Title: 燃料電池供電系統之雙鋰電池充電效率控制
On Charging Efficiency of Dual Li-Ion Batteries for Fuel-Cell Electricity System
Authors: 葉展嘉
Chan-Chia Yeh
董蘭榮
Lan-Rong Dung
電控工程研究所
Keywords: 直接甲醇燃料電池;鋰電池;直流轉換器;數位控制;濃度控制;混合;DMFC;Li-Ion Battery;DC-DC;digital control;fuel sensor-less control;hybrid
Issue Date: 2008
Abstract: 有別於傳統之串聯式與並聯式架構鋰電池使用壽命過短之議題,本論文提出一新穎的燃料電池與雙鋰電池混合供電系統。本系統之最大特色是採取雙鋰電池交互供電策略,一個鋰電池專司負載放電,另一接受燃料電池電力充電,如此可避免鋰電池在傳統架構上遭受過充與過放使壽命減短之傷害。
本架構並結合燃料電池濃度控制、最大功率點追蹤與高效率動態電流充電成一完整系統。利用最大功率點追蹤電路結合脈衝響應燃料注入法,可將燃料槽之甲醇濃度準確的維持在一定值,並且不受溫度等環境因子影響;高效率動態電流充電則可使鋰電池有較快的充電速度與充電效率。此外,配合燃料電池在不同溫度下最大輸出功率之變化,本系統亦綜合考量燃料電池在不同的電力供應能力下之負載平衡議題,提出合理的演算機制。
本論文另將類比控制器參數全數位化,採用數位控制器達成上述之演算法與電路機制,以求未來實作上將有機會進一步縮小控制器體積。並透過模擬軟體,編輯C語言以實現數位邏輯運算功能,給予電路模型合理的控制命令。最後的模擬結果顯示,在不同溫度下此混合供電系統均可符合演算法預期之運作機制,可證明此燃料電池與雙鋰電池混合供電系統在實作上確實可行。
One of the important issues in traditional parallel and series structure of hybrid fuel cell/Li-Ion battery power supply is the battery life too short to use. In this paper, we propose a novel hybrid system that combines dual Li-Ion batteries with a fuel cell to deal with these issues. The control strategy presented in this paper is able to track the maximum power point of the fuel cell, sustain the fuel concentration in mixing tank and regulate the charginging current of the Li-Ion battery.The controller parameters are designed by discretization of analog controller. It will be easier to implement computational functions and more flexible in modifying the code for other applications. Simulating results present the feasibility and generality of the control strategies.
URI: http://140.113.39.130/cdrfb3/record/nctu/#GT079512521
http://hdl.handle.net/11536/41078
Appears in Collections:Thesis