黃光裕臺灣大學:機械工程學研究所周尚德Prajna, BudiBudiPrajna2007-11-282018-06-282007-11-282018-06-282005http://ntur.lib.ntu.edu.tw//handle/246246/61256當一導電體受到一時變磁通量時,在導電體中即會產生渦電流,渦電流會產生與時變磁場磁極方向相反的磁場(二次磁場),磁場的相互作用即產生抵抗磁場變化的力量。藉由導電體的電阻,會將渦電流以熱損耗方式釋出,如此則可以消耗掉意圖改變磁場之振動動能,而達到減振的效果。本論文的研究目的在於設計製作可靠且高性能的轉軸渦電流減振系統,使其能滿足小型轉軸在偏擺時所需要的減振功能。首先彙整參考文獻及探討轉軸渦電流減振的作用原理,並在評估許多設計參數與變異性之後,從而進行轉軸渦電流減振系統的實體設計以及組裝。本論文同時從理論模型以及有限元素模型的分析,了解各個設計參數對於渦電流減振作用的影響。接著對所完成的轉軸渦電流減振系統進行動態特性的測試,以減振力、阻泥比和減振時間常數來評比減振系統之性能表現。在提升減振系統的性能上,提出了雙環形磁石排列方式以及環形Hallbach磁石排列方式,可以提升減振效能使阻尼比2~4倍,另外對也提出渦電流限轉磁石配置方式,可以改善高轉速不穩定現象。When a conductive material is subjected to a time-varying magnetic flux, eddy-currents are generated in the conductor. These eddy-currents circulate inside the conductor generating a magnetic field of opposite polarity as the applied magnetic field. The interaction of the two magnetic fields causes a force that resists the change in magnetic flux. Due to the internal resistance of the conductive material, the eddy-currents will be dissipated into heat, consuming the kinetic energy of the vibrating element, the conductor or the magnet, which causes the time-varying magnetic flux, and thus producing a damping effect. The aim of this thesis is to develop a reliable and high performance of rotor eddy-current damping system which satisfies the damping capability needed to absorb the lateral vibration of small rotating machinery. This thesis will first investigate and analyze numerous literature surveys on working principle of rotor eddy-current damping. The thesis then advances to estimation of numerous design factors and variations of fabrication process. Theory model analysis as well as finite element analysis are being used to understand the influence of different design variables on the damping system. Dynamic characteristic testing is applied to evaluate the damping system performance by comparing damping force, damping ratio and damping time constant on various designs. Finally, this thesis proposed a novel double ring magnet arrangement and a novel Hallbach ring magnet arrangement, which improve the damping system performance by increasing the damping ratio by 2~4 times. Eddy-current rotation restriction magnet arrangement is also being introduced which has been proven to greatly improve the instability problems during the high speed operations.誌謝 I 中文摘要 II 英文摘要 III 目錄 IV 表目錄 VII 圖目錄 VIII 符號表 XII 第一章 緒論 1.1 研究背景與動機 1 1.2 文獻回顧 3 1.3 內容簡介 11 第二章 小型轉軸渦電流減振系統之工作原理與理論 2.1 渦電流介紹 12 2.2 渦電流的應用 18 2.2.1 渦電流用於能量或力量的產生與轉換 18 2.2.2 渦電流量測原理之運用 21 2.3 渦電流減振之工作原理 22 第三章 小型轉軸渦電流減振系統之設計開發 3.1 概念設計 27 3.2 實體設計 35 第四章 理論模型建構與模擬分析 4.1 理論模型建構 43 4.2 有限元素模擬分析 51 4.3 系統運動方程式 55 第五章 小型轉軸渦電流減振系統之測試與特性分析 5.1 實驗架構 59 5.2 系統測試 68 5.3 影響參數探討 76 5.3.1 導電圓盤材料的影響 76 5.3.2 導電圓盤厚度的影響 77 5.3.3 導電圓盤直徑的影響 79 5.3.4 空氣間隙的影響 81 5.3.5 相對移動速度的影響 81 5.3.6 磁石排列型式的影響 82 5.3.7 導電圓盤形狀的影響 85 5.3.8 導電圓盤旋轉速度的影響 87 第六章 結論與未來展望 93 參考文獻 95 附錄A 伺服馬達規格與特性 98 附錄B 編碼器規格與特性 99 附錄C 伺服馬達控制器規格與特性 100 附錄D 雷射位移量測器規格與特性 101 附錄E 測力規規格與特性 102 附錄F 資料擷取卡規格與特性 103 附錄G 電磁鐵規格與特性 105 附錄H Matlab程式:實驗運動曲線與指數衰減 106 附錄I Matlab程式:理論運動曲線 108 附錄J 渦電流減振系統架構設計圖 11210242460 bytesapplication/pdfen-US渦電流減振小型轉軸多樣化設計效能評比實驗與分析eddy-current dampingsmall rotorvariety designsperformance evaluationexperiment and analysis小型轉軸渦電流減振系統之開發與特性探討Development and Characteristic Study of a Small Rotor Eddy Current Damping Systemthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/61256/1/ntu-94-R92522617-1.pdf