風力發電是世界上發展最快的再生能源之一，隨著風力發電占電力系統的比例越來越高，高占比再生能源的系統將會產生頻率穩定度的問題。一般而言風力發電皆採取最大功率追蹤型態以追求最大效率。但考量到系統穩定度及系統功率調度，風機的設定點控制模態也逐漸備受矚目，在設定點控制模態下風機可以保存備轉容量以便協助系統調頻。風機在設定點控制模態下可以進行慣性釋放調頻以及速度垂降調頻，然而該採取何種控制策略使風機進行適當的調頻是一個難題。本研究主要探討風機的慣性控制，利用Matlab/Simulink模擬軟體進行分析，提出在設定點控制模態下調頻效果良好、且兼顧風機轉速安全性的控制策略。另外，許多文獻所提的慣性控制皆操作在設定點控制模態，也就是在保有備轉容量之情況下進行慣性釋放。然而實際上多數風機皆是運轉在最大功率追蹤模態之下，因此本研究也將提出風機運轉在最大功率追蹤時該如何進行慣性釋放。不論風機是採取設定點控制或是最大功率追蹤控制皆能進行慣性釋放，以強化風機的調頻性能。透過模擬結果證實本研究提出之控制策略確實有效地增強風機的調頻能力。

Wind power is one of the fastest growing renewable energy resources in the world. The penetration of the wind generation into the power system is substantially increasing. Compared to the system with low renewable penetration, systems with high proportion of renewable energy usually encounter frequency stability problem. Wind turbine generally operates at maximum power point tracking (MPPT) mode for maximizing wind power production, with less assistance to the frequency support. To be able to provide frequency support, the deloaded operation of the wind turbine has been gradually attracting more attention. Since the set-point control reserves the capacity to give the inertial and speed droop responses, the set-point control becomes an optimization problem. Except the deloaded mode operation, this thesis also discusses the possibility of releasing the inertial energy under the MPPT mode operation, while stability of the wind turbine is still maintained. The relevant research works were conducted using the Matlab/Simulink simulation software, taking both frequency regulation and rotor stability into account. Simulation case studies demonstrate the effectiveness of the proposed control strategies to enhance the frequency regulation capability of wind turbines.

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