由於風能具有多變的特性，在現代的電力系統運轉上通常面臨兩項議題，其即包含要求可靠的電力系統保護，同時亦期望獲取更多風能。過電流保護是電力系統保護之重要課題，故障電流及設備之湧入電流均可能導致過電流之產生，其對於供電品質有極大影響，而藉由適當保護設計，即可避免電力系統不必要的跳脫，以提高供電品質。另一方面，為了獲取更多風能，風力發電機與風場特性則應適當匹配。故本論文即致力於研究加強電力系統過電流保謢，同時深入討論風場特性與風力發電機之適切性。
在電力公司進行故障電流研究時，為使電力系統獲得更可靠之保護，對於電力系統接地是否確為有效接地，至為重要。然而傳統的有效接地準則並無考慮接地故障電流可能大於三相短路故障電流的問題，致使某些隱藏性故障可能被忽略。本論文所提之新型有效接地方法將有助於改善傳統準則之缺點，必要之維修改善措施亦可及早進行。此外本論文亦提出以小波轉換為基礎之特徵擷取演算法，將其應用於輔助辨識變壓器湧入電流及故障電流，藉由小波轉換輔助擷取電流波形的特徵，湧入電流辨識效能可獲得提升。
另就攫取風能研究議題，本論文提出一模組化的風力發電機容量因數計算法，其有別於傳統假設的功率曲線計算，主以風力發電機製造商的功率曲線為基礎，不僅運用上較具有彈性，且依據風力發電機原廠資料處理兼顧實務考量，而經由台灣風場之實際風速資料試驗，亦已證明本論文所提方法之有效性。另一方面，考慮風場中風力發電機之風能密度與容量因數情形下，本論文亦提出一新方法可確保風場特性與風力發電機性能之適合度。其中本方法並推導若以風力發電機之額定風速為變數，則當風力發電機非額定操作區之容量因數與額定操作區之容量因數相等時，其所對應之額定風速將為最佳額定風速。同時，本論文亦提出可量化適合度的函數，可提供百分比量度的適合度指標，藉由電力公司所提供的資料，本論文所提方法已應用於評估商用風力發電機及台灣的風場，評估結果應有助於風力發電規劃之研究。

With the wind energy variability, the operation of a modern power system often encounters two issues that include reliable power system protection and sufficient wind energy. To reach reliable operation requirement, overcurrent protection is the first issue to investigate. It is known that the overcurrents in power systems mainly consist of fault and inrush currents, which have significant influences on the reliability of supplying power. However, the maloperation caused by needless trips can be avoided with the proper designing of power system protection. On the other hand, to capture more energy from wind, the characteristics of the wind turbine and the wind farm should be properly matched. This motivated the research of overcurrent protection enhancement and site-matching of wind turbine generators in this dissertation.
To obtain more reliable protection of power system, inspection of effective grounding is usually an important task. Traditional approaches often investigate whether the magnitudes of unbalanced ground-fault currents are higher than that of three-phase fault, yet some hidden failure may be ignored. The method proposed in this dissertation is a beneficial aid to improve the inspection performance. Several necessary actions for power system maintenance can be accordingly performed. Moreover, a wavelet-based approach aided with feature extraction was applied to discriminate the inrush current from internal fault in transformers. By grasping the distinctive behaviors of current waveforms via wavelet-based feature extraction, the recognition of inrush current of transformers can be significantly enhanced.
As for the second part of this dissertation, a modular capacity factor (CF) computation method is proposed that is mainly based on manufacturer's power curves. This proposed method is flexible and data-driven. By using CF computations for wind turbine generators (WTGs) under real wind conditions collected in Taiwan, the method is considered an effective alternative in addition to several existing methods. Meanwhile, a new method to ensure a satisfactory site-matching performance including the wind power density (WPD) and CF considerations has been proposed. The method concludes that the optimum rated speed of a WTG is found to exist when the capacity factors at non-rated and rated operation region are mutually equal. A suitability function is hence suggested to give a per-unit measure of the suitability. By the data acquired from utility, the approach has been applied to assess several wind farms in Taiwan. Experimental results are believed to be beneficial for wind power planning studies.

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