CyberSEES: Type 1: A New Reliability-Assuring Computational Framework for Grid Operations under High Renewable Penetration

尽管可再生发电被认为是可持续未来的关键，但风能/太阳能发电在高渗透率水平下的变异性和不确定性对电网可靠性构成了前所未有的挑战。在今天的电力系统中，可靠性是通过分析一系列意外事件来评估的，例如发电机或输电线路的损失。然而，这些基于偶然性的方法在大型风能/太阳能倾斜事件中是不够的，这些事件在可再生能源渗透率高的情况下变得越来越频繁和重要。具体地说，不应将大型风能/太阳倾斜事件视为单一的应急事件。相反，它必须被建模为一个在时间上顺序揭示的不确定事件序列；然而，尽管未来存在重大不确定性，系统操作员必须在这样的事件序列中立即采取行动。由于这一关键差异，传统的基于应急的方法不再能准确地量化在高风能/太阳能渗透率下对可靠性的资源需求，导致资源调度成本更高，以抵消管理不善的不确定性。为了应对这一开放的挑战，这个CyberSEES项目开发了一个新的、在数学上严格的计算框架，用于采购和调度受限的网格资源，其目的是在可再生能源渗透率较高的情况下确保可靠和经济的网格运营。该项目综合了分钟/小时时标(用于平衡需求和供应)和秒/亚秒时标(用于动态安全评估)的可靠性分析。具体地说，项目组开发了确保可靠性的在线算法，用于以分钟/小时为时间尺度的日头机组组合和实时经济调度，可证明在大型和不确定的风能/太阳能倾斜事件下平衡需求和供应。此外，在线算法与计算效率高的基于集合的可达性分析紧密地结合在一起，用于评估秒/亚秒时间尺度的动态系统安全性，这为存在风/太阳不确定性的动态系统状态提供了保证范围。该项目的成功将导致我们在可再生能源渗透率高的情况下确保电力系统可靠性的能力发生翻天覆地的变化。在更广泛的范围内，这些成果将有助于在全球范围内更多地采用可再生能源，并将使之能够顺利过渡到可持续的未来电网。开发的计算框架也将适用于占地面积小的电力系统，如远程微电网。此外，研究结果有望通过推进在线算法设计和可达性分析来促进计算，这也将对其他学科有用。这项工作的成果将通过会议和期刊出版物广泛传播，并积极与业界分享。

While renewable electricity generation is considered key to a sustainable future, the variability and uncertainty of wind/solar generation at high penetration levels pose unprecedented challenges to grid reliability. In today's power systems, reliability is assessed by analyzing a set of contingency events, such as the loss of generators or transmission lines. However, these contingency-based methods are insufficient under large wind/solar ramping events, which become increasingly frequent and significant at high renewable penetration. Specifically, a large wind/solar ramping event should not be treated as a single contingency event. Rather, it must be modeled as an uncertain event-sequence that is sequentially revealed in time; yet the system operator must take immediate actions in the midst of such an event-sequence despite significant future uncertainty. Due to this critical difference, traditional contingency-based methods can no longer accurately quantify the resource requirement for reliability at high wind/solar penetration, leading to more costly dispatch of resources to offset poorly-managed uncertainty. To address this open challenge, this CyberSEES project develops a new and mathematically rigorous computational framework for procuring and dispatching constrained grid resources, which aims to provably ensure reliable and economic grid operations under high renewable penetration. The project integrates reliability analysis at both the min/hour time-scales (for balancing demand and supply) and the second/sub-second time-scales (for dynamic security assessment). Specifically, the project team develops reliability-assuring online algorithms for day-head unit commitment and real-time economic dispatch at the min/hour time-scales, which provably balance demand and supply under large and uncertain wind/solar ramping events. Further, the online algorithms are tightly integrated with computationally-efficient set-based reachability analysis for assessing dynamic system security at the second/sub-second time-scales, which provides guaranteed bounds for dynamic system states in the presence of wind/solar uncertainty. The success of this project will lead to paradigm-shifting advances in our ability to ensure power system reliability under high renewable penetration. At a broader scale, the results will contribute to the increased adoption of renewable energy sources worldwide, and will enable a smooth transition path to a sustainable future grid. The developed computational framework will also be applicable to small-footprint power systems, such as remote microgrids. Further, the results are expected to contribute to computation by advancing online algorithm design and reachability analysis, which will also be useful to other disciplines. The results of this work will be widely disseminated through conference and journal publications and actively shared with industry.