本論文的研究重點在於分析渦電流現象對於磁性聯軸器傳動特性之影響。因為磁性聯軸器內部之隔離筒為導電性材料，當磁性聯軸器運轉時會造成磁性聯軸器內部隔離筒切割永久磁鐵所產生之磁場，由於隔離筒的導電特性，會感應出渦電渦於隔離筒內，此感應渦電流會產生與磁性聯軸器運轉方向相反的勞侖茲力(阻尼力或制動力)與反向扭矩(阻尼扭矩)。磁性聯軸器之磁場來源為永久磁鐵，所產生之磁場是固定的，當我們設計選用磁性聯軸器做為動力傳輸時，考慮其所能傳遞之最大扭矩時，必須將感應渦電流現象所造成之阻尼效應考慮進去，避免發生扭矩不足，造成磁性聯軸器之傳動誤差。在論文中除了推導感應渦電流之統御方程式計算出感應渦電流外，還利用電磁模擬分析軟體ANSOFT進行模擬比較其正確性。

This thesis analyzes the effects of the eddy current phenomenon on transmission characteristics of a magnetic coupling. The stainless steel made hollow cylinder installed between the inner and outer magnetic couplings cuts the magnetic field produced by the permanent magnets of the magnetic coupling. This will induce eddy current in the cylinder as the magnetic coupling rotates. The induced eddy current produces Lorentz force (a form of damping force or braking force) that is opposite to the rotating direction of the magnetic coupling and also produces damping torque. Since the permanent magnets are the source of magnetic field of the magnetic coupling, it produces a steady magnetic field. In order to prevent from the lack of torque that can cause the transmission inaccuracy when choosing magnetic couplings as precision transmission devices, the damping force caused by eddy current should be taken into consideration. This thesis contains not only the calculation of the induced eddy current by the governing equation but also uses the simulated software "ANSOFT" to compare its accuracy

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