EV Charging Schedule in Coupled Constrained Networks of Transportation and Power System

Large-scale electric vehicle (EV) integration will introduce new challenges to the complex, constrained, and coupled electric power-traffic networks (PTN). In this paper, a coordinated solution for stochastic security constrained unit commitment-traffic assignment problem (SCUC-TAP) is proposed in which stochastic SCUC is used to model the power grid operation with large-scale renewable energy integration, and TAP is used to model the constrained traffic network. The impact of the departure time of commuting EVs on mitigating the congestion in PTN is analyzed based on the proposed model. A heuristic algorithm using Benders decomposition is proposed in which the traffic plan is introduced for decoupling the proposed SCUC-TAP while utilizing the existing software packages of TAP and stochastic SCUC. Two case studies including a 6-bus power system with 9 nodes and 24 directed links traffic network and an IEEE 118-bus system with three independent urban traffic network are used to simulate various scenarios in the coupled networks of power and transportation. The simulation results show that by introducing a flexible EV charge/travel schedule, the power system generation and delivery costs can be further reduced in which most EV users gain from the optimization of transportation, charge/discharge, and power system delivery schedules.