本文探討之發電裝置為固態氧化物燃料電池(Solid Oxide Fuel Cell, SOFC)，結合史特林引擎以及其他子系統，設計不同系統介面，評估改善並尋找較佳效能之系統，並且藉由有限時間熱傳分析史特林引擎並考量多項 SOFC 輸出電壓之不可逆因子，使得計算之效率可以更加準確。
研究指出系統過往學者以有限時間熱傳考量下分析之系統在燃料加熱過程考量不完善，如本研究之 SOFC 史特林引擎結合回熱器之混合動力系統，即便其擁有最高之效率，卻沒有太大之實用參考價值。在改良燃料加熱介面後之加入加熱器、燃燒室以及兩個熱交換器之SOFC史特林混合動力系統擁有較其他系統較佳之輸出效率，因此是本文探討之主要研究對象。從數值模擬結果得知在溫度較低的 SOFC 工作環境下整體擁有較佳之系統效能，係由於燃料加熱過程在高溫環境需要消耗更多熱能，此外，在固定其他參數下得到燃料利用率越高之情況下，系統握有較優之整體輸出效率。
本研究以考慮 SOFC 之不可逆因子計算其輸出功率，並以有限時間熱傳分析史特林引擎使分析結果更接近實際，此外，在以往考量有限時間熱傳分析之系統的架設上，本文針對燃料加熱系統進行介面設計，使得 SOFC 結合其他系統之效率可以得到提升，最後得到SOFC 混合動力系統之設計以中溫工作範疇(873K)具有較高效率之優勢，其效率在較佳之系統中約高出16.37%。

A cogeneration system based on a Solid Oxide Fuel Cell (SOFC) integrated with a Stirling Engine(SE) and other thermal subsystems. The effects on the system performance are investigated of designing different system interfaces. By analyzing the Stirling engine with finite time heat transfer law and considering multiple irreversible factors of SOFC output voltages, the efficiency of the calculation can be more accurate.
Those systems which took finite time heat transfer analysis into account were not perfectly considered by former scholars in the fuel heating process. For example, the SOFC-SE hybrid system which combined with a regenerator in this study does not have much practical value even if it has the highest efficiency. The system SOFC-SE hybrid system which combined with a burner, a heater, and two heat exchangers which improves the fuel heating interface has better efficiency than other systems, so it is the main research object of this paper. From the numerical simulation results, it is found that the overall system performance is better when the SOFC works at lower temperatures. It is because that the fuel heating process consumes more heat at higher SOFC working temperature. In addition, the system has a better overall efficiency when the fuel utilization rate is higher.
In this study, the output power is calculated by considering the irreversible factor of SOFC, and the Stirling engine is analyzed by finite time heat transfer law to make the analysis result closer to reality. In addition, based on previous systems using finite time heat transfer analysis, we designed the interface for the fuel heating system in this paper, so that the efficiency of SOFC hybrid systems can be improved.

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