本論文係分析波浪能驅動之感應發電機與市電系統併聯運轉時，在電網及感應發電機系統上之穩態及動態特性等影響。在本論文中，單機系統係分別以一台威爾斯渦輪機驅動感應發電機直接併聯電網以及經由電力電子轉換器併聯電網之架構做為研究模型。本論文在三相平衡系統下採用交直軸等效電路模型，分別建立威爾斯渦輪機、感應發電機、整流-換流模組、傳輸線、負載、市電等之模型，推導其數學模型來完成整體動態方程式，並利用特徵值來分析系統之動態穩定度。在穩態方面，本論文則分別探討威爾斯渦輪機軸向之氣流速度、葉片長度、電網端電壓等量對系統特性之影響。在動態研究方面，則考慮系統發生干擾或故障時，可能對波浪能發電系統造成的影響做成評估及分析。本論文最後分析等效大容量之波浪能發電機組併入實際系統後對系統之衝擊。

This thesis analyzes both dynamics and steady-state performances of a wave-energy generation system. Both direct grid-connected wave-energy induction generator (WEIG) and WEIG connected to the grid through power-electronic converters (PECs) are employed as the studied system models. A d-q axis equivalent-circuit model is employed to establish the Wells turbine, induction generator, PECs, transmission lines, loads, and grid to derive the complete dynamic equations of the studied system under three-phase balanced loading conditions. Both eigenvalue and nonlinear-model simulations are employed to determine the dynamic stability of the studied system. The axial velocity of air, blade length, and grid voltage of the studied system under steady-state conditions are also examined. Dynamic characteristics of the studied WEIG subject to disturbance and faulted conditions are explored. Finally, system impacts of an equivalent large capacity WEIG connected to an actual power system are explored.

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