Multi-Voltage Domain Communication in Electric Vehicles and Consequences for E/E Architectures

Abstract

The electrical and electronic (E/E) architecture of electrical vehicles (EV) consists of at least two voltage domains where vehicle modules are placed in relation to their application. Some communicate across voltage domains. There is a need to protect humans from dangerous voltages and electronics from damage. Limiting the high-voltage domain to 48 V has safety advantages and avoids the need for galvanic isolation but is of limited use for EVs that require higher supply voltages. Even within 48 V systems, unwanted effects may occur when bridging the 12 and 48 V domains. We show exemplary communication architectures and explain effects between voltage domains that may result in damaged electronic sub-systems. EMC effects are investigated in the context of isolation and study results on noise propagation across voltage domains are discussed.