考虑风电不确定性的分布鲁棒机会约束机组组合模型

Distributionally robust chance-constrained unit commitment model considering uncertainty of wind power

风电渗透率的不断提高大大减少了化石燃料的消耗和温室气体的排放,但风电输出功率的不确定性和间歇性,使传统机组组合问题的解决方法不可行。在此背景下,为了描述风力发电的不确定性,首先,引入一个基于矩信息的椭球式模糊集,并将机会约束运用到机组组合模型中,将功率平衡约束变为软约束;其次,运用分布鲁棒优化方法,将机组组合问题通过线性化方法重构为混合整数线性规划(MILP)问题;并提出限定模糊集中的分布具有单峰性及分时段设定置信度的值的2种改进方法,提高模型的经济性,最后,通过案例分析和仿真结果验证模型与方法的实用性和可行性。

The continuous improvement of wind power penetration has greatly reduced the consumption of fossil fuels and greenhouse gas emissions.However,the uncertainty and intermittent nature of wind power make the solution to the traditional unit commitment infeasible.In order to describe the uncertainty of wind power generation,this paper introduces an ellipsoid ambiguty set based on moment information,and applies the chance constraint to the unit combination model to change the power balance constraint into a soft constraint.Then,the distributionally robust optimization method is utilized,and the unit commitment model is reformulated into a mixed integer linear programming problem by linearization method.In addition,two improved methods,the limiting the distribution of ambiguty set with unimodality and adjusting confidence level according to time,are proposed to improve the economics of the model.Finally,case analysis and numerical results verify the practicality and feasibility of the proposed model and method.