Transfer path analysis and prediction of range extender noise in electric vehicles: From bench tests to cabin acoustics

Interior noise is a key indicator of the quality and noise, vibration, and harshness (NVH) performance of new energy vehicles. In range-extended electric vehicles, the range extender serves as a critical powertrain component whose vibro-acoustic characteristics significantly affect in-cabin acoustic comfort. Owing to the complexity of vibro-acoustic transmission paths, existing studies have primarily focused on vehicle-level transfer path analysis, while reliable prediction of cabin noise from bench-test responses remains challenging, limiting early-stage NVH evaluation and optimization. To address this issue, this paper develops an engineering workflow for bench-to-cabin transfer path analysis of range extenders in new energy vehicles. The structure-borne and airborne transmission paths are first modeled independently and their contribution synthesis mechanisms are characterized. Based on transfer path analysis theory, the bench and vehicle environments are decoupled to independently characterize the structural excitation characteristics and equivalent airborne radiation characteristics of the range extender. Subsequently, a bench-to-cabin transfer path analysis prediction model is established through component transfer function assembly, enabling bench-to-cabin prediction of interior noise. Experimental results show that the proposed model can generally reproduce the variation trends of sound pressure responses at the driver and passenger ear positions. Furthermore, the model is preliminarily validated under an additional operating condition and with an alternative range extender configuration using the same vehicle body and mounting system, indicating its preliminary transferability. The proposed approach provides a potential engineering workflow for the early-stage assessment of range-extender vibro-acoustic performance based on bench measurements.