Resilience-Based Coordinated Scheduling of Cascaded Hydro Power With Sequential Heavy Precipitation

Abstract

Cascaded hydro units and thermal units play important roles in power systems, and some external weather-related events, e.g., heavy precipitation, have great impacts on hydro power generation, especially in consideration of the cascaded characteristics between different upstream-downstream hydro units, and the coordinated dispatch between hydro units and thermal units constrained by the system network. This article presents resilience-based of thermal units and cascaded hydro units in consideration of sequential heavy precipitation to improve power source resilience. Reduced generated scenarios are used to describe uncertainty of heavy precipitation along the hydropower stations sequentially located on the river and wind power. For the cascaded hydro units, the piecewise linearization technique for two-dimensional and three-dimensional functions are used to address the nonlinear relations among reservoir volume, reservoir forebay water level, reservoir tailrace water, net water head, unit turbined outflow, power outputs, etc. Cascaded hydro unit commitment and thermal unit commitment are conducted with the network constraints. The whole problem is established as a mixed integer linear programming model with an expected operational cost as the optimization objective. Two cases are used to validate the model, and the resilience-based coordinated strategies are demonstrated to improve the power source resilience against sequential heavy precipitation.