軸向磁力軸承最佳化設計與驗證

Design Optimization and Experimental Verification of an Axial Magnetic Bearing

張景翔(Jing-Siang Jhang)

指導教授 ： 楊勝明

國立臺北科技大學/電資學院/電機工程系研究所/碩士(2010年)

摘要

轉子磁懸浮系統通常需要徑向與軸向磁力使轉子懸浮於氣隙中。傳統軸向磁力軸承結構由上下兩組電磁鐵中夾一組轉子碟盤所構成，由於電磁鐵加上電流後只會產生吸力，故必須分別控制兩組線圈電流以維持轉子在中心工作點位置。此磁力軸承因轉子碟盤較大，所以組裝較為困難，當轉子稍微傾斜也較容易撞到定子。本論文提出一種新型磁力軸承設計，定子結構包含定子線圈與永久磁鐵，轉子部分則由軸與導磁碟盤所組成。此磁力軸承只需單組線圈控制，當激磁繞組加入正電流時轉子會往正方向移動，反之加入負電流則往負方向移動。因為轉子碟盤較小，運作時不會與定子相互碰撞，並且體積較傳統軸承小。本論文使用有限元素分析及田口法設計磁力軸承，對外徑及長度在固定的條件下，最佳化設計使軸承在額定電流內產生最小軸向力20N，以及達到最高效率。除了理論分析設計外，建立一套軸向力量測機構以驗證此設計之軸向磁力軸承性能。

關鍵字

田口法 ； 磁懸浮 ； 電磁致動器 ； 混合型電磁鐵

並列摘要

The rotor suspension system generally utilizes radial and axial magnetic force for making rotor to suspend in the air gap. The structure of the conventional axial magnetic force bearing consists of an upper electromagnet, a lower electromagnet, and a rotor disk that clamped between the upper electromagnet and the lower electromagnet. It should control two groups of coil current individually to maintain the rotor in the position of the central working point, because the electromagnets only can generate attraction. The rotor disk of the magnetic force bearing is so lager that fabrication of the magnetic force bearing is more difficult. In addition, while the rotor slopes slightly, the rotor hits the stator easily.
A novel magnetic bearing design proposed in the paper, wherein the structure of the stator includes stator coil and permanent magnet, and the rotor consists of a shaft and a permeability disk. The magnetic bearing is only controlled by single group of coil. When adding the positive current in the stator coil, the rotor moves in positive direction. On the other hand, when adding the negative current in the stator coil, the rotor moves in negative direction. Since the rotor disk is smaller, the rotor disk can not hit the stator in operating, and the volume of the magnetic bearing in the paper is smaller than the volume of conventional magnetic bearing.
The Finite Element Analysis and Taugchi Method utilized to design magnetic bearing in the paper, under the condition that the out diameter and the length are both constant, the optimal design makes the bearing to generate the lowest axial force 20 N in the rated current and achieve the best efficiency. Besides theory Analysis design, it established an axial measure mechanical for verifying the performance of the axial magnetic bearing performance of this design.

並列關鍵字

Taguchi method ； Magnetic suspension ； Electromagnetic Actuator ； Hybrid Electromagnetic

參考文獻

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