Research On The Operating Device Of Loader Based On Electro-hydraulic Proportional Control

Since the hydraulic transmission technology is applied on the loader,the power matching problem caused by the changeable condition of the vehicle is solved,and the attention is turned to the operating device of the core component of the loader.The efficiency of operating device determines the overall performance to a great extent,how to improve the work efficiency and reduce the intensity,puts higher requirements on control system.As the electromechanical integration technology is widely used in loader,the mainstream of the domestic and foreign products are mainly focused on based on the hydraulic proportion of load sensitive or electro-hydraulic proportional pilot control system.Although the proportional control system has been applied in the loader successfully,the control quality is different due to the different control algorithm adopted by each manufacturer.This paper is based on the project of school-enterprise cooperative ‘the development of loader’(project no.:FW/RD201640),it focused on the problems existing in the operating device of domestic loader,and the corresponding results are applied to the sample vehicle.The system adopts electro-hydraulic proportional control,which can effectively improve the operating experience of the driver and improve the operating efficiency and automation degree of the whole machine,at the same time,it also effectively improves the operating experience of the driver.The characteristics of the system are analyzed comprehensively.and draw a relevant conclusions by the theoretical research,emulation analysis,and prototype testIn the theory research stage,on the basis of consulting a large number of literature,summed up the domestic electric liquid proportion technology present situation and application of the technology on the loader,The principle and composition of electro-hydraulic proportional control system are described in detail.Designed electrohydraulic proportional control system of the loader working device,analyzed the working principle with the concrete action of the loader,at the same time complete component selection of the microcomputer control system and the analysisn of the electric control system.Through the construction of electrohydraulic proportional control system mathematical model,the main components of each link the transfer function of system is deduced and the stability analysis,for subsequent control strategy research and simulation analysis to lay the theoretical foundation.The simulation model of electro-hydraulic proportional control system of loader working device is built through Simulink software platform,the simulation results are analyzed with various control algorithms,by comparing the advantages and disadvantages of various control strategies,the algorithm of fractional order PID is proposed and applied to the system.The simulation results show that,compared with the integer order control algorithm,the fractional PI algorithm is more flexible in the control form and can achieve better control effect.In this paper,the experimental scheme of electro-hydraulic proportional control system for the working device is designed,and the system model obtained by the simulation analysis of the theoretical research is further verified.The experimental results show that the actual performance and theoretical model of the electro-hydraulic proportional control system are consistent.The experimental results have a good effect on the theoretical analysis of the foreword,it is shown that the fractional order PID have a good performance in the electro-hydraulic proportional system of the loader working device,it provides a practical reference value for the application of fractional order PID control algorithm in other engineering vehicle electro-hydraulic proportional control system.