Research On Electromechanical Joint Modeling And Simulation Analysis Of Synchronous Control Of Double Screw Drive

The feed system is an important functional component of CNC machine tools,and its position control accuracy is an important factor affecting the machining accuracy and quality of CNC machine tools.The driving mode of dual motors + dual ball screws in parallel arrangement to drive the table movement greatly improves the transmission rigidity of the mechanical transmission structure,but due to the dual motor drive form,there is a synchronization error,which in turn leads to a decrease in the synchronization control accuracy.Therefore,improving the synchronization control accuracy of the servo system is of great significance to improve the stability and accuracy of the dual-drive feed system.This thesis takes the double-screw drive feed system as the research object,and studies the three-loop control parameters of the servo system and the synchronization control strategy that affect the control accuracy.Through theoretical modeling of the double screw drive feed system,the parameter tuning of the three-loop control system was completed,and then the appropriate performance evaluation index was selected to optimize the three-loop control parameters,and finally a suitable synchronous control strategy was selected.Research on electromechanical joint modeling and simulation was carried out.The main research results obtained in this thesis are as follows:(1)The servo control system was analyzed,and the establishment of the three-loop control structure and the mathematical model of the servo motor was completed,which provided a basis for the servo system control parameter tuning in the future.(2)The mathematical model of each link of the three-loop control structure was established,combined with the classical control theory,the establishment of the respective parameter setting formulas of the three-loop control structure was completed,and unknown parameters were identified,and the theoretical values of the three-loop control parameters were obtained.(3)Based on the mathematical model,the servo system control parameter tuning optimization analysis was carried out: the characteristics of various performance evaluation indexes were analyzed and compared,and the theoretical calculation value of the three-loop control parameter was optimized in combination with the coordinate rotation method.The feasibility of the optimization method was verified by the optimal value of the three-loop control parameter and its step response output curve.(4)Combining with the servo control system,the rigid-flexible coupling model of the double-screw drive feed system and the electromechanical co-simulation model was established,and the influence of the master-slave synchronization control strategy and the cross-coupling synchronization control strategy on the performance of the feed unit was analyzed.A better synchronization control strategy was selected based on the simulation results.