Research On Hydraulic Synchronous And Positioning Control System For Shield Machine Support

The shield machine is a common construction machine which is used in construction for subway tunnels and highway culvert.The Shield machine support operation is an essential link of construction,and the accuracy of synchronous and positioning control for support cylinders play a vital role in the overall construction quality.Therefore,it has become a research emphasis how to improve the control accuracy of the support cylinders on the premise of ensuring construction safety in this field.Aiming at the problem of the synchronous and positioning control for the steel arch mounter horizontal cylinders,the paper combines the electro-hydraulic servo proportional technology with the master-slave synchronous control strategy to study the overall control principle in the system.It uses the math tool of the Laplace transform to establish the mathematical model of the control system and deduct the transfer function,analyzing the stability by using the Bode criteria.The paper builds the control system simulation model based on the AMESim multi-disciplinary complex system modeling and simulation platform,and analyzes the dynamic characteristics,positioning and synchronous tracking errors.According to the actual PLC control mode,the paper further studies the PID control strategy under the discrete conditions,and adopt optimized PID control parameters to correct discrete systems and obtain the best control mode in the system.In order to meet the requirements of energy saving and environmental protection,the paper improves the hydraulic system by using constant pressure pump and accumulator.Aiming at the influence of the displacement of the fixed pressure pump,the volume and the inflatable pressure of the accumulator,the paper studies the energy saving effects by utilizing the AMESim simulation software,and obtains the better control parameters.The results in the two-cylinder hydraulic control system of the shield machine support operation show that the combination of master-slave synchronous control strategy and PID control system can achieve the control requirements in terms of the response speed and the control accuracy.The use of the fixed pressure variable displacement pump and the accumulator is effective in improving the energy utilization rate of the system,and the energy saving effect can be significantly increased by 70%,compared with the fixed pressure variable displacement pump and the relief valve system.The above conclusions which provide a reference direction for research in the related fields.