Communicational aspects in hierarchical real-time control of electric vehicle charging: Available information and its value

Abstract

Smart electric vehicle (EV) charging is a widely studied topic, and multiple different solutions have been proposed in the scientific literature to execute various demand response objectives. However, most studies use assumptions and simplifications that may not hold in real-life situations, and thus, the proposed solutions may have a diminished practical value. Here, communicational aspects of hierarchical EV charging control are studied. The study considers the availability, acquisition, and value of certain information in case of real-time control. The paper illustrates potential pitfalls when using certain assumptions or simplifications in the simulations and proposes a novel algorithm to deal with the lack of preliminary information that exists in real-life situations. The objective of the proposed algorithm is to allow a lower-layer controller to track the real-time controllability of the EVs. This information is necessary in hierarchical control solutions with multiple lower-layer controllers controlled by an upper-layer controller to ensure efficient operation. The simulation results shows that a lower layer controller can estimate the controllability of the EV charging in realistic conditions within 1%–4 % accuracy despite the initially unknown characteristics of EVs.