Multienergy systems (MES), in which multiple energy vectors are integrated and optimally operated, are key assets in low-carbon energy systems. Multienergy interactions of distributed energy resources via different energy networks generate the so-called distributed MES (DMES). While it is now well recognized that DMES can provide power system flexibility by shifting across different energy vectors, it is essential to have a systematic discussion on the main features of such flexibility. This article presents a comprehensive overview of DMES modeling and characterization of flexibility applications. The concept of “multienergy node” is introduced to extend the power node model, used for electrical flexibility, in the multienergy case. A general definition of DMES flexibility is given, and a general mathematical and graphical modeling framework, based on multidimensional maps, is formulated to describe the operational characteristics of individual MES and aggregate DMES, including the role of multienergy networks in enabling or constraining flexibility. Several tutorial examples are finally presented with illustrative case studies on current and future DMES practical applications.

中文翻译：

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分布式多能源系统的灵活性

多能源系统 (MES) 将多个能源向量整合并优化运行，是低碳能源系统的关键资产。分布式能源通过不同能源网络的多能源交互产生所谓的分布式 MES (DMES)。虽然现在人们普遍认识到 DMES 可以通过在不同的能量向量之间转换来提供电力系统的灵活性，但对这种灵活性的主要特征进行系统的讨论是必不可少的。本文全面概述了灵活性应用的 DMES 建模和表征。引入了“多能源节点”的概念，以在多能源情况下扩展用于电气灵活性的功率节点模型。给出了 DMES 灵活性的一般定义，以及一般的数学和图形建模框架，基于多维地图，制定了描述单个 MES 和聚合 DMES 的操作特性，包括多能源网络在启用或限制灵活性方面的作用。最后介绍了几个教程示例，并附有关于当前和未来 DMES 实际应用的说明性案例研究。