Study On Characteristics And Modeling Of Electro-hydraulic Proportional Valve Controlled Motor System Supplied By Variable Pressure

Recent years,the electro-hydraulic control system,which takes accumulator as the energy storage and oil supplying component,has been preliminary applied in hybrid electric vehicles,energy collection and power system.Different from traditional electro-hydraulic control systems,the imported oil pressure of the system which is supplied by accumulators will decline over time.So it is not a constant value.This phenomenon has additional interference on the load control,especially for electro-hydraulic control system which has a requirement for a constant speed.So firstly an electro-hydraulic valve controlled motor system supplied by variable pressure from accumulators is designed,in which the hydraulic motor need to drive an AC or DC generator with constant speed and power;Secondly the mathematic model of this system is built.Then the corresponding system transfer function is deduced.And the static and dynamic characteristics of the system are analyzed in theory.Thirdly,based on a combination of Matlab / Simulink and AMESim,the simulation models of the studied system are built,which are focused on the simulation analysis of the speed control characteristics.Finally,a novel method with a combination of pressure compensation control and adaptive fuzzy PID control is presented in this paper.Its corresponding control system simulation is completed.The theoretical analysis and simulation results show that the mathematic model and corresponding system transfer function are correct and effective.And the novel method with a combination of pressure compensation control and adaptive fuzzy PID control is better than that of traditional PID control method.