时间控制式柴油喷射系统初期喷油率控制方法

针对柱塞泵时间控制式柴油喷射系统的特点，提出了一种利用柱塞上设置的泄流槽和电磁旁通控制阀相配合来调节初期喷油速率的新方法，该方法具有结构简单、调节灵活、控制稳定等优点。介绍了该方法的控制原理和系统结构，通过建立电控直列泵－管－阀－嘴柴油喷射系统（ＰＰＶＩ）的计算模型，进行了泄流槽结构参数的选配，试验研究了泄流槽尺寸、转速和喷油定时等对喷油速率特性的影响。研究结果表明，该方法对时间控制式柴油喷射系统的初期喷油速率能够实现有效的控制

Initial injection rate control method in solenoid-controlled Diesel injection systems

A new initial injection rate control method in solenoid controlled Diesel injection system was introduced in this paper. The basic idea of this method was to maintain a small spill passage between plunger chamber and inlet port during initial injection period. The initial injection rate could be trimmed by changing the closing timing of the solenoid controlled spill valve. This method has the advantages of simple construction, feasible adjustment, and stable performance. Computer aided analysis and design based on a simulation program of the system were conducted to compare and select the size of the small spill passage according to their effect on injection characteristics. The experimental research on a special pump test rig was carried out. The results indicate that this method is effective for the control of initial injection rate and pilot injection in time based electronic Diesel injection system.