Abstract
摘要 本文針對半導體製程設備中的渦輪分子真空幫浦之磁浮軸承系統來進行研究，本系統所使用的軸承系統為被動式的磁浮軸承，首先將使用以有限元素法為理論基礎的商用工程分析軟體(Ansoft Maxwell)作為分析磁斥力的工具，以計算磁環間的磁斥力，同時分析磁場改變對軸承剛性的影響，進而討論軸承剛性改變時對系統整體的性能有何影響，為了與磁斥力的分析結果進行比對，本研究設計了一套磁力量測平台，將磁浮軸承上的磁環實際裝置於量測平台中進行斥力量測，以比對模擬值的正確性與否，並比對模擬值與量測值的誤差。 依據分析軸承剛性的基礎，來討論目前被動式磁浮軸承在實務上所面臨的一些裝配及不穩定的因素，藉此瞭解被動式磁浮軸承的行為特性。最後將藉由參數分析了解磁環的設計參數，如氣隙大小、磁環厚度、高度、間距及層數，找出主要影響磁環性能的主要參數，並利用分析結果來調整磁環的幾何形狀及組成結構，以提升整體磁浮軸承剛性及性能，進而增加系統的穩定性，以提供日後設計被動式磁浮軸承時的設計之依據。 Abstract This research was focused on the passive magnetic bearing system of a turbo molecular pump (TMP) used in semi-conductor manufacturing processes. First, this study will analyze magnetic fields by using the FEM analytical software (Ansoft Maxwell) to understand the magnetic circuit. This study will also analyze the effects on bearing stiffness when the magnetic field is changed, and then discuss the effects on system when the stiffness is changed. To compare the magnetic force test results with the analysis results, this study has designed a magnetic force test platform. By installing the magnetic ring on the test platform, we can test the correctness of the simulation results. According to the bearing stiffness analysis foundation, this study will discuss problems from system assembly and unstable factors to understand the dynamic behavior of the system. In order to improve the magnetic bearing stiffness and performance, this study finds the main parameters which affect the TMP performance. By parametric analysis of the magnetic ring, including gap, depth, height, distance and layer number, we can adjust the geometry and structure of the magnetic ring with these analysis results.