Design And Research On Hydraulic Control System For Berth Car

Berth car is an important equipment in shipping industry.The Lift cylinder and roll oil cylinder are heavily burdened when this equipment is working.Besides,there are a high requirement in the displacement of piston rod of hydraulic cylinder,precision of the speed of the hydraulic cylinder piston rod and the synchronous control accuracy of the berth car.In order to meet the actual needs of production and ensure the stable operation of the equipment,the berth car hydraulic control system is designed and researched.Deduct and analyze the system stability based on the mathematical model of berth car closed-loop position control system.Model and make simulation research of berth car closed-loop position control system and berth car synchronous control system by using the simulation software.The paper introduces the research background,purpose and main content,and describes the basic composition and working principle of berth car.The research identifies the technical scheme of the berth car hydraulic control system according to the technical specifications and working process requirements.Making cylinder realize the closed-loop position control system by using servo proportional valve and displacement sensor,and select the hydraulic components.The mathematical model of the berth car servo valve controlling the hydraulic cylinder position closed-loop system is established,and transfer function of each link in the system is also deducted.Besides,the open loop transfer bode function diagram should be depicted according to the transfer function block diagram.On this basis,the control system stability of the lateral movement berth car lifting oil cylinder and the cylinder is analyzed under different working conditions.The servo proportional valve simulation model is established based on AMESim simulation softwares,and its dynamic and static characteristics should be analyzed to match the sample curve.The simulation model of the servo proportional valve is added to the simulation model of the berth car’s system,and the dynamic response simulation model of the whole closed-loop position control system is established.The synchronization control of the berth car is realized by using the main control method which is widely used in the production,and the simulation model of the synchronous system is established.After the dynamic characteristics and the error characteristics of a closed-loop position control system have been analyzed and researched,and so have the control characteristics and the error characteristics of the synchronization system.It is found that the performance indexes did not meet the requirements of the system and need to make some adjustment to this two system.Considering the convenience of the operation in practical production,the PID correction link is joined and better PID control parameters can be obtained.The results show that the dynamic performance index such as displacement and velocity of the berth car closed-loop position control system,and the berth car control system synchronization precision can satisfy the system requirements after adding the system correction.