此論文介紹一種具有Z方向磁通量的磁齒輪減速電動機的設計步驟，應用於輔助年長者起立與坐下。該電機為雙轉子結構，兩個旋轉方向相反的轉子皆有著Z方向的永磁，通過鐵軛產生磁耦合。藉由等效磁路模型計算電機的輸出轉矩和齒輪組的扭力矩，在應用尺寸的限制下找到該輸出轉矩與扭矩的交點來選取初始設計尺寸，接著使用三維有限元分析來驗證該初始設計，並在不同操作條件下做模擬測試，相應地進行修改，找出最佳尺寸。

The design procedure for a magnetic geared motor with axial flux to assist the sit-to-stand motion of elderly adults is presented in this paper. The machine uses two rotors rotating in opposite directions, and each consists on axially magnetized permanent magnets and are magnetically coupled through an iron yoke. The magnetic equivalent circuit modelling is used to calculate both the output torque of the motor set and the pull-put torque of the gear set. The dimensions for an initial design was determined by finding the intersection of these torques within the size constraint of the application. A 3-dimensional finite element analysis was used to validate this initial design and machines with similar dimensions were compared according to their pull-out torque and maximum load torque supported. The final design was tested under the simulated load conditions for a standing-up motion and proved capable of aiding a person in standing up.

THESIS VALIDATION LETTERS ................................................... i
ACKNOWLEDGEMENT .............................................................. iii
摘 要 ........................................................................................... iv
ABSTRACT ................................................................................... v
TABLE OF CONTENTS ............................................................... vi
LIST OF FIGURES ..................................................................... viii
LIST OF TABLES .......................................................................... x
LIST OF SYMBOLS ..................................................................... xi
CHAPTER 1 INTRODUCTION .................................................... 1
1.1 Background ............................................................................. 1
1.2 Objectives ............................................................................... 2
1.3 Literature review ..................................................................... 2
1.4 Magnetic gears ....................................................................... 4
1.5 Thesis outline ......................................................................... 7
CHAPTER 2 DEVICE DESCRIPTION AND MOTOR SET ......... 8
2.1 The axial-flux magnetic-geared motor ................................... 8
2.2 Physical dimensions and input circuit .................................... 9
2.3 Output torque calculation ..................................................... 11
2.4 Output torque for multiple dimensions ................................. 16
CHAPTER 3 GEAR SET ........................................................... 21
3.1 Dimensions .......................................................................... 21
3.2 Pull-out torque calculation ................................................... 21
3.3 Case 1: Fixed HPM and rotating LPM ................................. 24
3.4 Case 2: Fixed LPM and rotating HPM ................................. 28
3.5 Torque ratio .......................................................................... 30
3.6 Pull-out torque for multiple dimensions ................................ 31
CHAPTER 4 SYSTEM SETUP AND VALIDATION .................. 34
4.1 Assembly considerations ..................................................... 34
4.2 Curves intersection .............................................................. 34
4.3 Numerical validation ............................................................ 36
4.4 Magnetic saturation in iron parts ......................................... 36
4.5 Pull-out torques ................................................................... 41
4.6 Maximum constant load simulation...................................... 44
4.7 Standing-up load simulation ................................................ 47
CHAPTER 6 CONCLUSIONS AND RECOMMENDATIONS ... 50
REFERENCES .......................................................................... 52

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