Risk-aware Distributed Optimal Power Flow in Coordinated Transmission and Distribution System

Active distribution grids cause bi-directional power flow between transmission system (TS) and distribution system (DS), which not only affects the optimal cost but also the secure operation of the power system. This paper proposes a hybrid co-ordination method to solve risk-aware distributed optimal power flow (RA-DOPF) problem in coordinated transmission and distribution system. For operational risk evaluation, weather-based contingencies are considered in both TS and DS. A hybrid coordination method is developed that entails analytical target cascading (ATC) and benders decomposition(BD). More-over, risk-aware optimal power flow in TS and risk-based security constrained optimal power flow in DS, have been performed using the BD method considering basic optimal powerflow (OPF) as a master problem whereas N-1 and N-2 contingencies as sub-problems. Different case studies are performed using the IEEE 30-bus system with generation reserves as a transmission system and a 13-bus system as a distribution system. Results depict the efficacy of the proposed method.