Distributionally Robust Optimization Dispatch Model For Wind Farms And Storage Units Jointly System Considering Wind Power Uncertainty

As large-scale wind farms connected to the grid,the problems of uncertainty and volatility have brought new challenges to the field of power system dispatching.The rapid development of energy storage technology provides new solutions for improving the level of the wind power accommodation.Through the coordinated operation of energy storage and wind farms,the wind curtailment can be significantly reduced and the controllability of the system can be hugely strengthened.Therefore,it is necessary to make a deep research on the optimal dispatch of wind farms and storage jointly system considering wind power uncertainty.Firstly,this paper explains the basic characteristics of the robust optimization model,analyzes the construction strategy of the uncertainty set and the conservative control method.After that,the corresponding solution ideas are listed.Considering the problem of excessive conservativeness for the robust optimization model,the relevant knowledge of the mathematical model of distributionally robust optimization is introduced.Also its mainstream modeling methods are sorted out and discussed.Then,the uncertainty set considering spatial and temporal constraints of wind power is introduced to describe the fluctuation characteristics of random variables.And a robust optimization dispatch model of the wind farms and storage jointly system is proposed.In order to overcome the difficulty for solving the large-scale nonlinear programming problem,linearization methods and nested C&CG algorithm are used to improve the efficiency of model calculation.The results of the simulation example prove that when the uncertainty set takes the time smoothing effect and spatial clustering effect of wind power into account,the dispatching plan is more rational and accords with actual operation of the power system.Finally,based on the norm ambiguity set and the effective information of historical data,a distributionally robust dispatch model for wind farms and storage jointly system is constructed.Compared with the robust optimization model,the distributionally robust optimization model no longer simply represents the fluctuation range of the uncertainty variable in the form of a boundary set,but models the wind power information by defining the distance between the actual probability distribution and the empirical probability distribution.Aiming at the independent characteristics of model scenarios,the dual-free C&CG and parallel method are applied to accelerate the calculation efficiency.The simulation results of the IEEE39-bus system show that the distributionally robust optimization model makes a good balance between the economy and conservativeness of system operation.