Research On Stability Control Of High Precision Hydraulic Pumping Station For Graphite Film Preparation

Graphite film is a kind of polymer compound film with carbon as its main component.It is a new type of heat conduction and heat dissipation material.It is widely used in electronic products such as televisions,digital cameras,mobile phones and computers.The preparation process of the graphite film includes a calendaring process.The main device used in the process is a calendar.Since the thickness of the graphite film product directly affects the effect of heat conduction and heat dissipation,the calendaring accuracy of the calendar is critical.The core is the hydraulic system in the calendar.At present,the hydraulic systems used by the graphite film manufacturers at domestic and abroad in the calendaring process are mainly hydraulic AGC(Automatic Gauge Control)system and high-precision hydraulic pumping station system.Among them,the research of hydraulic AGC system is relatively mature and the fields of application are also compared.A wide range of high-precision hydraulic pumping station systems,due to their semi-closed-loop control properties,have certain inherent shortcomings compared to the closed-loop control of the AGC system.However,the high-precision hydraulic pumping station system has just emerged,there is still a lot of space for optimization of its overall performance.Its structure is simple and the cost is low as well.Therefore,this paper will use scientific modeling,computer simulation and prototype experiments to improve the performance of high precision hydraulic pumping station system.Firstly,the main hydraulic components in the high-precision hydraulic pumping station system are designed and selected.The secondary hydraulic components are adapted and selected.The physical model of the hydraulic system is initially built.In this paper,the functional design and power check of the electric hydraulic pump are carried out.The parameter design and model selection of the capsule accumulator are carried out by the "extreme value method".The remaining hydraulic components are determined by port matching or pressure flow matching.The preliminary construction of the physical model of the hydraulic system provides a reference basis for subsequent research.Secondly,I will analyze the various working stages of the high-precision hydraulic pumping station,abstract three representative workflows from it.I will use the “power bonding diagram” to perform logic analysis on the power flow for these three workflows according to the power key.The figure shows the state equation of the hydraulic system,gives the calculation equation of the relevant variables,and the specific values of the relevant constants.Then the mathematical model construction of the high-precision hydraulic pumping station system is completed.Then,with the multi-disciplinary comprehensive simulation software AMESim,the high-precision hydraulic pumping station system is studied.The four factors of structural layout,control program,accumulator nitrogen filling pressure and throttle opening size are studied.Subdivided the three horizontal states for comparative study,taking the two parameters of system pressure holding time and pressure holding accuracy as the object of investigation,using the scientific experiment method of orthogonal experiment,the three representative workflows mentioned was carried out separately.Finally several sets of optimal simulation schemes were obtained.Finally,the simulation scheme is verified by the physical prototype to verify whether the optimization scheme given by the computer simulation can further improve the working performance of the high-precision hydraulic pump station system on the basis of the original.At the same time,through the research in this paper,the final set of optimization schemes has been officially used in the improved high-precision hydraulic pumping station of a foreign company in January 2019.The performance of the hydraulic pumping station has been greatly improved under the condition of original manufacturing cost.It has got the improvement of product quality and the growth of benefits for enterprises.