- 學位論文
質子交換膜燃料電池之混合電力鏈設計與電動輪椅之系統整合
Power Management and System Integration of an Electrical Wheelchair with a Proton Exchange Membrane Fuel Cell
摘要
本論文之目標在於整合燃料電池系統與電動輪椅系統，以質子交換膜燃料電池搭配二次電池，作為電動輪椅的電力來源。研究分為三部分進行：燃料電池的控制、電力管理系統的設計、輪椅馬達的控制與全車之整合。 首先，在燃料電池控制方面，吾人將其視為一雙輸入單輸出的系統，輸入為氫氣與空氣的流量，輸出為燃料電池的電壓，透過強韌控制器的設計與安裝，以達到穩定輸出電壓的目標，並同時減少了氫氣消耗與能量消耗。 其次，將燃料電池搭配兩組磷酸鋰鐵電池，規劃串聯式混合電力鏈，依據它們的動態特性，制定合適的電力管理策略。首先建立充電與供電迴路，其中一個電池組提供電力給後端負載，另一個電池組作為備用電力。當第一個電池組的電量降至一個選定值時，切斷其供電迴路並控制燃料電池以定電壓對其進行充電，而當其供電迴路被切斷的同時，另一個備用電池的供電迴路會被打開，使後端的電力供應不會間斷。由實驗結果顯示，整個電力轉換和傳輸的過程相當成功。 最後，進行電動輪椅馬達的控制，利用馬達控制卡與二維操縱搖桿，控制雙輪馬達的行進、加速與轉向。並將前面所設計的兩個子系統與電動輪椅進行系統整合，以提供電動輪椅穩定且持續的電力供應。
並列摘要
This thesis proposes control and integration of a fuel-cell powered wheelchair. The study was carried out in three steps: the fuel-cell control, power management, and system integration. First, we apply multivariable robust control strategies to a 500W proton exchange membrane fuel cell (PEMFC) system, which has inputs of air and hydrogen and outputs of stack voltage, to provide steady electrical power. Second, we design a serial power-train for the electric wheelchair. The power system consists of the 500W PEMFC, two 6.9Ah LiFePO4 battery sets, and two 300W electric motors. The motors are directly driven by the battery sets in order to avoid damaging the PEMFC by rapidly varying loads. And the battery sets are charged by the PEMFC when their capacities drop to a certain level. From the experimental results, the power management system is successful in providing uninterrupted electricity to the wheelchair. Lastly, we apply a motor control card and a joystick to regulate the motions of the wheelchair motors. Then we integrate the aforementioned sub-systems and demonstrate the effectiveness of the system by experiments.