间歇性可再生能源发电大量接入电力系统对系统运行灵活性提出了很高的要求。为解决实时调度中系统爬坡和滑坡能力不足问题，美国的一些独立系统运行机构（independent system operator， ISO）提出了一种新的电力市场产品——灵活调节产品（flexible ramping product， FRP），即通过预留额外的灵活性容量来满足系统可能的爬坡和滑坡需求，从而提高系统运行灵活性以便应对多种运行情况。首先，介绍电力系统运行灵活性的基本概念和相关问题，指出在任意时间尺度和多种复杂运行情况下能够保证供需平衡是系统具备高灵活性的重要特征之一，并分析了高比例可再生能源发电接入对系统运行灵活性的影响；接着，介绍灵活调节产品的基本概念、产品特点、定价机制和出清模型，并将其与现有的一些辅助服务进行比较；之后，通过2个算例直观展示灵活调节产品在提高电力系统运行灵活性方面的作用；最后，概述灵活调节产品的研究现状，并对未来灵活调节产品的研究进行展望。

With the ever-increasing penetration of intermittent renewable energy generation， the operation flexibility of a given power system is more and more demanded. To address the issue of insufficient upward and downward ramping capability in real-time dispatch， flexible ramping product （FRP） has been proposed and initially implemented by some independent system operators （ISOs） in the United States as a new market design. The main function of FRP is to explore flexible capability from dispatchable resources so as to meet potential upward and downward ramping requirements， and thus to enhance power system operation flexibility for effectively responding to various operation conditions. The basic concepts and related subjects of power system operation flexibility are first clarified， and it is pointed out that the ability to maintain the balance between power supply and power demand at all time scales under credible complex scenarios is one of the important characteristics of strong operation flexibility. Besides， the impacts of high penetration of intermittent renewable energy generation on power system operation flexibility are examined. FRP is then introduced with the focuses on basic concepts， main characteristics， pricing mechanism and clearing models， and comparisons with the existing ancillary services are made as well. Furthermore， two case studies are served for demonstrating the implementation of FRP in enhancing power system operation flexibility. Finally， the current research status of FRP is outlined， and prospects on FRP-related subjects to be studied presented.

随着可再生能源装机规模快速增长,灵活性需求规律随之转变,同时电化学储能等灵活性资源技术、经济性也随之改善。如何在规划中兼顾灵活性需求演化规律与储能技术发展对提升系统灵活性与经济性至关重要。为此,文章开展了考虑灵活性需求演化规律的灵活性资源动态规划方法相关研究。首先,分析了可再生能源渗透率增长与灵活性供需间演化关系,揭示了多阶段灵活性资源规划的原理及影响因素;然后,考虑灵活性需求演化规律与储能技术经济性持续改善,构建了多阶段灵活性资源优化配置模型,并给出了模型的求解思路;最后在算例中兼顾未来储能技术经济性持续改善与火电机组逐步退出的双重成本,验证了多阶段灵活性资源优化配置方法的可行性和有效性,为未来风电的协调发展提供了指导性的建议。

With the rapid growth of renewable energy installation capacity, the law for flexibility of demand changes, and the economy of flexible resources improve alongside technology, as in electrochemical energy storage. The method of balancing the evolution of flexibility requirements and development of energy storage technology during planning, is crucial in improving system flexibility and economy. Therefore, this study conducts research on the dynamic planning method of flexible resources, considering the evolution law on flexibility of demand. First, the evolutionary relationship between renewable energy penetration growth and flexible supply and demand is analyzed, and the principle and influencing factors of multi-stage flexible resource planning are revealed. Then, considering the evolution law on flexibility of demand and the continuous improvements in energy storage technology economy, a multi-stage flexible resource optimization allocation model is constructed to offer a solution. Finally, the feasibility and effectiveness of the multi-stage flexible resource optimization allocation method are verified by example, considering the continuous improvement of energy storage technology economy and the gradual withdrawal of thermal power units, which provides guidance for the coordinated development of wind power in the future.

目前,虚拟电厂与主动配电网的耦合联系进一步加深,针对含有虚拟电厂市场主体的主动配电网优化调度问题,有必要研究系统内多种灵活性资源与虚拟电厂中不确定性因素在不同时间阶段的协调互动。以主动配电网综合成本最小化和虚拟电厂市场收益最大化为目标,提出一种计及虚拟电厂市场交易的主动配电网日前-实时两阶段调度方法。日前阶段,基于系统灵活性边界,构建了综合考虑网侧灵活性资源协调调度和虚拟电厂日前出清的双层优化模型;在此基础上,实时调整虚拟电厂竞标方案和主动配电网运行策略。最后,在改进IEEE 33节点系统中进行仿真试验,结果表明:所提模型可以有效提升虚拟电厂交易竞争力和配电网运行灵活性水平,可为未来电网市场化发展下的优化调度提供参考。

At present, the coupling of virtual power plant (VPP) and active distribution network (ADN) has been further deepened. Aiming at the optimal dispatching problem of ADN with VPP as a market participant, it is necessary to study the coordinated interaction between various flexible resources in ADN and uncertainty factors in VPP in different time stages. On this basis, with the goal of minimizing the comprehensive cost of ADN and maximizing the market revenue of VPP, a two-stage dispatching method for ADN considering VPP transaction is proposed. In the day-ahead stage, according to the flexibility boundary of the system, a bi-level optimization model is established considering the dispatching of flexible resources in ADN and day-ahead clearing of the VPP. On this basis, the bidding scheme of VPP and the operation strategy of ADN are adjusted in real time. Finally, an improved IEEE 33-node system is taken as an example for simulation analysis, and the results show that the proposed model can improve the market competitiveness of VPP and the operational flexibility of distribution networks both, which provides a reference for optimal dispatching under the future marketization development of power grid.