隨著科技文明的進步，全球居住人口比例持續增加，導致土地人口密度上升，地面交通壅塞的問題日益嚴重，因此人們將目光轉向空中的電動飛行載具，並發展了許多航空交通運輸工具。而電動飛機未來將應用於多個領域，然而長途飛行對電動飛機而言是一大挑戰，因此需提升電動飛機馬達的效率和功率密度，以促進電動飛機產業的發展。
本文以高功率密度、高效率為馬達設計目標，考量馬達整體系統的性能，通過六相永磁馬達的設計，提升馬達的容錯率，增加電動飛機飛行過程的安全穩定性，並進行一步提升馬達的功率密度和效率；在材料選擇上，也考慮了功率密度、效率和製程所帶來的影響。
在效率方面，本文考量了驅動器不同切換頻率下，電流對馬達效率的影響，以及馬達本身電感因素的設計，此外，還考慮了直流銅損、交流銅損與PWM載波電流之間的關係，綜合考量驅動器切換頻率、各項損失、效率和功率密度的平衡，以達成一高功率密度、高效率的無人機馬達。最後對馬達進行最佳化，進一步提升馬達效率和功率密度。

With the advancement of technological civilization, the proportion of the global population living in urban areas increase, leading to higher population density and worsening ground traffic congestion. Consequently, people have turned their attention to electric flying vehicles, resulting in the development of various aerial transportation tools. Electric aircraft are expected to be applied in multiple fields in the future. However, long-distance flights pose a significant challenge for electric aircraft, necessitating improvements in the efficiency and power density of their motors to promote the development of the electric aircraft industry.
This paper aims to design a motor with high power density and high efficiency, considering the overall performance of the motor system. By designing a six-phase permanent magnet motor, the fault tolerance of the motor is enhanced, thereby increasing the safety and stability of the electric aircraft during flight. Additionally, efforts are made to further improve the power density and efficiency of the motor. In terms of material selection, the impact of power density, efficiency, and manufacturing processes are also considered.
Regarding efficiency, this paper examines the impact of current on motor efficiency under different switching frequencies of driver and the design of the motor inductance. Furthermore, the relationships between DC copper loss, AC copper loss, and PWM carrier current are considered. A comprehensive balance of driver switching frequency, various loss, efficiency, and power density is achieved to design a high power density, high efficiency motor for drones. Finally, the motor is optimized to further enhance its efficiency and power density.

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