- 學位論文
應用線上系統判別油膜動態於V2引擎之空燃比控制
Air Fuel Ratio Control for V2 Engine Using On-line System Identification of Fuel Film Dynamics
摘要
本研究配合國內車輛產業之需求與發展，針對燃油噴射系統於歧管產生之油膜動態、引擎模型進行探討。在引擎模型方面，利用MATLAB/SIMULINK建立一設計導向及控制導向之引擎模型，其模型可應用於各式引擎車輛引擎管理系統之策略發展。研究之目標引擎為1000cc V2雙缸四行程火花式點火引擎。在其引擎模型中可分為五大子系統，分別為：進氣動態、燃燒動態、燃油動態、摩擦動態以及旋轉動態，利用上述各子系統模型計算並經由引擎實驗數據驗證後，即可模擬出實際引擎動態。在油膜動態方面，不同情形下的引擎操作點，將會影響進氣歧管中油膜的特性參數，因此引擎管理系統需計算及預測現實歧管中的油膜動態，進而更加精準地控制空燃比在指定的目標上。此研究目標將建立一控制器，並利用系統判別中遞迴最小平方法(Recursive Least Square, RLS)並在基於事件(Event-Based)的架構下去識別引擎中的油膜動態模型，最後加入燃油控制器於引擎模型中來評估驗證所提出之控制策略。由模擬顯示，油膜之動態參數經由RLS可精準的判別；另外，利用卡爾曼估測器將窄域含氧感知器信號處理成似廣域含氧感知器之信號，其優勢可減少額外增加感知器之成本。最後將線上系統判別、卡爾曼估測器結合於模型預測控制器來進行空燃比閉迴路控制，經由模擬結果可得知在穩態時空燃比的表現可精準地控制在理論空燃比，而在暫態時，亦能快速收斂至理論空燃比。
並列摘要
Due to requirement and development of vehicle industry in Taiwan, this research focuses on fuel film dynamics in the intake manifold of port injection system and V2 engine model. In engine model, it uses MATLAB/SIMULINK to build design oriented and control oriented engine models. These models can help engineers to develop strategy of engine management system. The target engine is a 1000cc, V twins, and four-stroke spark ignition engine. In this engine model, it can be departed five sub-models. These are charging, fueling, combustion, friction and rotational dynamics. By using above five sub-models, the engine model can simulate the actual engine dynamics. In fuel film dynamics, it is one important part of engine dynamics because it affects engine’s fuel consumption and emissions. There are two important parameters of fuel film dynamics, and they are affected by different engine operating points. In order to precisely control air fuel ratio on the actual target, the engine management system has to calculate and predict real fuel film dynamics in the intake manifold. Therefore, recursive least square (RLS) is used to identify fuel film parameters and it is built by event-based structure. The identification parameters are added in the fuel controller, and then it is verified at different situations in the V2 engine model. By the results of simulation and experiment, fuel film identification parameters are good to use in many engine operation points.