一种计及概率风险的备用优化方法

A risk-based probability reserve optimization method

提出一种计及概率风险的备用优化方法,促进机组组合决策中火电机组与储能系统的合作与协调。通过建立两层优化模型实现日前机组组合配置和实时风险备用调整的协调与迭代求解。日前机组组合计算发电计划、储能计划和备用配置,实时备用优化基于条件风险价值(conditional value-at-risk,CVaR)指标计算不确定性引起的备用需求,体现了调度结果的概率优性,以可靠性和经济性相互牵制与协调的折中决策为手段,用与储能配合的方法来缓解或消除风电不确定性。所提方法验证了储能在降低火电机组备用容量的同时,减少了机组频繁的启停,从而降低系统运行的成本。同时,该方法还可以配合风力发电,降低弃风以及切负荷的风险,增强电网运行的可靠性。最后通过6节点系统与确定性风险备用方式进行比较,验证了所提概率风险备用优化模型的有效性。

A riskbased probability reserve optimization method was proposed to quantitatively evaluate requirement of reserve,which could enhance the cooperation and coordination of the thermal units and the energy storage system in the decision making of unit commitment.A twolayer optimization model of risk constraint unit commitment model and risk reserve decision model was established and solved by iteration.Dayahead unit commitment was used to calculate plans of generation,energy storage system and reserve configuration.The conditional value at risk was applied to calculate the demand of reserve caused by uncertainty of wind power.It was shown that utilization of energy storage system could decrease the reserve capacity of thermal units,reduce the frequency of units'startup and shutdown,decrease cost of system operation,and it could reduce the risks of wind curtailment and load shedding,enhance the reliability of power system with cooperation of wind power.At last,a 6bus system was used to verify the validity in comparison with a determinacy method of risk reserve.