SPICE Simulation of Modal Impedances in Automotive Powertrains under Different Operating Conditions

The spread of information-communication technology (ICT) devices in full and/or hybrid electric vehicles is posing increasing issues about coexistence between communication and electric power systems. Particularly, under different operating conditions, the time-variant and nonlinear behavior of the involved power-electronic devices may cause detrimental electromagnetic interference (EMI) effects for onboard ICT devices. The use of passive or active EMI filters can mitigate EMI, yet their effective design requires the knowledge of the actual modal impedances of the involved components. With the final objective to support EMI filter design, in this work, the frequency response of the common mode (CM) and differential mode (DM) impedances of a complete automotive power train is investigated under different operating conditions. Moreover, both low-frequency functional aspects and high-frequency parasitic effects are considered and modelled properly.