Research On The Design And Synchronous Control Of The Directional Movement System Of The Captain Of The Catamaran Crane

With the rapid development of the global economy,the demand for traditional energy sources such as oil and gas continues to increase.Land resources are no longer sufficient to meet the growing demand for sustained profit growth.To meet energy needs,countries are increasing their investment in offshore oil exploration and extraction.Offshore lifting systems play a crucial role in offshore oil exploration and extraction and are gradually moving towards larger and more integrated systems.However,as offshore development activities increase,the need for sustainable operations and mitigating environmental impacts becomes more urgent,posing significant challenges in handling decommissioned offshore platforms.Dual-body vessel lifting systems have become an effective solution for the installation and removal of large offshore platforms,aiming to reduce manual and environmental risks.They are also expected to reshape the industry landscape for the installation and decommissioning of large offshore platforms and set new standards for the marine industry.This paper focuses on the longitudinal movement system of the dual-body vessel lifting crane and conducts research on the supporting structure and multi-motor synchronous control issues within the movement system.Firstly,the requirements analysis and design of the longitudinal movement system of the dual-body vessel lifting crane were conducted based on user demands.The structure design of the movement system,including the design of the supporting structure and transmission chain,was carried out according to relevant mechanical design standards and industry regulations.Secondly,a finite element model of the supporting structure was established in ANSYS Workbench,and mechanical analysis of the structure was performed,including static analysis,modal analysis,and harmonic response analysis.The static and dynamic characteristics of the structure were obtained,providing references and guidance for the design optimization of the structure.Next,addressing the issue of multi-motor synchronous control in the longitudinal movement system of the dual-body vessel lifting crane,a mathematical model of the permanent magnet synchronous motor was first established,and an analysis of vector control for the permanent magnet synchronous motor was conducted.Then,an adaptive sliding mode control algorithm based on ring coupling control strategy was proposed.The speed controller for the multi-motor system was designed,and the stability of the controller was proven based on Lyapunov stability theory.Finally,simulation comparative analysis of conventional PI control,sliding mode control,and adaptive sliding mode control was conducted in the Matlab/Simulink module,demonstrating the effectiveness of the proposed control method.Lastly,addressing the problem of difficult torque estimation in the multi-motor system,a multi-motor synchronous control method based on global fast terminal sliding mode control was proposed.The principles of the global fast terminal sliding mode control method were introduced,followed by the design of the speed controller for the multi-motor system,and the stability of the controller was proven based on Lyapunov stability theory.In addition,a robust observer for torque estimation was designed to effectively suppress the influence of external disturbances and uncertainties in system parameters on the dynamic characteristics of the system.Simulation comparative experiments were conducted in Matlab/Simulink to validate the superiority of the proposed control method.