二甲醚发动机电控低压燃料喷射系统的设计

针对二甲醚燃料低粘性、高蒸汽压以及容易与空气形成混合气的特性，开发了电控低压燃油喷射系统，进行了系统的总体设计、电子控制单元(ECU)的软硬件开发和在油泵台架上的试验。电控系统软件采用实时模块化编程，具有编程灵活，移植性和扩展性好的特点。试验结果表明，在新开发系统的驱动下，喷油器启合及时，喷射有力，雾化效果好；所开发的软件能实现信号采集、发动机各丁况控制，满足了发动机正常运行、反馈控制及信号采集的实时性要求。

Development of the Low - pressure Common Rail Fuel System for a Dimethyl Ether Engine

The low-pressure common rail fuel system was developed according to the properties of dimethyl ether(DME),such as high saturate vapor pressure and low viscosity and easy formation of mixture with air.The electronic control unit(ECU)for the system consists of hardware and software.The hardware includes following major components:sensors,input circuits,electronic control unit,output circuits,and actuators.The software was designed on the basis of real-time and modular principle characterizing good flexibility,transplant convenience and extending possibility.The developed software performs input signal sample,engine operation conditions control and output control.The software should meet the real-time control requirement of engine operation,feedback control and analogue signal sample.The microprocessor interruption system is used for duty dispatch.Fundamental experiments were conducted on pump test bench to get the fuel injection quantity map and the fuel injection timing map.Test result shows the feasibility and good comprehensive performance of low-pressure common rail electronic system for DME fuel.