Optimization of Inter-Regional Flexible Resources for Renewable Accommodation

The HVDC tie-line has been successfully transfer- ring the renewable from rural areas to load centers. In the meantime, it is able to provide inter-regional flexibilities as well when flexible resources are located at different regions, maximizing the utilization of flexibility. This paper proposes a two-stage model for the medium-term flexibility planning, which considers the HVDC tie-line schedule, storage deployment, and unit retrofit. In the first stage, storage capacity, fossil-fired unit flexibility retrofit, and scheduled power for tie-line are determined. In the second stage, uncertainties are modeled and accommodated by inter-regional storages and fossil-fired units. Chance-constrained load shedding and renewable curtailment are modeled, avoiding the redundancy of energy storage investment. Simulation results show the efficiency and effectiveness of the proposed approach on promoting the inter-regional renewable accommodation.