Development Of Distribution Pump Electronic Control System And Its Application On Diesel Engine For Vehicle

Diesel engines have been widely applied in the world because of their efficiency, economy and reliability. However, the traditional diesel engines can not be made progress in the condition of more and more stringent emission regulation. After the Euro-â…¢emission law, none of the VNT turbocharger, fuel injection timing and EGR could be actualized without the engine electronic control. And its typical application is the fuel injection control of the engines. The conception of the fuel injection control system has been changed from a simple control system to an engine management system which includes information technology,fault diagnosis technology,computer application technology,control technology and other new technology. The connotation is extending to a high and wide level. Affirmatively, the electronic control technology of diesel engines is in a new development phase. Combined the trend of the diesel engine electronic control in the world and based on the diesel electronic control fuel injection system, many researches were made on the hardware, software, calibration system, CAN-BUS technology, fault diagnosis technology and matching methods for the electronic control system. The main tasks in this paper include following aspects: 1. Research and development of distribution pump electronic control system With the design of the sensor input circuit, actuator output circuit, ECU and control software, distribution pump electronic control system was established based on CAN bus. The system can achieve not only the closed-loop control of fuel quantity, but also the injection timing control by the needle lift sensor. Both of them are bases of applying, expanding, and developing the electronic control system. During the designing process, the anti-jamming, double ECU, CAN-BUS communication, exterior expand and other technique are used to improve the dependability, stability and real time-performance. 2. Research of electronic control system development environment A new exploitation environment of the electronic control system has been built based on CAN-BUS. It has broken through the limit of the slow communication speed and poor reliability of the traditional communication of the RS232/RS485 between controllers and founded a fast and expedite field bus information channels between ECU and PC. It is also the base of more complicated control and analyzing with PC. In the process of the exploitation environment design, the vision programmer method has been used. This environment could realize the monitoring, collection and on-board calibration of electronic control system parameters and engine performance parameters. And this is also a convenience and comfortable environment for operators to use. 3. Calibration studies on electronic control management system of diesel engine Specified calibration targets and methods were put forward for different operating conditions of the diesel engine. Through measurement of every cylinder speed, the effects of fuel quantity, static fuel delivery advanced angle and other parameters were analyzed and optimized on starting condition. Target idle speed and injection timing should be defined on the basis of stability, low fuel consumption and low emissions. The fuel delivery MAP and injection MAP were defined according to the performance of fuel consumption and smoke. The diesel engine could work normally after the calibration, and the performances of starting and idling were improved.4. Studies of idle speed control methods for diesel engine Because the classical PID is difficult to adjust the control parameters online, it has problems in the diesel engine idle control. For example, it can not satisfy both idle stability and transition requirement. In this paper, fuzzy PID controller has been designed to adjust PID control parameters online, and it has realized better idle stability running and good transition performance . For the variation of different cylinders, the idle balanced control can improve the idle stability further. 5. Development of the integrated on-board fault diagnosis system of the electronic control system Using the large data communications between calibration system and ECU, the integrated on-board fault diagnosis system combined nerve network and logic consequence was implanted in the PC calculation system. Through the comparison of the training error of different training function and different network construction, the nerve network construction and training function were defined. The network after studied had a certain extent popularly using ability, cooperating the logic consequence, could exactly carry out the fault diagnosis under all kinds of the conditions of the electronic control system. The main inventive tasks include following aspects: 1. The design of electronic control system and new calibration system based on CAN-BUS. As a bridge between the double ECU and calibration system, CAN-BUS made data transmission of the whole electronic control system run quickly and reliably. This bridge made the realization of complex control arithmetic and large data real time collection possible. At the same time, the opening construction characteristic of CAN provides the system an infinite spread channel. With the efficient extend of FLASH and RAM, the new manner of the data work and calibration in the system made control system and calibration system be joined closely, as well as independent. 2. Realization of fuzzy PID balanced control on positional electronic control distribution pump.