定置型燃料電池混合電力系統之控制及能量管理

Abstract

本論文針對一組6kW定置型燃料電池混合電力系統進行強韌控制及能量管理，使系統電力輸出穩定、並提升系統效率、降低燃料消耗及能量損耗。 此6kW定置型燃料電池混合電力系統係由燃料電池模組、二次電池組及電力元件所組成，為一個交流電輸入直流電輸出之不斷電系統。當市電中斷前，電力元件將市電轉換為直流電輸出於負載，充電器經由市電啟動對二次電池組充電。當市電中斷後，燃料電池模組與鉛酸電池組以並聯式混合電力鏈進行供電；在低負載時，由燃料電池模組獨立供電；在高負載下，燃料電池模組與鉛酸電池組同時供電，故吾人將針對市電中斷後之供電情形進行強韌控制與能量分析。論文工作分為以下四步驟：首先，我們將針對燃料電池模組設計及安裝強韌控制器，以提昇性能；其次，我們替換原鉛酸電池組為具高放電能力的磷酸鋰鐵電池組，進行性能及效率的比較分析；接著，針對系統電力元件如：轉換器、電力開關等元件進行效率分析，了解各元件能量損耗。最後，我們將混合電力系統整合並進行實驗驗證及效能分析。結果顯示系統效率可由58%~79%提升至65%~84%。

This thesis proposes robust control and power management strategy for a 6kW stationary fuel cell hybrid power system to improve system stability and efficiency and to reduce fuel consumptions. The thesis deals with a 6kW stationary hybrid fuel cell system that was developed by a Taiwanese company M-Field. The 6kW system consist of two PEMFC modules, batteries and electrical components to form a parallel hybrid power system. The system was designed for telecom base stations to provide uninterruptible power during emergency power failures. First, the batteries were charged before the main power was shut down. In case of grid power failures, the batteries will start-up the balance-of-plant (BOP) of the PEMFC modules. Then power is continuously provided by the parallel hybrid power system. At low current load, the PEMFC modules provide steady power for the base station. At high current load, both the PEMFC modules and batteries provide electricity to the base station. we apply robust control and power management techniques to improve the stability and efficinency of the stationary system. The study was carried out by four steps: First, we apply robust control to the PEMFC modules to improve the system’s performance. Second, we replace the original lead-acid batteries with lithium-iron batteries, and compare their performance and efficiency. Third, we analyse the efficiency of the electrical components to estimate total energy loss. Lastly, we integrate the stationary fuel cell hybrid power system and verify system performance by experiments. Based on the results, the proposed robust control and power management are deemed effective in improving system stability and performance.