電動車動力系統振動分析與優化設計之研究

Abstract

本研究以華創/華擎車電開發之電動車為研究對象，進行電動車動力系統的振動分析和減振的優化設計。一開始根據文獻回顧，蒐集並歸納電動車動力系統（馬達、減速齒輪箱）模組化結構之振動原因，接著使用有限元素軟體Abaqus建立動力系統模型，並透過模態敲擊試驗驗證模型的準確性。本研究所建立之模型由實體元素和薄殼元素組成，且網格經適當分割，不僅品質較佳的網格可確保分析維持準確性，同時因大幅減少網格的數量，尚能節省大量軟體模擬運算時間。在振動分析中，分別就兩個主要影響振動的因素：馬達轉子動平衡，以及齒輪嚙合進行模擬，並探討個別因素對動力系統振動的影響程度。最後，透過改善振動源和增加結構剛性的方式，產出的優化設計可降低19.9%振動位移。

This thesis studies the vibration influences on the whole drive system of vehicle for HAITEC/CECTEC’s EV car and proposes an optimal design which can reduce vibration. From literature review, this study summarizes the sources of vibration. Then this thesis uses finite element software: Abaqus to create whole model of the electric vehicle drive system. The accuracy of the finite element model is confirmed by the experiment of modal testing. The model is created by both solid and shell elements which is well meshed, so it has better quality and lower quantity of mesh elements, which can not only keep the precision of analysis but also decrease software simulation time. This thesis investigates and simulates two main sources of vibrations: rotor’s unbalance rotating mass and gear meshing during vibration analysis, then explores the importance between each reason and vibration of the whole drive system. At last, this thesis proposes a new optimal design which can lower 19.9% of vibration displacement by improving vibration sources and enhancing the stiffness of structure.