Modelling of the Dynamic Processes in an Electronic Diesel Fuel Injection System 920240
The new generation of electronic Diesel fuel injection systems with special solenoid valves presents a complicated mechanical/electrical system. It involves a combination of mechanical motion, hydraulic pressure wave propagation, and the transient magnetic and electrical processes which interact with other. In this paper, the coupled dynamic behavior of the new system is studied based on a research type electronic pump-pipe-injector system developed by authors. A general physical model is established, which includes other structure types such as the electronic unit injector and the electronic distributor pump system.
Traditional mathematical models for conventional mechanical injection system or conventional solenoid valves, alone or simply connected, are not suitable for the new type of injection system. Therefore, a new comprehensive mathematical model is formulated. It incorporates a simplified characteristic line method for determining the hydraulic transients in high pressure fuel lines and a transmission line analogy method for solving magnetic processes in the solenoid. The coupling dynamics of the electro-magnetic and hydro-mechanical processes in the system are represented by ordinary differential equations.
The computer simulation of the system is performed on a personal computer. In order to check and improve the modelling accuracy, a special test stand was developed and dynamic measurements carried out. The verification through comparison with the experimental data shows that the simulation results agree well with experiment results.