本論文旨在探討多種再生能源場透過以模組化多階轉換器為基礎之多端高壓直流鏈連接至多機電力系統之穩定度分析。所建構之微電網包含浮動式離岸風場、固定式基座離岸風場與海洋溫差發電系統，分別經由多端高壓直流鏈連接至含有四部同步發電機之多機電力系統。本論文研究首先針對系統在不同工作條件下進行小訊號穩定度分析，進而根據系統中之低頻振盪模態設計模組化多階轉換器之輔助阻尼控制器，並透過頻域分析方法驗證其參數配置之合理性。本論文最後進行動態與暫態時域模擬，以評估控制器在各種擾動情境下之控制效能。由模擬結果顯示，本論文所設計之控制器可抑制系統振盪、提升穩定度與響應品質。

This thesis conducts a stability analysis of integrating various renewable energy sources into a multimachine power system (MMPS) via a multi-terminal high-voltage direct-current (MTDC) link based on a modular multilevel converter (MMC). The constructed microgrid consists of a floating offshore wind farm (FOWF), a fixed-bottom (FBOWF), and an ocean thermal energy conversion (OTEC) system, each connected to the MMPS comprising four synchronous generators through the MTDC link. The study first performs small-signal stability analysis under various operating conditions. Based on the identified low-frequency oscillation modes, a supplementary damping controller (SDC) for the MMC is designed, and its parameter configuration is verified through frequency-domain analysis. Finally, dynamic and transient time-domain simulations are conducted to evaluate the SDC’s performance under various disturbance scenarios. Simulation results demonstrate that the proposed SDC can suppress system oscillations and enhance both stability and response quality.

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