Method for Measuring and Analyzing the Transfer Path of Acoustic Phenomena into the Driver Cabin of a Battery Electric Vehicle

摘要

The driving comfort is an important factor for buying decisions. Especially for battery electric vehicles (BEV) the acoustic quality is an elementary distinguishing feature, since the masking of an internal combustion engine (ICE) is no longer present. Opposing the importance of the acoustic quality is the lack of knowledge of how to measure and interpret the high frequency noise generated by an electric powertrain with respect to the NVH behavior influencing the passengers [1, 2]. In this contribution a method for measuring and interpreting the transfer path of acoustic phenomena from the drivetrain of a battery electric vehicle into the passenger cabin is presented. Due to the lack of masking by the ICE in case of BEV, high frequency phenomena must be considered as well. In order to determine the airborne transfer function from the electric powertrain to the driver cabin, a dodecahedral speaker is used for reciprocal measurements. Therefore in a first step, the sound power and the emission characteristic of the dodecahedron is investigated in a novel approach by laser scanning vibrometry and by measurements according to DIN EN ISO 3745:2012 [3]. The results of the reciprocal measurements are validated by calculating the direct transfer path with the help of an order section analysis and comparing those results to measurements on the semi-anechoic roller test bench.