Abstract: The space distribution characteristics of large components affect the dynamic response of a feed system, which must be considered in remanufacturing large-scale machine tools. Aiming at a large milling machine, distributed parameter modeling method is used to describe the transfer subsystem of a slender ball screw, and lumped parameter modeling moethod to describe an AC servo subsystem and a worktable drive subsystem, then a distributed-lumped model of a feed system is formed by coupling the three subsystems through rotational speed relations. Comparisons between simulation results and experimental results prove that the distributed-lumped model coincides with the physical system, and the dynamic characteristics of the large machine-tool feed system can be accurately described. The dynamic responses of distributed-lumped model and pure lumped model under different distributed characteristics are discussed, and the results indicate that dynamic response differences between two models will change with the variations of system inertias, which provides a scientific basis for the design and control of large-scale machine tools

Key words: Distributed parameters, Dynamic response, Large-scale machine tool, Remanufacturing