Architectural Challenges of an Electrical Distribution System in Prototype HEVs

Hybrid Electric Vehicle (HEV) prototypes are based off production platforms. Several new systems are added to the vehicle, either to perform hybrid functions or to support them and enhance vehicle performance and fuel economy. All these systems are electrically connected in the vehicle with overlay wiring harnesses. Architecture of overlay wiring harness for the HEV requires identification of new systems and working out their electrical connectivity requirements. This dictates the level of changes required in the vehicle electrical system. Harnesses are built based on the circuit design and location of these systems in the vehicle. EMI requirements, routing and packaging challenges are resolved during the overlay process and testing of the prototype. This paper presents the process of harness design, its architecture and integration challenges in the vehicle.