Research On Speed Measurement And Control Method Of Variable Speed Hydraulic Pump Motor Control System

The development of motor frequency control technology has led to the birth of variable frequency hydraulic technology.Variable speed pump-control motor hydraulic system make full use of motor frequency control technology,through the technology to change the motor speed,thus it changes the gear pump speed,and the gear pump displacement is constant,so the hydraulic system flow changes,as the hydraulic motor displacement is not change,so it's speed changes with the flow changing,in order to achieve the motor speed control.Although the variable speed hydraulic speed-control system has the advantages of simple structure,low noise,large speed range and energy saving,the slow time-varying characteristics of the system,and poor low speed stability of the hydraulic pump,result in poor system stability,low response speed,low speed accuracy problems and other issues.Therefore,in view of the shortcomings of the variable speed hydraulic speed-control system,from the point of view of the control method,the control quality of the hydraulic motor speed is controlled by two different methods,classical PID control and fuzzy control.In this paper,the monitor and control of hydraulic motor speed are researched under different conditions based on the variable speed pump-control motor hydraulic system through two different methods,classical PID control and fuzzy control.The results show that the classical PID control and fuzzy control can effectively control the motor speed,and the system has good dynamic response characteristics,but the fuzzy control has better robustness.The main studies of the text are as follows:(1)The variable speed hydraulic system platform is introduced in detail,and the test and control of motor speed are explained.(2)The mathematical model of hydraulic system subsystem and the global model of the variable speed pump-control motor hydraulic system are established,the AMEsim and simulink simulations are used to simulate the hydraulic motor speed under the classical PID control and fuzzy control respectively,and the simulation results are analyzed And evaluation.(3)The hardware and software parts of the experimental system of variable speed pump-control motor hydraulic system are introduced in detail,and the programs of measurement and control system are written by LabVIEW software.(4)The test and control experiments of the hydraulic motor speed are conducted based on the built variable speed pump-control motor hydraulic system,and the dynamic response characteristics and robustness of the system under two kinds of control algorithms are analyzed and evaluated.