臺灣博碩士論文加值系統

風力發電上可以使用不同類型的發電機，其中包括永磁式同步發電機，磁阻式發電機，磁通切換永磁發電機，高溫超導發電機等等。不同的發電機對於特定應用都具有不同特性。本文總結了各型風力發電機的優點和缺點。此外，本論文亦探討設計風力發電機時主要會考慮到的因素，它們包括效率、頓轉轉矩、轉矩漣波、尺寸和重量以及發電機中會使用到的磁鐵材料。此外，本論文初步設計一部小型永磁式同步風力發電機的雛形，其槽極數分別為32極33槽和32極36槽，其中詳述風力發電機的設計流程以及風力發電機設計時的考慮因素。最後，本文分別使用一次因子法與田口法來優化風機的設計，大幅降低所設計風機的頓轉轉矩。結果顯示，使用田口法可以得到較好性能的風力發電機。

A wind turbine may use different generators including permanent magnet synchronous generator, reluctance generator, flux switching permanent magnet machine, high–temperature superconducting generator and others. Various generators have different characteristics for specific applications. The advantages and weak points for wind generators are summarized in this work. Additionally, this work also investigates the main considerations when designing the wind generator. They include the efficiency, the cogging torque, the torque ripple, the size, the weight and the magnet materials used in machines. Additionally, This thesis has the initial prototype design on small permanent magnet synchronous generator. The slot number and pole number is 32 pole 33 slot and 32 pole 36 slot, respectively. The design steps and the design considerations of the wind generator are also discuessed. Finally, this work uses one-factor-at-atime method and Taguchi’s Orthogonal Arrays Method to improve the performance of the wind generator to reduce the cogging torque of the machine. The results show that we can obtain better performance wind generator by using Taguchi’s Orthogonal Arrays Method.

ACKNOWLEDGMENTS i
中文摘要 ii
ABSTRACT iii
TABLE OF CONTENTS iv
LIST OF FIGURES vii
LIST OF TABLES ix
LIST OF SYMBOLS x
I. INTRODUCTION 1
1.1 Background and Motivation 1
1.2 Literature Review 2
1.3 Contribution of This Thesis 4
1.4 Organization of Thesis 5
II. MAGNET MATERIALS OF WIND GENERATOR 6
2.1 Ferrite 6
2.2 AlNiCo 6
2.3 Rare earth 6
III. TYPES OF WIND GENERATOR 7
3.1 Fix speed wind generator 7
3.2 Variable speed wind generator 7
3.2.1 PM-based wind generators 8
3.2.2 Reluctance-based wind generators 10
3.2.3 Switching-based wind generators 12
3.2.4 Superconductor-based wind generators 13
3.3 Comparison of different wind generator characteristic 14
IV. IMPROVED METHODS FOR WIND GENERATOR 16
4.1 Efficiency 16
4.2 Cogging torque 17
4.3 Reliability 18
4.4 Cost 19
4.5 Output power 20
4.6 Torque ripple 20
4.7 Corrosion 21
V. WIND GENERATOR DESIGN PROCEDURE 22
5.1 Design methodology and consideration 22
5.1.1 Selection for the slot and pole number 25
5.1.2 Loss 26
5.1.3 Efficiency 27
5.1.4 Cogging torque 27
5.2 Material choosing 28
5.2.1 Permanent magnet 28
5.2.2 Silicon steel 29
5.3 Geometric parameters 30
5.3.1 Sizing 32
5.3.2 Induced voltage 32
5.3.3 Magnet thickness 32
5.3.4 Flux density 32
5.3.5 Flux per pole 33
5.3.6 Tooth width 33
5.3.7 Stator yoke width 33
5.3.8 Rotor yoke width 33
5.3.9 Rotor outer radius 34
5.3.10 Slot open 34
5.3.11 Slot fill factor 34
5.3.12 Current density 34
5.4 Winding design 35
5.5 Optimization analysis 43
5.5.1 Sensitivity Analysis 44
5.5.2 Taguchi’s Orthogonal Arrays Method 44
5.6 Analysis tool 47
5.6.1 Analysis method 47
5.6.2 Analysis tool 48
VI. SIMULATION RESULTS 49
6.1 Wind generator prototype design 49
6.1.1 Different Pole-slot numbers and generator structure 49
6.1.2 Wind generator prototype design 53
6.2 Optimization analysis 63
6.2.1 Results obtain by the Sensitivity Analysis 64
6.2.2 Results obtain by the Taguchi’s Orthogonal Arrays Method 69
Ⅶ. COLCLUSIONS AND FUTURE WORKS 79
7.1 Conclusions 79
7.2 Future works 80
REFERENCES 81

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