熱配馬達轉子對轉軸動態特性之影響與其有限元素建模之探討

The Effect on the Dynamic Characteristics of a Rotating Shaft by Interference Fitting the Motor Rotor and Its Finite Element Modeling

一般而言，分析一高速主軸的動態特性時，有限元素分析為一相當重要及常用的方法。然而，有限元素法的分析結果常會有所誤差，此誤差乃由於有限元素法所建立的模型與實際系統的差異所致。因此，本文提出以模態測試的結果修正有限元素法所建立的模型，使得有限元素模型能夠更加精準，並且能用其做更進一步的分析。另外，本文以一每分鐘三萬轉的馬達內藏式高頻增速器為研究對象，探討轉軸因轉子干涉配合所造成的動態特性變化，並提出可行的有限元素模型修正方式，由修正結果的比對顯示，此種修正方法具有其實用性。

The finite element method is the major way to analyze the dynamiccharacteristics of a high speed spindle. However, the behavior of a systemobtained by finite element modeling is different from a real system. Theerrors come from the difference between the finite element model and thereal system. Therefore, we propose a modified finite element modelmethod by using modal testing results. The modification can improve theaccuracy of an original finite element model and can be used for furthernumerical analysis. In this paper, a 30,000 rpm speed-booster spindle withbuild-in motor is used as a study case. The interference fitting effect of amotor rotor is discussed. In this case study, we introduce a feasible modificationapproach to improve the finite element model. In comparison withresults obtained by the modified finite element model and experiments, thisimproved method shows its practicability.