磁制動器具有非接觸、低磨耗及低噪音等特性，適合應用於需長時間運轉之旋轉系統。然而，固定構型磁制動器之制動扭矩受轉速與幾何配置限制，且磁石與導體間不可避免之氣隙易造成磁通發散與洩漏，使其難以在有限尺寸與調節行程下兼具高制動性能與自動調節能力。因此，本研究提出具軸向作動自調節之徑向磁通磁制動器，並於鋁導體內嵌入軟磁性導磁塊，以提升磁通利用率及調節過程之制動性能。
本研究以垂直軸風力發電機之運轉資料作為工程設計案例，將操作需求映射為磁制動器端 355–492 RPM 之轉速範圍。首先建立包含永久磁石、氣隙、導體、導磁塊及背鐵之等效磁路與解析扭矩模型，並分析磁石規格、導體厚度、導磁塊數量、展開角度及軸向位置之影響。最終採用厚度 3 mm 之 Al1060 導體、32 個展開角度 2°之 S20C 導磁塊，軸向調節範圍為 −12.5 至 −2.7 mm。自調節機構利用質量塊產生之離心力，經 45°斜面轉換為軸向推力，並配合彈簧回復力，使導體位置及有效感應面積隨轉速自動改變。其後以三維有限元素分析驗證解析模型，並製作實體樣機進行導體效益及被動調節實驗。
實驗結果顯示，具導磁塊構型於 355–492 RPM 之調節過程中，平均制動扭矩由 2.26 Nm 穩定增加至 5.19 Nm，各操作點標準差介於 0.03–0.08 Nm。於 492 RPM、−2.7 mm 之最大設計操作點，具導磁塊與一般導體構型之實驗扭矩分別為 5.19 Nm 與 1.68 Nm，制動扭矩提升約 208.9%。被動調節實驗亦證實，導體可隨轉速上升產生軸向位移，並於轉速下降時藉由彈簧復歸，驗證無外部電力控制下之自調節作動可行性。綜合而言，本研究所提出之具導磁塊導體設計可於有限調節行程內改善磁通導引、提升制動性能與輸出穩定性，並結合離心式被動調節機構實現隨轉速變化之制動調節。

This study proposes a radial-flux self-regulating magnetic brake with axial conductor adjustment and soft-magnetic inserts embedded in an aluminum conductor. The inserts provide additional low-reluctance flux paths to improve magnetic-flux utilization and braking performance within a limited adjustment stroke. A vertical-axis wind-turbine operating condition was adopted as an engineering design case, corresponding to a magnetic-brake shaft speed range of 355–492 RPM. An equivalent magnetic-circuit model, an analytical eddy-current torque model, three-dimensional finite element analysis, and prototype experiments were integrated to evaluate the proposed design. Experimental results demonstrated that the optimized conductor increased braking torque from 2.26 Nm at 355 RPM to 5.19 Nm at 492 RPM. At the maximum design operating point, its braking torque was approximately 208.9% higher than that of the conventional conductor. The centrifugal self-regulating mechanism also successfully produced speed-dependent axial displacement without external electrical control.

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