Research on equivalent modeling methods for electromagnetic compatibility of vehicle-mounted harnesses

The interconnection harness undertakes the critical task of power and signal transmission between in-vehicle electronic devices, and its electromagnetic compatibility (EMC) constrains the safety of vehicle systems. As the number of in-vehicle electronic devices increases and wiring becomes increasingly complex, the electromagnetic interference (EMI) issue between cables has become more prominent. Multiconductor transmission line (MTL) models suffer from limited computational efficiency when applied to the electromagnetic analysis of complex automotive wire harnesses. Although the equivalent cable bundle method (ECBM) offers an effective means of model reduction, it is commonly developed under the assumption of an ideal infinite conducting ground plane, which restricts its applicability in realistic vehicular environments characterized by finite metallic boundaries. To overcome this limitation, this paper presents an enhanced electromagnetic modeling approach within the ECBM framework, in which the effects of orthogonal finite metallic boundaries are explicitly incorporated into the per-unit-length parameter extraction. The proposed method is therefore well suited for automotive electromagnetic environments dominated by a limited number of nearby metallic structures. Simulation results demonstrate that compared with the MTL model, the proposed method can accurately predict crosstalk responses and radiation characteristics, with the simulation efficiency improved by approximately 50%. This method provides a new solution for vehicle EMC design and analysis.