近年來國內對太空相關研發技術愈來愈重視，但對於衛星相關組件之研發技術仍尚未成熟，因此關鍵零組件之開發更是各研究單位之研發重點。而其中反應輪(Reaction Wheel)為衛星姿態控制的關鍵組件，利用轉動物件角動量守恆的物理特性，透過控制器改變反應輪之運轉速度，使轉動物件之角動量產生變化，獲得扭力輸出，以改變衛星的姿態。
本文針對適用於反應輪之無槽式軸向馬達以及無槽式外轉子徑向馬達進行慣量分析，設計出在符合目標轉矩下，每單位可提供較大角動量之馬達。首先推導軸向馬達設計所需之參數，並藉由電磁模擬驗證其正確性，以及探討無槽式馬達之繞組對馬達影響，並改善其缺點。再來將軸向馬達以及徑向馬達在同樣的空間限制以及皆可達到目標之電磁性能下，針對其轉動物件進行轉動慣量之分析。接著從獲得之馬達規格透過電磁模擬分析其損失來源及比例，在不影響輸出性能下，使其效率最佳化。
最後得一高慣量密度，且高效率之反應輪馬達設計。

In recent years, domestic space-related R&D technology has become more and more important while the research and development technology for satellite-related components has been still not mature. Hence, the development of key components has become the focus of the research and development in each research unit. The reaction wheel is one of the key components in terms of satellite attitude control. Using the physical characteristics of the angular momentum conservation of the rotating object and changing operating speed of the reaction wheel by the controller may change the angular momentum of the rotating object to obtain the output torque to change the attitude of the satellite.
In this thesis, the inertia analysis is carried out for the slotless axial permanent magnet synchronous motor and the slotless outer rotor radial motor which are suitable for the reaction wheel. The motor is designed to provide a large angular momentum per unit under the target torque. First, the parameters required for the design of the axial motor are derived, the correctness is verified by electromagnetic simulation, the influence of the winding of the slotless motor on the motor is discussed, and the shortcomings are improved. Then, the axial motor and the radial motor are analyzed for the moment of inertia of the rotating object under the same space limitation and the electromagnetic properties of the target. From the obtained motor specifications, the source and proportion of the loss are analyzed through electromagnetic simulation, and the efficiency is optimized without affecting the output performance.
Finally, a high inertia density and high efficiency reaction wheel motor design is obtained.

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