永磁渦電流制動器具有非接觸制動與低磨耗等特性，但固定幾何參數構型之扭矩–轉速特性受既定磁路與幾何參數限制，難以於運轉過程中依需求調整制動輸出。本研究以直立式軸向自調節徑向磁通渦電流制動器為研究對象，透過離心質量塊、斜坡滑槽與彈簧驅動導體盤軸向位移，在維持徑向氣隙固定之條件下，藉由改變有效軸向重疊長度La調整制動扭矩。研究由目標制動需求出發，以磁等效電路解析模型進行參數篩選，並透過三維有限元素分析取得制動扭矩與軸向電磁力，據以決定機構作動範圍與行程。自調節機構則建立考量離心力、重力、彈簧回復力、接觸摩擦及軸向電磁力之準靜態力學模型，分析升、降速受力差異，並以所需彈簧力差異及回程特徵轉速偏差為雙目標進行參數最佳化，完成磁制動端與自調節機構之耦合設計。
依400 rpm、1.0 N·m與800 rpm、2.5 N·m之設計工況，選定La=18–22 mm為主要作動範圍，對應 4.0 mm 軸向行程；兩設計點之有限元素制動扭矩與目標值分別相差 2.8 % 與 1.2%。固定Lₐ實驗與有限元素分析呈現一致之扭矩變化趨勢。自調節升速實驗中，400 rpm與800 rpm之制動扭矩分別為1.13 N·m與2.68 N·m，較目標值高出12.6%與7.0%；800 rpm 時軸向位移達3.82 mm，為設計行程之95.4%，顯示原型可隨轉速改變有效軸向重疊長度，進而調整制動扭矩。
降速實驗則出現回程延遲與停機後殘留位移。將實際彈簧預壓條件及方向相依之等效摩擦參數納入準靜態模型後，可改善降速路徑預測，但仍無法完整描述低轉速回程行為。本研究建立由目標制動需求出發，結合軸向電磁力、直立式機構受力分析與多目標最佳化之整合設計流程，並透過原型實驗驗證自調節構型之可行性，同時指出準靜態模型之預測限制。

Permanent magnet eddy current brakes (PMECBs) provide non-contact braking with reduced wear, but fixed-parameter configurations have limited torque adjustment capability. This study presents a vertically oriented, axially self-adjusting radial-flux eddy current brake. Centrifugal masses, ramp slots, and springs drive axial conductor displacement, varying the effective overlap length while maintaining a fixed radial air gap. A magnetic equivalent circuit (MEC) model was used for parameter selection, followed by three-dimensional finite element analysis (FEA) to calculate braking torque and axial electromagnetic force. A quasi-static mechanical model accounting for centrifugal force, gravity, spring force, electromagnetic force, and contact friction was developed for multi-objective optimization.
For target torques of 1.0 N·m at 400 rpm and 2.5 N·m at 800 rpm, an effective axial overlap range of 18–22 mm was selected, requiring a 4 mm stroke. The FEA torque deviations from the targets were 2.8% and 1.2%. Prototype experiments yielded 1.13 and 2.68 N·m, respectively, with a displacement of 3.82 mm at 800 rpm, reaching 95.4% of the designed stroke. Delayed return and residual displacement were observed during deceleration. Revising the spring preload and equivalent friction parameters improved displacement predictions but did not fully reproduce the return behavior. The results demonstrate the feasibility of the proposed design and identify limitations of the quasi-static model.

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