本論文首先提出以雙饋式感應發電機為基礎之聚集等效離岸式風場，經由電壓源轉換器為基礎之高壓直流傳輸系統連接至電網，形成一個單饋入式高壓直流傳輸系統，藉由穩態與動暫態之模擬，分析該系統分別連接至強、弱電網之穩定度特性。本論文再將單饋入式高壓直流傳輸系統擴展為多饋入式高壓直流傳輸系統，並比較多饋入式高壓直流傳輸系統對系統穩定度之改善特性。在穩態特性方面，本論文分析了不同風速、不同連接傳輸線長度對系統穩定度之影響，在動態模擬方面完成實際風速之模擬，在暫態部分完成匯流排電壓驟降與電網端電壓三相短路故障之模擬。由模擬結果分析得知，不同匯流排間傳輸線長度以及特性，皆會影響系統穩定度，並且當單饋入式系統連接至弱電網，若發生嚴重故障時，系統響應將會出現不穩定之發散特性。

This thesis first proposes an equivalent aggregated offshore wind farm based on doubly-fed induction generator fed to a power grid through a single-infeed high-voltage direct-current transmission system (SI-HVDC) based on voltage-source converter. Through steady-state, dynamic, and transient simulations, the characteristics of the SI-HVDC connected to strong and weak grids are performed. This thesis then extends the SI-HVDC to be multi-infeed high-voltage direct-current transmission systems (MI-HVDC) to compare the characteristic improvement of using the MI-HVDC. Steady-state characteristics of the studied systems under different wind speeds as well as distinct lengths and types of tie lines are achieved. Dynamic and transient simulations of the studied systems subject to a wind-speed disturbance, a three-phase fault at the power grid, and the bus-voltage sag are also carried out. According to the simulation results of the studied systems, the length and type of the tie lines between different buses will affect the stability of the studied systems while the responses of the the studied SI-HVDC connected to a weak grid subject to a severe fault can be unstable with divergence.

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