In recent years, combined-cycle units (CCUs) have been operated as providers of flexibility to facilitate increasing shares of renewables. Consequently, optimization models have been proposed to determine the configuration of CCUs. However, most of the existing models assume that any transition between configurations finishes in a single interval. This assumption is often violated in reality, as a transition might last up to a few hours during which the CCU has limited dispatchability. In this paper, we propose a mixed-integer programming formulation that represents the transition ramping of CCUs. We show the tightness and compactness of the proposed model. Numerical studies are performed on an illustrative test system and a MISO system.

中文翻译：

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联合循环机组过渡斜坡的严密制定

近年来，联合循环机组 (CCU) 一直作为灵活性的提供者运营，以促进增加可再生能源的份额。因此，已经提出了优化模型来确定 CCU 的配置。但是，大多数现有模型假设配置之间的任何转换都在单个间隔内完成。这个假设在现实中经常被违反，因为转换可能持续长达几个小时，在此期间 CCU 的可调度性有限。在本文中，我们提出了一个混合整数编程公式，它代表了 CCU 的过渡斜坡。我们展示了所提出模型的紧密性和紧凑性。数值研究是在说明性测试系统和 MISO 系统上进行的。