Hydraulic Synchronous Lifting Control Based On Non-singular Terminal Sliding Mode

With the continuous expansion and development of human exploration of marine resources in recent years,the scope of maritime cargo transportation has gradually expanded,the volume of ships has gradually increased,and the overall development trend of ocean-going and deep-sea development,sea rescue and shipwreck salvage are facing brand-new technical challenges.In order to adapt to the large-depth and large-tonnage shipwreck salvage projects in recent years,the use of cluster hydraulic synchronous lifting technology has become more and more common.However,this technology has exposed some shortcomings in actual engineering use.When the sea conditions are more complicated or high external disturbances,It is difficult for the device to meet the monitoring performance and synchronization performance monitoring requirements using traditional monitoring methods.This article mainly focuses on the research of the control strategy and control algorithm of the four hydraulic cylinder synchronous lifting device.(1)The mechanical structure and hydraulic system of the hydraulic synchronous lifting device are designed,and the lifting process of the lifting device is explained.The proportional reversing valve control cylinder system is mathematically modeled,and the displacement transfer function of the piston rod to the valve core is calculated;the overall simulation model of the hydraulic lifting system is established based on the AMESim-Simulink joint simulation platform,and the identification module in Matlab is used to The model is used for system identification,which lays the foundation for the subsequent controller design of the control algorithm.(2)To summarize and analyze the factors affecting synchronization accuracy during the salvage of the sunken ship;The coupling synchronization control strategy is selected,the characteristics of the deviation coupling synchronization control and the adjacent cross coupling synchronization control strategy are analyzed,and an improved coupling synchronization control strategy is proposed on this basis.The simulation research is carried out through the AMESim-Simulink joint simulation platform to verify the correctness of this control strategy.(3)In order to improve the tracking accuracy of the lifting cylinder,the control algorithm of the lifting cylinder is researched on the basis of the improved coupling synchronization control strategy.Aiming at the complicated working environment of salvaging a sunken ship,sliding mode variable structure control and auto disturbance rejection control algorithms are selected for research and analysis.The principles of sliding mode control and active disturbance rejection control are introduced,and the controller is designed.Finally,the tracking progress and synchronization accuracy of the lifting cylinder under the two algorithms are analyzed through the joint simulation platform.(4)To further improve the control performance of the synchronous machine,On the basis of sliding mode variable structure control,non-singular terminal sliding mode control is introduced.The system state movement point can reach the equilibrium point within the effective time;and the state observer in the active disturbance rejection control is introduced to observe and compensate for the external disturbance that cannot be measured in the system;finally,the system tracking performance and synchronization are analyzed through co-simulation Compared with the simulation results of the sliding mode variable structure control algorithm mentioned above,it shows that the algorithm has better tracking accuracy and anti-disturbance ability.