Dynamic Modelling and Mutual Coordination of Electricity and Watershed Networks for Spatio-Temporal Operational Flexibility Enhancement Under Rainy Climates

This paper proposes a watershed-electricity nexus model to unlock the flexibility of watershed networks (WSNs) for supporting the operation of power distribution networks (PDNs) under rainy climates. The proposed model exploits the spatio-temporal flexibility of geographically dispersed pump clusters to provide reserve services to PDNs, and a hyperbolic partial differential function derived from Saint-Venant hydrodynamic equations is formed to describe the dynamic processes of river stream flows. Besides, a flexibility evaluation method based on a composite sensitivity matrix of water levels with respect to power injections is presented to quantify the time-varying adjustable power domain of pump loads. Then, a multi-stage interactive coordinated scheduling strategy is developed for the mutual operation of WSNs and PDNs, where drainage pumps are jointly optimized to provide flexible power reserves, while an optimal PDN economic dispatch is performed to improve the power supply voltage of pump loads. Furthermore, an equivalent mixed-integer linear programming reformulation method is derived to cope with the original nonlinear partial differential optimization problem for computational tractability improvements. Comparative results have validated the effectiveness of the proposed strategy in eliminating voltage violations and shaving peak loads.