电控柴油机电磁阀驱动电路优化设计

Optimization Design of Solenoid Drive Circuit for Electronically Controlled Diesel Engine

电控燃油喷射系统是电控柴油机的重要组成部分,作为喷射系统执行器的电磁阀,其驱动性能研究是一个重要课题。在对现有电控柴油机电磁阀驱动电路进行分析的基础上,设计了一种优化驱动电路。该系统采用120V高压和24V低压双电源系统分时驱动,从硬件上实现了电磁阀喷射电流的自动PWM反馈调制。试验结果表明:该系统显著缩短了电磁阀闭合时间,降低了系统功耗,同时可减少ECU中断响应次数,对ECU资源占用较少。

An electronic fuel injection system is suitable for a diesel engine to meet the emission regulation. How to drive the high-speed solenoid of a fuel injection system was an important issue in the ECU hardware design. Based on the experiment and analysis of a conventional drive circuit, a new optimum schematic was designed. Two driving voltage sources with 120 V and 24 V were adopted in different driving stages, and the solenoid current was controlled by the hardware PWM signal, whose duty was automatically tuned by the current feedback signal. An onboard DC/DC boosted the 24 V battery voltage to 120 V. The experiment results show that the rising up time of the solenoid is shortened while the drive energy consumption of the solenoid is minimized, as well as the software interrupt times related to the injection control process is significant reduced.