本研究針對可應用於自由活塞式史特靈引擎之管狀型槽隙式永磁線性發電機進行設計改良與實驗驗證，以降低頓動力並提升發電性能。分別針對動子磁路與定子齒端結構進行改良，透過矽鋼片磁通導引結構改善磁通路徑，並於定子齒端導入靴部以降低槽口所造成之磁阻變化。其後建立三維有限元素模型，並結合多目標基因演算法進行幾何尺寸最佳化，以無載感應電壓與頓動力作為設計目標，選取兼顧輸出性能與頓動力抑制之折衷設計。
依據最佳化結果完成原型機與實驗平台製作，並於不同操作頻率及負載條件下進行性能測試。實驗結果顯示，改良後原型機之低頻驅動扭矩波動較先前設計降低，顯示所提出之結構具有抑制齒槽效應之效果。在固定15 mm衝程下，當操作頻率由5 Hz提高至30 Hz時，無載感應電壓由23.2 V增加至144.3 V；在120 Ω負載下，輸出功率則由2.4 W增加至62.9 W。整體結果顯示，本研究所提出之結構改良與多目標最佳化方法可改善槽隙式永磁線性發電機之電磁性能，並透過原型機實驗驗證其設計與實際發電之可行性。

This study presents the design improvement and experimental validation of a tubular slot-spaced permanent-magnet linear alternator for free-piston Stirling engine applications. The translator magnetic circuit and stator tooth structure were modified using a silicon-steel flux-guiding structure and stator shoes to reduce cogging force while maintaining power generation performance. A three-dimensional finite element model combined with a multi-objective genetic algorithm was used to optimize the design based on no-load induced voltage and cogging force.
A prototype was fabricated and tested under different operating frequencies and load conditions. At a fixed stroke of 15 mm, the no-load induced voltage increased from 23.2 V at 5 Hz to 144.3 V at 30 Hz. With a 120 Ω load, the output power increased from 2.4 W to 62.9 W over the same frequency range. The experimental results demonstrate the feasibility of the proposed design and its practical power-generation capability.

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