在竞争激烈的电力市场中 各售电主体如何优化交易策略使其收益最大？

从表6横纵向对比可以看出：1)随着不确定集的增大,风险成本呈下降趋势,运行成本呈上升趋势,总收益先增加后减小,在0.3处取得最大。结合2.2节可以看出,随着不确定集增加,风电出力波动区间越大,意味着交易策略能够应对更为极端的风电恶劣场景,因此能有效降低风电波动导致的弃风及切负荷量,进而风险成本随之减少;对运行成本而言,VPP需要加大可控燃气轮机组出力,以保证有足够应对风电波动的动态备用容量,这就导致运行成本增加,系统经济性下降。2)与两阶段鲁棒相比,静态鲁棒的运行成本、风险成本增大,总收益减小。这是因为两阶段鲁棒模型将部分决策变量(如：燃气轮机、可中断负荷等出力)放在内层优化中,能够针对不确定参数情况进行适应性调节,无需提前确定。因此相比静态鲁棒优化,两阶段鲁棒优化交易方案具有更强的抵御风险能力,经济性和鲁棒性得到极大的改善。

为了更清晰的对比两阶段鲁棒优化和静态鲁棒方法的性能,定义如下总收益相对差指标ΔG：

显然,相比静态鲁棒方法,两阶段鲁棒优化具有更好的经济性。随着βW的增大,两阶段鲁棒与静态鲁棒总收益相对差增大,表明两阶段鲁棒优化交易策略更能抵抗系统的不确定性。

5 结论

本文采用多虚拟电厂建立非合作博弈模型,各主体充分考虑其余竞争者的策略影响分别追求利益最大化。通过对整合不同分布式能源的多虚拟电厂系统进行算例分析得到以下结论：1)虚拟电厂整合资源对出清结果有着较大影响,较低的运行成本能够使得虚拟电厂处于低报价水平,在竞标中获得较大成功;2)聚合电动汽车并优化其充放电行为能够稳定虚拟电厂整体出力,提升其在电力市场中的竞争力;3)采用切负荷和弃风成本量化不确定性带来的风险,决策方案需兼顾鲁棒性与经济性,单方面的考虑鲁棒性或经济性都会导致虚拟电厂收益下降。

本文主要围绕电量交互形式进行优化,下一步将对VPP要素进行丰富,跳出以电为中心的思路,重点研究蓄冷蓄热等综合能源服务下的交易策略。

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