考虑时空耦合的小水电富集型虚拟电厂优化调度策略

Optimal Dispatching Strategy of Small Hydropower Enriched Virtual Power Plant Considering Temporal-Spatial Coupling

流域小水电可通过虚拟电厂(VPP)聚合技术实现统一调度,提升小水电整体的运行可控性,有利于VPP的经济运行。针对小水电富集型VPP(SHEVPP,即含数量繁多且集中分布的小水电的VPP),提出一种综合考虑小水电富集的全流域网络上下游相邻水电站出力和站间流量时空耦合关系的SHEVPP优化调度策略。首先,针对小水电的出力时空耦合特性进行精准有效建模,提出了基于欧氏距离的水电站间水流时滞评估方法以及基于Copula联合分布的小水电出力时空耦合模型;其次,考虑小水电富集的复杂全流域网络拓扑的有效建模,提出了表征流域网络拓扑的矩阵定义方法,实现小水电流量时空耦合特性的精细构建;然后,以考虑条件风险价值(CVaR)的VPP运行收益最大化为目标,构建了考虑时空耦合特性的SHEVPP的优化调度模型,实现考虑VPP风光出力和小水电天然来水流量不确定性的风险调度;最后,以中国某SHEVPP为例对所提模型进行了有效性验证。算例结果表明,所提方法可在小水电时空耦合特性有效建模的基础上,利用多种灵活性资源的协调互补优势,实现VPP运行收益的最大化。

Small hydropower stations in the same basin can realize the unified dispatching through the virtual power plant(VPP)aggregation technology to improve the overall operation controllability of small hydropower stations, which is conducive to the economic operation of VPP. An optimal dispatching strategy of small hydropower enriched VPP(SHEVPP, VPP with numerous and distributed centralized small hydropower) is proposed, which comprehensively considers the temporal-spatial coupling relationship between the output of upstream and downstream adjacent hydropower stations and the water flow between the stations in the whole basin network. Firstly, aiming at the accurate and effective modeling of the temporal-spatial coupling characteristics of the hydropower station output, a method to evaluate the time-lag of water flow between hydropower stations based on the Euclidean distance is proposed, and the temporal-spatial coupling model of the small hydropower output based on the Copula joint distribution is constructed. Secondly, in consideration of the efficient modeling of the complex whole-basin network topology with enriched small hydropower, a matrix definition method is proposed to characterize the water basin network topology, which can achieve the sophisticated modeling of water flow temporal-spatial coupling characteristics of small hydropower. Then, in order to maximize the operation revenue of VPP considering conditional value-at-risk(CVaR), an optimal dispatching model of SHEVPP considering temporal-spatial coupling characteristics is constructed, which will realize the risk dispatching considering the uncertainty of wind power and photovoltaic output of VPP and the uncertainty of the natural inflow of the small hydropower.Finally, case studies on a SHEVPP in China are performed for verifying the effectiveness of the proposed model. The results show that the proposed method can maximize the operation revenue of the VPP by using the coordinated and complementary advantages of multiple flexibility energy resources on the basis of the effective modeling of the temporal-spatial coupling characteristics of small hydropower.