Development And Research On Dynamic Characteristics Of Water Hydraulic Control Valve Directly Driven By Voice Coil Motor

In the field of electro-hydraulic control,electro-hydraulic servo valves and proportional valves are widely used.For a long times proportional valves and servo valves have mostly been two-level or even three-level structures,and use high-performance servo valves as their pilot stage,forming a two-stage or even three-stage structure,which makes the valve structure complicated,the cost is high and rarely used in the field of pure water hydraulics.In recent years,the application of linear motors has become more and more extensive,and the servo control system for linear motors has also made great progress.In the electro-hydraulic control system,compared with traditional electro-mechanical converters such as proportional electromagnets and moving coil motors,voice coil motor(VCM)has the advantages of faster response,greater output force,and lower cost.The closed-loop controller of VCM has many types and convenient selection,so it is widely regarded as an excellent electro-mechanical converter.Based on the VCM direct-drive water-hydraulic control valve developed by Wuhan Peng Senior,this paper improves the structure of the direct-drive valve,established a dynamic mathematical model of the valve,and conductes experimental research.The main content of the paper is summarized as follows:Chapter 1,Describes the research background and significance,and introduces the domestic and foreign research status of direct-drive electro-hydraulic proportional/servo valve,VCM direct-drive valve and its dynamic characteristics,voice coil motor and its advanced control and forces acted on spool,lead to the main research content of this article.Chapter 2,The design and working principle of the overall structure of the direct-drive valve are explained,and an improved plan is proposed;based on the force relationship on the spool,the VCM and the valve body are studied separately,and the mathematical model of the VCM and the spool are established respectively kinetic model.Chapter 3,A complete model of the direct-drive valve was established in Simulink.In order to identify the key coefficients in the model,a spool friction measurement test bench and a VCM test bench with elastic load were designed and built.And the damping coefficient of the VCM was identified;finally,the open loop dynamic characteristics of the direct drive valve were simulated and studied.Chapter 4,The VCM direct-drive valve was tested.Firstly the direct-drive valve test bench and conduct open loop test research is introduced;secondly the PID control model of the direct drive water hydraulic valve of the voice coil motor is established in Simulink,the best PID control parameters is calculated and determined;and finally established a PID control system of the direct-drive water hydraulic valve of the voice coil motor and the closed loop test research of the direct drive valve are carried out.Chapter 5,The main research work of this paper is summarized,the shortcomings of the research in this paper are analyzed,and the follow-up work is prospected.