strong dynamic coupling and showed encouraging results until 2 kHz.