The Study Of Control Strategy For High Pressure Common Rail Diesel Engine-Analysis On Strategy Of Engine Position Timing

With the energy sources and environment problem becomes increasingly prominent, the realization of energy saving and exhaust reducing has important significance. The using of high pressure common rail injection system becomes more and more applicable for it has the extrude advantage in the field of economy, power performance and reducing noise of diesel engine. The main characteristics of high pressure common rail injection system are list as follows:the injection pressure is flexible adjustable, injection timing can be controlled autocephaly agility, injection amount of oil can be adjustable freely and the injection rate figure can be controlled flexible. Based on these advantages, the high pressure common rail injection system was considering being the most efficiency and economic means to resolve the environment protection and energy saving double pressure. The research of electronic control system of diesel engine has important significance in improving of technology progress and independent study ability of our country.This thesis based on the scientific research "development of energy saving and high efficient gas engine for new type saloon car". After widely consult of home and abroad correlation literature, the control soft and strategy of high pressure common rail injection system were researched. The layered modularized method was adopted to design the control soft. Static structure of soft contains application layer, equipment layer and core layer. Dynamic process of soft adopts front ground and back ground structure, including main program and interrupt service program. The main programs complete the system initialization at first, then it carry through the collectivity prepare process and it was belong to the back ground of the soft. The interrupt service program deal with asynchronism affairs and it carry out the main test, monitor and timing synchronization and other tests. By analyzing the system structure and control theory of high pressure common rail injection system and carrying out the research of control strategy, the control strategy of camshaft sensor and crankshaft sensor were designed based on oil injection timing for signals from this sensors were important for the running of ECU. The engine bench test result shows that the control program of ECU can realize the start of engine smoothly; in the idling condition, the rotate speed of engine fluctuated in the normal field; the injection pulse width and time was match with the set value; the control strategy and soft design has a good real application effect.