汽车燃油喷射系统用磁致伸缩驱动构件的建模与特性研究

Study on Model and Characteristics Analysis of the Magnetostrictive Drive Component of Automotive Fuel Injection System

针对传统发动机喷射系统存在的非无级控制及喷射量难于精确最小化的问题,论文提出一种利用磁致伸缩致动器直接驱动喷嘴针控制燃油喷射过程的磁致伸缩喷射系统。通过调整磁致伸缩材料变形量以快速无级控制喷射器开合尺寸及喷射量。以基于多值函数算子现象学方法的磁滞理论为基础,结合对致动器系统的动力学特性分析,建立了包含磁滞损耗特性的位移模型。结果表明,模型可较准确描述磁致伸缩驱动构件的位移幅值及频率特性,位移预测平均相对误差约为5.6%;系统一阶谐振频率和位移峰值分别为380 Hz和50μm。研究结果为改善喷射系统性能提供一种新方法。

Aiming at the problem that non stepless control and spray quantity being difficult to be accurately minimized which exist in traditional engine injection system,a new magnetostrictive injection system was presented in this paper. It used a giant magnetostrictive actuator to drive nozzle needle directly in order to control the fuel injection process. Opening size and injection quantity of injector were controlled smoothly and rapidly by adjusting the deformation of magnetostrictive materials. On the basis of a hysteresis theory which is based on phenomenological method of multi valued function operator,and combining with the dynamic characteristics analysis of actuator system,a displacement model containing hysteresis loss characteristics was established. Results show that the model can describe the amplitude and frequency of displacement for giant magnetostrictive actuator well. Average relative error of displacement prediction is about 5.6%. The first order resonant frequency and peak value of displacement are about 380 Hz and 50 μm respectively. Research results will provide a new method for improving the performance of injection system.