Study And Anlysis For Electronic Controlled System Of High Pressure Common Rail Diesel

As general energy crisis become more and more serious and increasingly rigorous emission legislation, it is necessary for diesel to be developed with lower pollution, lower fuel consumption and high power per weigh. Furthermore, with the development of microcontroller and electronic controlled technology, the diesel using ECU can detect its working parameters at any moment and provides optimal injection timings, fuel injection quantity and injection pressure through calculation of running program. Thus, it improves fuel combustion in diesel cylinder and keeps the good performance of power, economic and exhaust of diesel. Electronic controlled high pressure common rail is one of the three breakthroughs of internal-combustion engine industry in the end of 21st century. It is able to complete the desired fuel injection rate. It is commonly considered to be one of the most effective and economical measurement to resolve the problems of saving energy and protecting environment. At present, studying ECU has become hotspots in the high-pressure common rail diesel system.The paper deeply analyses and studies the ECD-U2 in the working principle, the construction, the design of hardware, software and the control strategy. Firstly, the peripheral components(sensors and driver devices)of system are introduced. The article also analyses the I/O signal processing circuits, the functional blocks of MPC563 and its application in ECU, and shows the detailed design of CAN-bus communication node. Secondly, based on the powerfully TPU module of MPC563, pilot injection has been realized as well as flexible injection timing and duration. With multi-task mechanism ofμC/OS-II introduced, a more real-time, stable, flexible and open common rail control system is built. The paper deeply analyses and studies task partition, the whole software framework, and briefly introduces the calibration software. Then it also analyses the control theory and control strategy of injection pressure, fuel injection quantity and injection timings combined with control theory and the request of special working conditions, such as starting, idling state. Finally, a test bed is established based on a direct injection diesel engine 6106 equipped with ECD-U2 common rail system. Experiments on test bed finish the MAP calibration primarily with the help of the online calibration software, combustion-analysis software and other date-acquired software. Based on the results, the optimization points under different working conditions were got. Performance experiments suggest that CR injection system has a big potential to decrease the emission and improve the performance at the same time for diesel engines.