Grid demand reduction for high-speed dynamic road charging by narrowing inter-vehicle distance

Dynamic road charging is a technology where electric vehicles (EVs) are continuously charged whilst driving. This technology is seen as an alternative to today's plug-in EV charging infrastructure. The grid that feeds the dynamic road charging system must provide enough power to propel the EVs on the road. With increasing driving speed, more and more power is demanded. Highways therefore require the highest power levels from the grid. For example, charging 10 EVs driving at a speed of 125mph can result in 0.5MW grid demand. The dominant factor that determines power consumption at high speed is aerodynamic drag force. This can be minimised by using aerodynamically streamlined EVs driving in platoons. This paper investigates the impact on grid power levels by varying the inter-vehicle distance of high speed EV platooning. A Simulink model was developed, and it is shown that the grid power level can drop by 40% when 10 EVs are driving in a platoon with an inter-vehicle distance of 0.25 car lengths compared to larger inter-vehicle distance. Short inter-vehicle distance also provides power savings for the front car and, due to autonomous driving technologies, there are no safety concerns.