Design And Characteristics Research Of Solenoid Valve For Electronic Controlled Injector Of Marine High-power And High-speed Diesel Engine

High speed solenoid valve is a key component of electronic control fuel system of diesel engine,which is the terminal actuator to control fuel injection.The static strong electromagnetic force output and fast response characteristics of the solenoid valve provide guarantee for the precise control and flexible adjustment of the fuel injection timing,fuel injection quantity and fuel injection law.Therefore,the modeling and simulation of the solenoid valve and the in-depth study of the influence of various parameters on its static and dynamic characteristics can provide reference for the design and optimization of the solenoid valve of EFI system.In this paper,according to the performance requirements and internal space of a certain injector,the structure of the solenoid valve is selected as E-disc type.The equivalent magnetic circuit method and empirical formula are used to complete the calculation of the relevant size parameters,and the initial design scheme of the solenoid valve is obtained.The static simulation model of solenoid valve is established by using electromagnetic field finite element analysis software,and the accuracy of the model is verified by experimental data.Combined with design of experiment and sensitivity analysis method,the influence of six design parameters on static electromagnetic force is quantitatively analyzed.Then the influence of the key parameters on the magnetic field and electromagnetic force of the solenoid valve is analyzed in detail.The sub-models of magnetic field,circuit and mechanical motion are built respectively,and the transient co-simulation model of solenoid valve is obtained by combining them.The effects of peak current,armature thickness,spring preload and residual air gap on dynamic characteristics are analyzed.It is found that more than 90% of the electric energy input into the system is converted into Joule loss and eddy current loss by studying the energy conversion relationship of the solenoid valve in one working cycle.Due to the solid structure of the iron core,the eddy current effect is more significant and concentrated in the lifting and reset stage,and the eddy current seriously hinders the magnetization and demagnetization process of soft magnetic materials,resulting in the prolonged response time of the solenoid valve.After the improvement of the iron core structure,the eddy current loss is reduced to a certain extent,and the response characteristics of the solenoid valve are effectively improved.With the help of surrogate model technology,the surrogate model of high-speed solenoid valve is established.Based on this,a multi-objective optimization model was established with the response time of pull-in and release as the optimization objective,the difference between electromagnetic force and spring preload,Joule loss and the design variables as constraints.After optimization,the response time of the solenoid valve is slightly shortened.