本論文主要目的是將質子交換膜燃料電池系統視為多輸入多輸出之系統,並利用頻譜分析儀對燃料電池作單輸入單輸出的系統識別,分別為空氣幫浦電壓與比例閥電壓對燃料電池的輸出電壓與電流。 頻譜分析儀所獲得的資料,藉由Levy’s method作為曲線擬合之演算法,可以獲得:(1)分子分母同為2階之轉移函數適合用來描述空氣幫浦電壓對燃料電池輸出電壓或電流、(2)燃料電池系統參數因負載不同而改變,必須透過線上參數估測、(3)氫氣流量對燃料電池輸出電壓或電流影響不明顯,可簡化燃料電池系統。 透過系統識別可以發現燃料電池系統可以簡化為空氣幫浦電壓對燃料電池輸出之關係,控制策略可以使用適應控制穩定燃料電池之輸出電流。而氫氣端影響不明顯,故著重於氫氣使用量之節省。
The purpose of this research regards a PEMFC as a MIMO system, and makes identification for four SISO of a PEMFC with dynamic signal analyzer. The four SISO identifications are air pump voltage and proportional valve voltage to fuel cell voltage and current. The data got from dynamic signal analyzer is fit by Levy’s method. Then, some results can be gained : (1) the transfer function which the numerator and denominator order are second order can be used to describe air pump voltage to fuel cell output voltage or current (2) the parameter of fuel cell system is changed by different load, so it needs to use on-line estimator (3) hydrogen flow rate doesn’t have significant influence on fuel cell output voltage or current, so the fuel cell system model can be simplified. Form system identification, the fuel cell system model can be simplified as air pump voltage to fuel cell output. The air control can use adaptive control to make fuel cell output stable. Then, the hydrogen control can focus on saving hydrogen.