自主式水下載具負載切換對電力源為質子交換膜燃料電池之輸出電壓與輸出電流的影響

Effect on the Output Voltages and Output Currents of Proton Exchange Membrane Fuel Cell Used as Power Sources for Autonomous Underwater Vehicles during Load Change

本文以加拿大Ballard公司所開發SKW質子交換膜燃料電池Mark V作為自主式水下載具電力源，並選擇以純氫及純氧為反應氣體，分析於一般工作溫度範圍與氣體工作壓力對其極化曲線的影響。再則，因燃料電池之輸出電壓易受負載變動及極化損失所影響，其直流輸出電壓會不穩定。本文根據Ballard公司所提供燃料電池輸出電壓之範圍，設計以電壓模式控制之直流／直流電源轉換器來自動調節電壓，以提供自主式水下載具設備為直流電壓5V、12V、24V與48V等負載之所需，並分析負載切換對燃料電池端與負載端輸出電壓與電流的影響。 This paper uses a 5kW Ballard PEMFC (proton exchange membrane fuel cell) Mark V manufactured by Canadian company as power sources for autonomous underwater vehicles. The PEMFC works with pure H2 and O2 as the reactant gases. Moreover, the effect of the operating temperature and operating pressure on the polarization curve of PEMFC is analyzed in this paper. Since the output voltage of PEMFC can be easily affected by load variations and polarization losses, its output voltage is not stable. Thus, a DC/DC power converter with a voltage mode control is designed to automatically regulate the output voltage of PEMFC in this paper. Based on the output voltage of Ballard PEMFC, the output voltages of 5V, 12V, 24V and 48V DC can be obtained to supply for autonomous underwater vehicles. Additionally, the effects of load change on the voltages and currents at the source and load terminals are investigated in this paper.