Optimization The Performance Of PWM High Speed Digital Valve Research Based On Fuel Injection System

With the development of increasingly stringent of emission regulations and electro-hydraulic control digital technology,the fuel injection common rail system has become one of the trends in the development of diesel engine systems under complex injection requirements.As the important method to realize the integration of electro-mechanical equipment and digital control technology,electro-hydraulic digital technology is an ideal method for rapid and precise control of fluid transmission and control system.Has been widely used in automobile,machanical,aerospace and other control areas.The High-speed digital om-off valve as a digital control electro-hydraulic system is an important factor because it is to achieve the system of digital control of the key components,the working principle is based on a series of pulse signals to electromagnet magnetization of electronic control to produce magnetic force,so that the digital switch valve valve port in the open and close between the two types of fast switching to achieve the oil through the cycle.High speed digital on-off valve response speed as the research target of this topic,with two two-way valve as the basic structure,to reasearch & develop a "pulse width reversal" type high speed digital on-off valve.Arround the issue how to improve the response frequency of the digital on-off valve,using the the principle of magnet opposites attract and poles repel,optimize the digital valve structure,to achieve the purpose of high frequency response.And then according to the simulation software Fluent and AMESim to test the static and dynamic characteristics of the valve.Firstly,this paper based on a fuel injection electronic control digital on-off valve design theory,talking full account of the frequency response characteristics,proposed a "pulse width reverser" type high-speed digital switch valve.Then the working principle of PWM high-speed digital switch valve is introduced,and the mathematical model of the valve core movement is established.Through analysis,preliminary model valve of high-speed digital switch valve is successfully developed.Secondly,according to the expected target of the initially design and calculate of the structural parameters,the flow field of the valve opening of the designed and analyzed by Fluent simulation software,obtained velocity flow field,pressure field,density field,turbulent kinetic energy vector when the spool moving.Finally,this article uses AMESim simulation software to simulate the dynamics of “pulse width reverser”type digital on-off valve,and through the comparison with the dynamicsimulation of the spring reset digital on-off valve,highlight the rapidity of the former response to verify the feasibility of the design,provide theoretical support for the next step.