The Hardware Design And Implementation Of Dual-fuel Engine ECU

Recently, the air pollution is increasingly serious, of which the main source is automobile exhaust. So the emission standard is more and more strict. In addition, excessive exploitation of petroleum leads to the increasingly scarcity of petroleum reserve. Under the pressure of environmental protection and energy reserve, the research of alternative fuel is urgent. Natural gas has become the most practical alternative fuel because of excellent characteristics. According to the current situation of the development of China’s automobile, it is hope that the natural gas can be used in diesel engine by the mode of blending, without changing the internal structure of the diesel engine. Therefore it has great strategic significance and practical value to develop a universal electronic control unit(ECU) to blending engine.The electronic control system of blending engine was based on the mainstream high pressure common rail diesel engine. It was developed by increasing a set of parallel blending ECU and necessary sensor device on the basis of the diesel engine electronic control system. By improving the method of control to optimize the process of blending combustion, low emission targets can be achieved in the case of using oxidized catalytic converter. The relationship of the blending ECU developed and the diesel engine ECU is parallel: in the mode of pure diesel, the control of diesel nozzle belongs to the diesel ECU; in the blending mode, the control of diesel nozzle belongs to blending ECU, and the diesel ECU does not produce false alarms. The blending ECU not only has the function of gas injection, but also can implement active control of diesel injection and the conversion of the combustion mode.According to the design requirements and control idea of blending ECU, the design of hardware circuit of blending ECU has finished, including power circuit, control circuit, signal processing circuit, electronic throttle driving circuit, natural gas and diesel injection circuit and the communication interface circuit. The programming flowchart of diesel injection circuit was given in this paper. Finally, the test results showed that the nature gas driving circuit performed well.