著者

小島 千昭 平田 真人 津村 幸治

出版者

自動制御連合講演会

雑誌

自動制御連合講演会講演論文集 第57回自動制御連合講演会

巻号頁・発行日

pp.1927-1934, 2014 (Released:2016-03-02)

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Swing instability is an undesirable emergent phenomenon of a power network, in which generators coherently lose synchronism after an unexpected injection of a disturbance. In this paper, we analyze a mechanism of this phenomenon for a power network where subsystems with multiple identical generators are hierarchically interconnected. We first decompose the dynamics of each subsystem into oscillatory and zero eigenvalue modes by mode decomposition. As we see that the zero eigenvalue modes govern an unstable behavior, we define the transient stability margin in terms of the modes. As a main result, we clarify the energy transfer to the zero eigenvalue modes by using the stability margin, the collective dynamics of the entire system and the strength of the connection between subsystems. Based on this characterization, we predict that this energy transfer to the zero eigenvalue mode increases when a phenomenon of the swing instability emerges and confirm this prediction by using numerical simulation. A contribution of this paper is that we clarify an emergent energy transfer from a control theoretic view point.