دانلود ترجمه مقاله کنترل مبتنی بر مدل چند هدفه برای یک کاتالیزور خودرو – مجله الزویر

• فهرست مطالب:

 چکیده
۱ مقدمه
۲ عملیات کاتالیست
۳ مدل سیستم کاتالیست
۳ ۱ مدل ذخیره سازی اکسیژن در کاتالبست
۳ ۲ اعوجاج سنسور UEGO پس از کاتالیست
۳ ۳ نسبت هوا به سوخت قبل از کاتالیزور و مدل سیستم سوخت
۴ تخمین حالت ذخیره سازی اکسیژن
۵ استراتژی کنترل کاتالیست بر اساس مدل پایه
۵ ۱ الگوریتم کنترل بر اساس مدل
۵ ۲ سوخت و هوا در اگزوز
۶ مثال
۷ نتیجه گیری

• بخشی از ترجمه:

کنترل مبتنی بر مدل غیر خطی ارائه شده در این کار منجر به حداقل رسیدن تولید گازهای گلخانه ای در خودرو شده است. در حالیکه بهینه سازی عملکرد موتور و مصرف سوخت به وجود آمده است. عملکرد موتور و مصرف سوخت در طول عملکرد گذرا با در نظر گرفتن بهینه سازی استفاده از قابلیت ذخیره اکسیژن از كاتاليزور اجازه می دهد تا انحراف از محاسبه میزان عناصر برای مدت کوتاهی از زمان بوده و بدون تولید گازهای گلخانه ای پس از كاتاليزور است. این بازخورد پس از یک برآورد بوده که در حال حرکت در یک مسیر افقی به دست آمده است که برای به حداقل رساندن دخیره سازی اکسیژن و نسبت هوا به سوخت پس از كاتاليزور می باشد. این کار شامل مدل سازگاری برای وابستگی دمای کاتالیزور و نیازهای محاسباتی است که به الگوریتم اجازه می دهد تا در زمان واقعی اجرا شود.

• بخشی از مقاله انگلیسی:

. Introduction The use of three-way catalysts in exhaust after-treatment systems is essential in reducing tail-pipe emissions to the levels demanded by environmental legislation. Although improvements in catalyst formulation and substrate design to reduce automotive emissions are on-going, there is considerable potential for reduction from advanced control of the catalyst operation [1]. As environmental legislation continues to impose increasingly stringent tail-pipe emission regulations, realizing the potential of advanced catalyst control will become more important for regulatory compliance. Model-based techniques offer an attractive advanced control methodology for automotive catalyst systems. A critical aspect of any model-based approach, however, is the ability of the model to predict the dynamic behavior of the catalyst system and the ability to estimate the current state of the system model from available measurements. This work incorporates a simplified dynamic catalyst model that closely captures the dynamic behavior of oxygen chemisorption and reversible deactivation. A moving horizon estimation strategy for the catalyst oxygen storage level based on pre- and post-catalyst wide range or universal exhaust gas oxygen (UEGO) sensor measurements is proposed in this work. This estimator provides accurate dynamic estimates while the state is unobservable and reliable model updates when the state becomes observable. 2. Catalyst operation Key to the operation of three-way catalyst systems is the ability to store and release oxygen resulting from chemisorption/desorption with the cerium oxides contained in the catalyst. Under rich (excess fuel) engine operation, the catalyst oxidizes the hydrocarbons and carbon monoxide present in the incoming exhaust gas by releasing previously stored oxygen. This oxygen release maintains stoichiometric combustion with commensurately low levels of hydrocarbon and carbon monoxide emissions. Because of the finite storage capacity of the catalyst, however, this process cannot continue indefinitely. When the oxygen release rate of the depleted catalyst can no longer satisfy the demand, the post-catalyst air fuel ratio will decrease below stoichiometric and hydrocarbon breakthrough will eventually occur. A typical catalyst control system will therefore attempt to switch to lean (excess air) engine operation before this breakthrough condition is encountered. Under lean engine operation, the excess oxygen in the exhaust gas is now adsorbed onto the catalyst resulting in near-stoichiometric post-catalyst conditions and low tail-pipe emissions. As the oxygen storage capacity of the catalyst approaches its saturation condition, however, the post-catalyst oxygen concentration increases above stoichiometric and breakthrough of nitrogen oxides will eventually occur. A typical catalyst control system will then attempt to switch back to rich engine operation before lean breakthrough. By cycling the engine operation in this way, the oxygen storage capacity of the catalyst can be used as a buffer against breakthrough by compensating for transient oxygen excess or deficiency. This dynamic behavior is clearly shown in Fig. 1 where the post-catalyst air fuel ratio remains essentially at stoichiometric (
۱۴٫۵) for several seconds after the pre-catalyst air fuel ratio makes a lean to rich step transition. Air fuel ratio is defined as the ratio of the air mass flow rate to the fuel mass flow rate. When the oxygen release rate of the catalyst can no longer satisfy the exhaust gas demand, the post-catalyst air fuel ratio begins to become rich until it eventually matches the pre-catalyst air fuel ratio. The separation between the pre- and post-catalyst sensor measurements present between 20 and 70 s is due to sensor distortion in the post-catalyst air fuel ratio sensor as discussed in the sequel. Oxygen storage on the catalyst is clearly shown after the pre-catalyst air fuel ratio rich-to-lean step change made at approximately 70 s.