質子交換膜燃料電池系統之設計與控制

Abstract

近幾十年來，由於石油存量耗竭及能源問題日益嚴重，使得燃料電池系統之研究發展備受關注，利用氫氣當作燃料供給燃料電池產生電力之系統主要涵蓋三個議題: 產氫、儲氫與發電；因此，此研究目的在建立一套完整燃料供應設施之質子交換膜燃料電池系統，著重在系統化設計、模式建立與控制方面探討，藉此歸納整理一套系統化之設計流程步驟與合適之控制架構。於模式建立階段，藉由回歸實驗數據獲得模式參數與靈敏度分析方式找出影響製程之重要設計變數，此有助於確定最適化之操作條件與製程改良，最後，設計不同之控制架構評估其可行性與韌性。於製程階段，針對硼氫化鈉水解反應之化學儲氫系統進行動力式、穩態模式建立與最適化設計，使其有效提高儲氫效能，在控制方面為達到穩定產氫速率進而設計兩種可行之控制架構。接著，探討質子交換膜燃料電池系統以實驗數據為輔建立模式，利用穩態分析系統操作變數，設計一有效操作方式以達到電池最高效能。建構一解析之成本模式描述燃料電池系統之經濟權衡關係，以年總成本為考量分析投資成本(質子交換膜)與操作成本(氫氣燃料)進而找出最適化之設計。

The depletion of fossil fuel has lead to renewed interest in fuel cell systems. The last decade has seen significant progress in power generation using fuel cell systems. It is well known that power generation using hydrogen as fuel involves three important issues: Hydrogen generation, Hydrogen storage, and Power generation. The objective of this work is to emphasize systematic approaches to the modeling, design, and control of fuel cell systems. At the modeling stage, a first principles model of a fuel cell is constructed and model parameters are identified via regression from the experimental data (provided by ITRI). Next, sensitivity of dominant process variables to design and operating efficiency is examined. This facilitates locating the optimal operating condition as well as improved design. Finally, a control system is designed to ensure operating flexibility as well as good disturbance rejection. The model of an experimental proton exchange membrane fuel cell for power generation is developed for process design and optimization. An analytical cost model is constructed to describe such an economic tradeoff between capital cost (membrane electrode assembly area) and operating cost (hydrogen fuel) in a proton exchange membrane fuel cell system. At the process level, the kinetics development, modeling and control of a hydrogen storage process (using sodium borohydride) is investigated.