考量空間限制及噪音之影響,小型風力發電系統為較適用於一般住宅或其他應用場合之再生能源系統。然而,為降低製造成本,一般的小型風力發電系統通常由二極體整流器串接一直/直流電源轉換器做最大功率追蹤,因此,在發電機側將會產生嚴重的電流諧波失真,不僅會降低發電效率亦會對風力發電機造成額外的機械應力及產生多餘的噪音。本論文主要目的即在於研發一新型單級式交直流轉換器,降低整體系統電流諧波及噪音,並提高系統的轉換效率。 基本上,本論文的主要貢獻可摘要如下:首先,提出一新型交直流轉換器作為風力發電系統之介面,此轉換器僅需三個主動開關,在電路操作時為同時導通及同時截止並操作在不連續電流導通模式下以減低電流總諧波失真。此外,儲存在漏電感上之能量可被回收且主動開關上之電壓應力可減低約50%。接著針對本論文提出之新型交直流轉換器,說明其操作狀態與工作原理,以及進一步推導出直流模型與分析此轉換器之穩態特性。最後實體製作一額定200W之新型交直流轉換器之雛形,並實體建構一測試平台用以驗證所提轉換器之可行性與效能。經由實測結果顯示,發電機側之電流總諧波失真可降低至5%以下,其電源轉換效率於20W至200W的負載情況下介於90%至92%。
Due to the limited space and noise considerations, a small-scale vertical wind power generation system (WPGS) is rather suitable for residential or other applications. However, for low cost purpose, it usually consists of a three-phase diode bridge cascading another DC converter for maximum power tracking control. Hence, the generator currents will contain harmonics which will result in additional mechanical stress, noise and losses. Therefore, the objective of this thesis is aiming at developing a novel single stage three-phase AC/DC converter to reduce the harmonics and noise as well as enhancing the efficiency. Basically, the major contributions of this thesis may be summarized as follows. First, a novel single-stage three-phase AC/DC converter is proposed for the small scale WPGS. This new topology requires only three active switches with common source terminal and are turned on/off simultaneously under discontinuous conduction mode to reduce the current THD. Besides, the stored energy of the leakage inductance can be recovered and the voltage stresses of the active switches are reduced by about 50%. Second, the corresponding mathematical model is derived for steady state characteristic analysis and parameter determination for converter design. Finally, a 200W prototype is implemented for verifying the validity of the proposed converter. It is seen that the resulting generator current THD can be reduced to below 5% and the efficiency is between 90% and 92% when the load is from 20W to 200W.
為了持續優化網站功能與使用者體驗,本網站將Cookies分析技術用於網站營運、分析和個人化服務之目的。
若您繼續瀏覽本網站,即表示您同意本網站使用Cookies。