Impact of HV Battery Cables’ Emissions on the Signal Integrity of 2-Wire Ethernet Communication in Automotive Application

Abstract

Beside the electrification of vehicle traction systems, the implementation of autonomous driving functions is the main future trend in the automotive sector. For the realization of autonomous driving a large number of sensors is required. Due to the large amount of data needed for autonomous driving, the data rates of the conventional communication systems are not sufficient and therefore, new communication systems such as 100Base-T1 are implemented in the vehicle architecture. On the other side, in electric and hybrid electric vehicles, the electrical traction system operates at voltages beyond 400 V in close proximity to the sensors and communication lines. To ensure the electromagnetic compatibility (EMC) of the overall vehicle, the traction system is entirely shielded and isolated form the other vehicle systems. However, the communication channel for the automotive Ethernet is realized using unshielded twisted pair (UTP) cable, which is prone to electromagnetic disturbances. As a result, the EMC coupling between these high voltage (HV) traction systems and the communication channels is an important aspect, which requires a comprehensive investigation. In this work a test setup consisting of an electric vehicle traction system is used in parallel to a 2-wire Ethernet communication via an UTP cable. The setup is used to investigate the impact of the disturbances from HV battery cables on the immunity and the signal integrity of the Ethernet communication.