基于模型的高压共轨柴油机轨压控制

Model-based controller framework for a common rail diesel engine

为满足新型低温预混合燃烧柴油机燃烧模式切换时的瞬态轨压控制的要求,在结合传统PID控制算法的基础上,提出了一种基于模型的共轨轨压控制结构。通过建立包括轨道、喷油器、高压泵和ECU(engine control unit)驱动特性的共轨系统的前馈物理模型,配合燃油泄漏补偿模块,并应用控制质量评估和切换策略,使得该方法不仅结合了传统PID算法稳定可靠的优点,还具有响应快、不超调以及标定简单等新特点。实验结果表明:该控制算法明显改善了瞬态过程中的轨压控制精度并能保证控制系统在实际应用中安全稳定的要求。目前该算法已应用于中国新一代低温预混合燃烧柴油机产品样机的开发。

An advanced model based controller was developed to enable fast transient response of the rail pressure to control the combustion with premixed charge compress ignition. The model combines a feedforward model for the rail, injector, and pump and engine control units （ECU） models with a leak compensation module and a control quality signal monitoring module so that the controller has the advantages of a traditional PID controller with fast response, no overshoot and easy calibration. Experiments show that the controller greatly improves control of engine transients and is able to ensure system safely. The controller has been used in the engine management system of a new generation diesel engine.