分析於負載變化下對PEMFC為自主式水下載具電力源的影響

Analysis of the Effect of a Load Change on Proton Exchange Membrane Fuel Cells Used as a Power Source for Autonomous Underwater Vehicles

本文利用Matlab/Simulink軟體進行自主式水下載具於負載切換時對以質子交換模燃料電池作為其電力源的模擬探討，然因燃料電池之輸出電壓易受負載變動及極化損失所影響，故於其輸出端串接電壓模式控制之直流／直流電源轉換器，用以穩定輸出電壓及自動調節自主式水下載具所需之直流5V、12V，24V與48V電壓等級，進而分析自主式水下載具在輕載與滿載間變動對燃料電池端與負載端之電壓與電流的影響。除此之外，本文將非穩態質量與能量原理中控制體積的概念引進燃料電池堆，以獲得實驗量測時難以得到的陽極與陰極流道內之數據訊息和工作機理，並以了解其質量流率、壓力、溫度的暫態與穩態特性。 This paper simulates the electrical transient behavior of proton exchange membrane fuel cell (PEMFC) during a load change using Matlab/Simulink Since the PEMFC output voltage is easily affected by a load change and polarization losses, dc-dc converters are connected to the output of the studied PEMFC for converting the unregulated output voltage to 5-, 12-, 24- and 48-V(subscript dc) for possible applications in autonomous underwater vehicles (AUVs). Moreover, the effect of light- and heavy-toad change on the voltage and current at the PEMFC and load terminals is analyzed in this paper. In addition, the effect of a load change between light- and full-load on the voltages and currents at the PEMFC and load terminals is analyzed in this study. In addition, the concept of control volume in the unsteady state mass and energy theory is applied to the fuel cell stack in order to understand the phenomenon in the cathode and anode channels that are difficult to obtain from measurements. The phenomenon includes the transient and steady state characteristics of the mass flow, pressure, temperature occurred in a PEMFC.