Research And Development Of ECU Based On TC1728 High Pressure Common Rail Diesel Engine

With the development of the society, the oil resource is less and less, the pollution of the environment is more and more serious, and the emission regulations are becoming more and more strict. High pressure common rail system is the most advanced and potential electronic control technology of diesel engine, and flexible control of injection can improve power performance and fuel economy of diesel engine with reducing emissions of pollutants. ECU (Electronic Control Unit) is the ’brain’of electronic control high pressure common rail system, and is also the core technology of the development of high pressure common rail system. ECU includes hardware part and software part. Software part includes the strategy and the underlying program. The paper is based on infineon TC728micro controller and focuses on the design of the underlying program of ECU.The YNC30CR diesel engine of electronic control high pressure common rail is selected as the controlled object of the ECU that will be designed. Under the analysis of the ECU function demands, it is clear that there are three parts:the inputs of the engine sensors, ECU, and actuators. The underlying program includes modular partitions:the current Peak-Hold control system of injection driver, engine position management strategy (normal mode, limp modes1,2),the signal acquisitions of engine,the driver of oil metering unit, based on the CCP (CAN Calibration Protocol) the underlying driver of CAN is designed. After analyzing the hardware resources of infineon32-bit microcontrollers TC1728, the underlying driver functions are assigned to different on-chip modules, and the framework of the underlying program is designed.The underlying program is designed based on the idea of modular design, and at the same time debugging is done. Fuel injector driver can drive injector to realize twice injections. The current of fuel injector can rise to18A within100μs when the injection begins. At the end of the injection, the current can fall from12A to0A within30μs. The engine position management system composed by normal mode, limp mode1(only crankshaft signal),Jimp mode2(only camshaft signal), can automatically switch, according to the access of the crankshaft and camshaft signals and realize accurate and rapid determination of the TDC(Top Dead Center) for each cylinder. After realizing the integration of the injection driver and the strategy of engine position management, injections can be controlled by and injection pulse width and the injection advance angle. The configuration and design of the signal acquisition module of the engine is based on the ADC. The program of the fuel metering unit is designed. The he fuel metering unit can be controlled by duty ratio and frequency. Under the research on the TC1728CAN module and the CCP protocol, the CAN the underlying driver and interface program are designed, and the command mode and data acquisition mode of CCP are realized.Based on TC1782the adjustable speed signal is designed to simulate the engine under different working conditions with the signal outputs of the crankshaft and camshaft. The system of underlying software system and the independent development of ECU hardware system is used for simulation test, regarding the simulation of the crankshaft and camshaft signals as the inputs of the system and four fuel injectors as controlled objects. The system under different speeds can rapidly response, determine the injection time and realize pre injection and main injections. Finally the bench test of engine is carried out, the starter motor rotate the engine from0to100rpm, the signals of crankshaft and camshaft are detected by the system and the engine begins to organize injections. The experiment is carried out many times, and the engine can be up and running smoothly.