Energy Saving Control Research Based On The Vector Control Of Pump And Valve Cooperate System

Electro hydraulic servo system is a classical system of Pump Valve Co controlled hydraulic cylinder.It is widely used in the field of high precision control machinery,such as numerical control machine tool,forging machine,ship machine,etc..But the common electro-hydraulic servo system has many problems,such as low utilization ratio of energy and serious pollution of oil source.As for the traditional pump control system of volume displacement,it has high energy saving,but the defect of low control precision makes it unable to be used in the project.Therefore,in order to solve the problem that the pump control efficiency and energy saving of the electro-hydraulic servo system are not compatible with the fast response of the valve control and the high precision of control,a pump valve co control system of the pump control unit with real-time variable frequency control is designed.Firstly,the model of energy conservation control system of pump valve is analyzed,then the performance of pump control loop and valve control loop is analyzed,and the corresponding PID controller is designed to improve the system performance.Through the vector control scheme of frequency converter,the pump control loop based on variable frequency speed regulation is designed.At the same time,the fuzzy PID control algorithm is used to adjust the speed of the motor smoothly and quickly.Since the position of hydraulic cylinder in the valve control loop is interfered by the external signal,a feedforward compensation PID control algorithm is designed to compensate the displacement of the hydraulic cylinder before disturbance.To establish the model of accumulator,to meet the stability of the pump control system,verify the feasibility of adjusting the motor speed through the change of the pressure at the pump port,and analyze the performance of the accumulator.The selection scheme of accumulator is determined.Through the joint simulation of AMEsim and Simulink,the model analysis of frequency conversion motor directly affects the realization of the designed servo system.Therefore,the parameters of the motor are changed,and the performance of the motor is adjusted.Set up and then AMEsim design of pump system energy saving inverter control based on the model,to achieve the requirements of pump control fuzzy PID controller and feedforward compensation controller PID valve control function through the software module programmed in Simulink,the cosimulation of serial communication.The new valve association through the analysis and comparison of design of control system in electric hydraulic proportional servo system better in traditional oil source part of energy saving,but also because of the design of control strategy can enhance the response speed,higher control precision,and verify the validity of the control strategy.