Consensus-Based Coordination of Electric Vehicle Charging

As the population of electric vehicles (EVs) grows, coordinating their charging over a finite time horizon will become increasingly important. Recent work established a framework for EV charging coordination where a central node broadcast a price signal that facilitated the tradeoff between the total generation cost and local costs associated with battery degradation and distribution network overloading. This paper considers a completely distributed protocol where the central node is eliminated. Instead, a consensus algorithm is used to fully distribute the price update mechanism. Each EV computes a local price through its estimate of the total EV charging demand, and exchanges this information with its neighbours. A consensus algorithm establishes the average over all the EV-based prices. It is shown that under a reasonable assumption, the price update mechanism is a Krasnoselskij iteration, and this iteration is guaranteed to converge to a fixed point. Furthermore, this iterative process converges to the unique and efficient solution.