Modeling the Integration of Complex EV Systems into NVH Treatments Using Sound Phonons 2023-01-1051

Current and future EV’s contain significant amounts of complex electrical hardware, including rechargeable energy modules, control units, cooling systems and wiring situated inside the cabin usually below the carpet , seats or trunk trim and below the cabin floor. These items, whilst likely to have a direct impact on transmission loss, are increasingly difficult to evaluate via typical methods of computer based simulation. The packaging space allocated for control units which may require an air gap between the Body in white and the carpet for aspects of heat stabilization can be problematic. These gaps introduce complex noise transmission within the carpet which tend to exclude simulation using transfer matrix method (TMM) NVH lay-up models. Also in the case of battery installations their high bulk mass doesn’t necessarily transpire to a large expected increase in the floor systems transmission loss. The accurate prediction of these systems requires advanced modeling techniques. This paper examines each step starting with the individual body systems, where optimization of the NVH package was conducted using Genetic Algorithm solvers. Then transferring to a “full vehicle” model constructed within the same GUI environment where the body system models effect on the sound propagation transfer function from the cabin to the EV motor drive and converter units were evaluated. This method is useful both for the study of future electrification of an ICE vehicle platform as well as “clean sheet” EV design.