Will electric vehicles someday be charged as they roll down the highway? Dynamic wireless charging—charging a vehicle as it travels down a specially-equipped road—is still in the research stage, but it seems technologically feasible. A new paper by Cornell researchers examines the possibilities of wireless charging roads equipped with energy storage systems.
Above: A Tesla driving down a two-lane highway, which could be used to wirelessly charge EVs in the future. Photo: Jonathan Varghese / Unsplash
The new work, “Efficient energy management of wireless charging roads with energy storage for coupled transportation–power systems,” was published this month in Applied Energy. Co-authors H. Oliver Gao and Jie Shi argue that integration of wireless charging roads into the existing electricity market and efficient management of the corresponding energy storage system are crucial for successful implementation of dynamic charging.
“In this work, we develop a coupled transportation-power system framework for incorporation of a wireless charging road system into the real-time electricity market,” said Gao, Director of Cornell’s Systems Engineering Program.
The simulation study demonstrates that efficient control of the energy storage system not only reduces the energy costs of the entire wireless charging road system but also alleviates the pressure produced by the wireless charging load on the existing power grid. In two numerical examples, the energy costs are reduced by 2.61% and 15.34%, respectively.
“We designed a Lyapunov optimization-based control strategy to manage the energy flow between the wireless charging roads and the energy storage system in a cost-efficient way,” Gao said.
“The proposed framework is composed of three major modules: the hybrid traffic assignment, the extended DCOPF, and the controller,” Gao explains. The hybrid traffic assignment calculates the traffic flow given specific trips across a road network composed of wireless charging lanes and normal traffic lanes. The extended direct current optimal power flow (DCOPF) determines the optimal electric energy flows between the generation resources, load centers and wireless charging roads in the given power grid. The control approach seeks to minimize the energy costs of wireless charging roads by efficiently managing the output of the energy storage system.