Collaborative Research: Stability, security and emergency control for reconfigurable networked microgrids

联网微电网(NMG，由太阳能电池板或风力涡轮机供电的家庭或地区级微电网的互联)越来越多地被用于微电网之间的资源共享，这可以提供显著的经济效益。然而，在这种网络环境中，健壮性和脆弱性之间存在着一个鲜为人知的权衡。一方面，多个独立微电网的互联可以提高微电网的稳健性，因为增加的总惯性将允许更好地抑制相对较小的扰动，如负荷和可再生能源的变化或较小的负荷/发电机停电。另一方面，互联还将扩大单个微电网之间的电气和运行耦合，并导致更多的连锁故障路线(例如，任何微电网的局部故障都可能传播到整个网络，威胁到整个网络的脆弱性)。该项目将在以下方面做出贡献：(I)开发联网微电网的高保真模型，为动态分析和控制带来新的应用领域；(Ii)开发易于计算的优化算法，以解决控制行动分析中涉及的稳定性约束的最优潮流问题；(Iii)引入创新的网络重构和有意的孤岛算法，以增强联网微电网的弹性，这可以为其他复杂网络的风险缓解提供参考。在更广泛的背景下，该项目可以在自然灾害或网络物理攻击导致的长时间停电期间帮助保护关键基础设施，例如机场、医院、建筑物。为了填补这一知识空白，该项目将研究联网微电网中稳健性和脆弱性权衡的复杂方面。然后，这一知识允许综合和验证综合预防-纠正业务战略，以实现总体稳健性和脆弱性之间的最佳折衷。技术上，我们将针对最常见的故障，独立分析两种相辅相成的预防-纠正策略，以确保NMG系统的安全。分析这两个控制行动的成本-风险权衡，将导致预防和纠正战略与NMG行动的最佳整合。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Networked microgrids (NMG, e.g., interconnections of house or district level microgrids powered by a solar panel or wind turbine) are increasingly utilized for sharing resources among microgrids, which can offer significant economic benefits. However, there is a poorly understood trade-off between robustness and fragility in this network setting. On one hand, the interconnection of multiple individual microgrids can improve the robustness of the microgrid network since the increased aggregate inertia will allow for better rejection of relatively small disturbances like load and renewable generation changes or minor load/generator outages. On the other hand, the interconnection will also extend the electrical and operational couplings between individual microgrids and lead to more routes of cascading failures (for example, a local failure of any microgrid can propagate throughout the network and threaten the whole network fragility). The project will make contributions in: (i) development of high-fidelity models of networked microgrids, bringing a new application domain to dynamics analysis and controls; (ii) development of computationally tractable optimization algorithms to solve the stability constrained optimal power flow problems involved in the analysis of the control actions; (iii) introduction of innovative network reconfiguration and intentional islanding algorithms to enhance networked microgrids resilience, which can inform innovations in risk mitigation of other complex networks. In the broader contexts, this project can help protecting critical infrastructures, e.g., airports, hospitals, buildings, during prolonged power outages due to natural disasters or cyberphysical attacks. Aiming to fill the knowledge gap, this project will investigate intricate aspects of the robustness-fragility trade-off in networked microgrids. This knowledge then allows for the synthesis and validation of integrated preventive-corrective operational strategies that achieve the optimal compromise between overall robustness and fragility. Technically, we will analyze independently two complementary preventive-corrective strategies for ensuring the security of the NMG system with respect to the most common faults. Analyzing the cost-risk tradeoff of these two control actions will then lead to an optimal integration of preventive and corrective strategies into NMG operations.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.