Halbach磁環具有極佳的磁通分布，本論文探討Halbach磁環於永磁無刷馬達設計之應用，在不改變馬達幾何結構的前提下，使具有較低之頓轉扭矩，且反電動勢常數與磁交鏈在位置變化上呈現弦波式分佈，該特性易於增加永磁無刷馬達的伺服性能。
本論文提出一套最佳化方法的馬達設計流程，以一個Halbach磁環的三相八極九槽永磁無刷馬達為設計應用例，利用遺傳演算法先求具最佳效率馬達合適的結構尺寸，接著分別以有限元素法分析與等效磁網路分析法模擬馬達最大磁通密度，最後再進行馬達電氣參數的設計。
另外，由於磁鐵磁化型態的不同會影響馬達的特性，本論文亦探討在相同結構尺寸與電氣下，進一步改變馬達的轉子磁鐵設計為常見的平行磁化與徑向磁化兩種不同的型態，並分別利用有限元素分析軟體，模擬分析三種不同磁化型態之永磁無刷馬達，其在磁場與輸出特性上的差異性。

In this thesis, Halbach cylinders are applied to the design of permanent magnet brushless motors. The use of Halbach cylinders is able to improve motor characteristics such as low cogging torque and sinusoidal back-EMF, due to the excellent flux distribution. Therefore, the output performance of the permanent magnet servomotor with the Halbach cylinder design can be significantly improved without recourse to the motor structure.
This thesis mainly presents an optimal motor design procedure based on the genetic algorithm. For a Halbach magnet brushless motor of 3 phases, 8 poles and 9 slots, the genetic algorithm is first employed to determine the motor dimensions to achieve for the highest efficiency fitness. Both of the finite element analysis and the magnetic network analysis are then used respectively to calculate the air gap flux density and the related motor electrical parameters. Due to considering the possible effects of different magnetized magnets on motor characteristics, two commonly used types of rotors which are with parallel and radial magnetization are also studied under the same geometry dimensions and electrical parameters. Finally, the flux density and motor output performance resulting from these three models are compared using the finite element analysis method.

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