近年太空產業蓬勃發展，國內外對其相關組件的研發與改良亦隨之興起。反應輪(Reaction Wheel)作為衛星姿態控制的關鍵組件，其原理為利用慣量守恆之物理特性，藉由改變反應輪轉子運轉速度，使角動量改變，藉此產生扭力以調整衛星姿態。然而，受限於現有滾珠軸承之摩擦損失，反應輪的體積與功耗表現進步緩慢，若能消除摩擦損失，則可進一步提升反應輪旋轉速度，並以較小轉子體積獲得相同轉動慣量。
　　本文以一新型混合式磁性軸承為對象，利用全橋式直流-交流電源轉換器作為驅動電路，輔以位置-電流雙閉迴路控制法對此系統進行控制，目標使反應輪之轉子摩擦功耗大幅度下降，從而提升轉速。本文將基於此新型混合式磁性軸承系統建立數學模型，並使用MATLAB Simulink電路模擬軟體搭配控制架構，驗證其可行性，最終完成磁性軸承驅動電路，與配備有磁性軸承之反應輪進行整合測試，並與模擬結果交互驗證。

The space industry has grown rapidly in recent years. To catch up with such trend, the research and development on the satellite and its payloads have also emerged. As reaction wheels are key components of the attitude and orbit control system in satellites, its principle is based on conservation of angular momentum. When the rotational speed of a reaction wheel changes, the angular momentum of the satellite should remain the same and thereby torque is generated to adjust the satellite attitude. However, the performance of a reaction wheel is often limited by the friction of the ball bearings. When ball bearings can be replaced with magnetic bearings, the friction loss can be reduced to zero. Thus, the rotational speed of rotor can be increased. The volume and mass of a reaction wheel is reduced as well.
　　In this thesis, a novel hybrid magnetic bearing applied to reaction wheel has been adopted. The full-bridge DC-AC inverter is used as the driving circuit, and the system is controlled by the displacement and the current closed-loop control method. The purpose of this control system is to reduce friction loss and increase the rotational speed of a reaction wheel. This thesis also derives the mathematical model of the magnetic bearing system, using MATLAB Simulink to verify its feasibility. Finally, a driver is made to do the real test where the possibility of applying a magnetic bearing system to a reaction wheel is demonstrated.

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