汽车发动机的变结构控制和智能控制方法研究

【作者】 葛召炎；

【导师】 彭永进；

【作者基本信息】 湖南大学 ， 控制理论与控制工程， 2003， 博士

【摘要】 在汽车发动机的控制中，转速和燃油控制是二个非常关键的项目，特别是自动化高速公路计划(Automated highway project)提出来以后，寻求一个较好的解决汽车发动机转速(汽车速度)控制方案是现代汽车工业面临的一个新课题。发动机燃油控制的质量直接影响到发动机的工作性能，一直是人们研究的重点。汽车发动机使用环境变化大，使用条件有时非常恶劣，从寒冷的冬天突然启动进入行驶状态，行驶过程中的突然加速，急剧的扭矩变化等等，在这样的条件下，为了使其热效率、输出功率、行驶性、安全性和排气清洁性处于最佳状态，给汽车发动机的控制带来了极大的困难，特别是零排放汽车排放标准的提出，对发动机控制提出了更高的要求。 汽车发动机是一个典型的非线性、时滞、时变系统。而变结构控制适应于线性与非线性、连续与离散、确定与不确定、集中参数与分布参数、同步与时滞系统，具有一定意义下的完全鲁棒性。智能控制能够将人类的智慧应用到控制系统中去，解决非线性、复杂的系统控制问题。本文通过一个具体的汽车发动机模型，采用滑动模态变结构控制(SMC)和智能控制(NC、FSMC)方法，对汽车发动机转速和空气—燃油比(A／F)的协调控制进行了研究。根据汽车发动机控制的特点，提出了新的燃油喷射规律和在特定条件下设计滑模面的方法；引入了转速与A／F控制的二维滑模面，采用发动机的线性与非线性模型，对SMC控制器进行了设计；对发动机转速神经控制的结构和神经网络的形式进行了研究；将模糊控制与变结构控制相结合，很好地解决了发动机转速与燃油变结构控制中出现的转速抖振问题；同时对SMC控制器和智能控制的硬件与软件进行了设计研究。仿真结果表明，变结构控制和智能控制是解决发动机转速与燃油控制问题非常有效的方法。更多还原

【Abstract】 Speed and fuel control are key issues in automotive engine management. A good solution to speed control is very important to automated highway project. Fuel control relating to engine performance is always a research emphasis. Engine operating conditions cold be changed quickly and are very bad sometimes, such as: from suddenly cranking to driving in winter, acceleration to sudden torque demand. In the light of zero emission vehicles, in order to achieve better hot efficiency, maximum power, higher safety and best emission, engine controls become more and more difficult.Automotive engines are typical nonlinear, time-delay, time-varying parameter systems. Variable structure control is suitable for linear and nonlinear, continual and discrete, certain and uncertain, integrated and discrete parameter, synchronous and time-delay systems. Intelligent control can solve many complex system control problems by integrating human knowledge into control systems. In this paper, simultaneous controls of speed and air-fuel ratio (A/F) in an automobile engine mode are studied based on sliding mode control (SMC) and intelligent control (NC, FSMC), a new fuel injection strategy and a sliding surface design method according to engine control are proposed, speed sliding surface and A/F sliding surface have been used, the structures of speed neurocontrol are researched, fuzzy control has been applied to reduce chattering in SMC. Hardware and software designs of SMC controller, neurocontrol and fuzzy-SMC are presented. Simulation results show that SMC and intelligent control are efficient approaches to solve automotive speed and A/F control problems.更多还原