Electrical Properties of Conductive Electric Roads

Given the global climate crisis, the electrification of road transport has accelerated in recent decades as a strategy to mitigate global greenhouse gas emissions, with the share of Battery Electric Vehicles (BEVs) increasing exponentially. While BEVs provide substantial environmental advantages during their operational phase compared to combustion-powered vehicles, they require an extensive charging infrastructure due to their limited range. Conductive electric roads have emerged as a promising solution, enabling BEVs to charge while in motion, thereby extending their range and reducing the required battery size when deployed on a large scale.

This thesis examines the electrical properties of conductive electric roads, specifically assessing the electrical sliding contact that facilitates energy transfer between the electric road and the vehicle, as well as evaluating the system’s power capabilities, losses, and efficiency in relation to varying traffic characteristics. It also addresses challenges related to conducted Electromagnetic Interference (EMI) within the system and its power grid connection, along with electrical safety concerns related to touch events involving human contact with the vehicles operating on the electric road and the electric road itself.

Key findings show that the electrical sliding contact between the vehicle and the electric road is influenced by numerous factors, making it complex and requiring further research. Preliminary results suggest that the sliding contact design needs improvement, as contact resistance fluctuates and arcing occurs frequently. In terms of the technology’s performance regarding losses, the system demonstrates high efficiency, exceeding 93% across urban, rural, and highway deployment scenarios. The impact of conducted EMI within the system and its power grid connection is found to depend largely on the design of the rectifier station. An analysis of electrical safety related to touch events involving human contact with the vehicle chassis reveals that parasitic capacitive coupling can occur between the chassis and the vehicle’s onboard high-voltage system, posing a potential safety risk.