Bi-Level Continuous-Time Model for the Coordinated Operation of Coupled Electric Power Transmission and Energy Storage Transportation Systems

Energy storage will play an essential part in substantiating the role of renewable energy in decarbonization by providing a new conveyer for energy transportation in electric power systems (EPSs). Different from conventional electric power transmission systems, which can deliver electricity instantaneously, storage transportation is usually affected by issues like the availability and sizes of roads and vehicles, traffic congestion, and vehicle departure and arrival schedules. This article studies the coordinated operation of coupled electric power transmission and storage transportation systems as the world increases the proliferation of variable renewable energy in EPSs. First, we discuss and compare different methods for energy transportation and delivery. Then the hydrogen transportation via delivery tube trailers (DTs) is modeled as a vehicle routing problem (VRP). Accordingly, the coordinated operation of the coupled electric power transmission and storage transportation network (CPSTN) is modeled and reformulated as a mixed-integer linear programming (MILP) problem. To overcome the computational burdens of CPSTN, we propose a bi-level decomposition algorithm. In the outer loop, Lagrangian Relaxation (LR) is adopted to coordinate the power grid operation and DT schedules on different routes, while DT routing is managed in the inner loop by a relaxed branch and pricing (B&P) method. The case studies presented on the modified IEEE-RTS have verified the validity and effectiveness of the proposed method in CPSTN applications for decarbonizing the electricity supply.