Coordinated allocation of distributed generation resources and electric vehicle charging stations in distribution systems with vehicle-to-grid interaction

Abstract

With the implementation of vehicle-to-grid technologies, electric vehicles in distribution systems are becoming controllable resources and enabled to provide a lot of ancillary services (e.g. peak power shaving, voltage regulation, spinning reserve and so on). This phenomenon brings positive effects to the operation of distribution systems but simultaneously challenges the deployments of related power devices, especially the distributed generation resources. Based on this background, this paper proposes an optimization model to jointly deploy electric vehicle charging stations and distributed generation resources, during which the vehicle-to-grid function of electric vehicles is comprehensively considered. To make the optimization model ideally convex, linearized Distflow equations, as well as an exact second order conic relaxation are adopted and utilized in this paper. Consequently, the proposed model can be efficiently solved by off-the-shelf commercial solvers and the allocation schemes with minimal annualized social costs are obtained in polynomial time. Finally, a practical urban area fed by a 31-bus distribution system in China is selected as the test system to verify the effectiveness of the proposed approach, and numerical results are analyzed.