A hybrid stochastic-robust bidding model for wind-storage system in day-ahead market considering risk preference

In this paper, a novel hybrid stochastic-robust bidding model for a wind-storage system in the day-ahead (DA) market considering risk preferences is proposed. In the proposed scheme, the uncertainties of wind power and DA electricity price are firstly accounted for through stochastic optimization (SO) and robust optimization (RO) models. Then, to combine the advantages of both SO and RO models, based on the Hurwicz optimistic coefficient, a hybrid stochastic-robust bidding model is formulated for wind-storage systems, where wind farm bidders can select bidding strategies with different risk levels. Additionally, to reflect a more realistic operating cost of Energy Storage System (ESS), the ESS life degradation model based on equivalent full cycle counts is embedded into this hybrid model. To make the proposed non-convex hybrid bidding model computationally tractable, strong duality theory and piecewise linear functions are employed to transform it into a mixed integer linear programming (MILP) problem, which can be efficiently solved with the off-the-shelf optimization software. The simulation results demonstrate that the proposed bidding model effectively handles various scenarios and enables the selection of appropriate strategies under different risk preferences.