Dispatch Management of Portable Charging Stations in Electric Vehicle Networks

Abstract The global market share of plug-in electric vehicles (PEVs) is on the rise, resulting in a rapid increase in charging demand in both spatial and temporal domains. The network and coverage of public fixed charging stations (FCSs) are currently constrained by infrastructure costs. As a result, FCSs are not as ubiquitous as traditional gas stations. In addition, as PEVs require a reasonably long time to recharge, waiting times at public charging stations can easily become excessive particularly during busy traffic hours. This paper introduces the new idea of allocating and dispatching portable charging stations (PCSs) in hotspot areas of EV network during busy traffic hours to: i) relieve the burden on FCSs, ii) minimize vehicle waiting times at charging stations, and iii) reduce the overlaps between total PEV demand and peak residential load. We formulate the research challenge for the smart management of PCSs as a constrained optimization problem and introduce a heuristic solution. Detailed simulation results for the Washington green highway EV network show that the proposed approach can significantly reduce the average PEV waiting times and decrease the average PEV loads at FCSs during peak hours by up to 64.7% and 67%, respectively.