本論文在IEEE第二標準模型第一系統基礎上提出在串聯補償之傳輸線路中再串聯一個靜態同步串聯補償器來抑制發電廠機械轉軸可能發生的次同步共振現象。整個系統模型在三相平衡條件下建立至d-q同步參考軸,爲了獲取靜態同步串聯補償器在阻止次同步現象之更好效果，本文利用模態控制理論之極點安置法設計一個參數恰當的輔助阻尼控制器。在穩態分析中，不同工作條件下對比不採用靜態同步串聯補償器之系統與採用靜態同步串聯補償器及其輔助控制器之系統特徵值，本論文所提出的靜態同步串聯補償器在抑制次同步共振方面確有成效。進一步在動態分析中，同樣對比這兩種系統，模擬結果證實所提出的靜態同步串聯補償器架構確有功效，因為次同步共振現象之動態波形非常密集，文中利用快速傅立葉變換把時域數據轉到頻域，各次同步頻率即被驗證。最後，文中還對系統做了不同工作條件下的動態模擬，來進一步測試所提出的設計。

This thesis presents the damping of subsynchronous resonance (SSR) of the IEEE Second Benchmark Model, System #1 using a static synchronous series compensator (SSSC). The integrated system mathematical model is expressed in d-q reference frame under three-phase balanced condition. To achieve better damping performance on damping SSR of the studied system, a proper oscillation damping controller (ODC) is designed by using pole-assignment approach based on modal control theory. Steady-state analysis under different operating conditions is performed to verify the effectiveness of the SSSC joined with the designed ODC using eigenvalue analysis. Comparative time-domain simulations between the system without and with the proposed SSSC joined with the ODC reveals that the proposed SSSC with the designed ODC can suppress SSR of the studied system effectively. It can be concluded from the simulation results that the proposed SSSC coordinated with the designed ODC can significantly damp SSR under various operating conditions.

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