質子交換膜燃料電池系統的系統層次性能分析

System-Level Performance Analysis of a Proton Exchange Membrane Fuel Cell System

本論文係從系統層次的觀點，運用GCtool 軟體來進行質子交換膜燃料電池系統的生能分析，經由系統化的公式推導，燃料電池多數的操作參數可以由燃料電池方程式及經驗值獲得，其中最重要的參數為燃料電池的工作壓力、溫度和質子交換膜兩面的壓力差。以一個100 kW、轉換效率45%、燃料使用率80% 的質子交換膜燃料電池堆為例，經由系統層次的性能分析，其最佳的操作壓力及電極兩端的壓力差分別為4 大氣壓力和0.1 大氣壓力。質子交換膜燃料系統包含輔助設備的全系統轉換效能可達49%，同時隨著操作溫度的增加，全系統的轉換效率可以再提昇，工作溫度的選擇需考量熱穩定和濕度管理。 This report presents a performance analysis of a proton exchange membrane fuel cell (PEMFC) system, using GCtool software, from a system-level perspective. By systematic formulation, most of the operating parameters are derived through fuel cell equations and from empirical data. The most critical parameters are the working pressure and temperature of the fuel cell as well as the pressure gap across the cell membrane. When given a 100kW PEMFC stack with 45% efficiency and 80% fuel utility, the working pressure and its difference are selected at 4 atm and 0.1 atm via the system-level performance analyses. The selection of the working temperature of the PEMFC should take both thermal stability and humidity management into consideration. A PEMFC system with certain auxiliaries can achieve an estimated efficiency of more than 49%. It was found that the efficiency of the PEMFC system can be promoted with an increase in the working temperature.