Multi-Domain Modeling And Simulation Of CNC Milling Machine Tool Spindle System

With the development of science and technology and the promotion of production technology, the applications of high efficiency and precision machines are more and more widely, so the demands to the processing equipment have become increasingly higher and higher. Spindle system as an important part of CNC machine tool directly affects the performance of CNC machines. Do the research and analysis of the factors that influenced the performance of the spindle which means a lot to improve the dynamic characteristics of spindle system, thus improving the accuracy and efficiency of CNC machine. Since the spindle system as a coupled system is across multiple fields, which will cost a lot both in time and economic if it's entirely by experimental research and analysis. Thus computer modeling and simulation techniques are introduced to study and analyze the problems and establish Multi-domain models of spindle system of CNC milling machine based on Modelica language standards. Do the research and analysis through combining with the simulation results and theories on the dynamic performance of the models, which focused on the following main points:Firstly, Based on the analysis of the underlying physical principles and regular patterns of the spindle system of CNC milling machines, the system was divided into electrical, control and mechanical subsystem, then established mathematical models of asynchronous AC motor and conducted dynamics analysis of the spindle mechanical transmission system. Meanwhile, based on the ideas of modular modeling, the models of asynchronous AC motor and mechanical transmission subsystem were established followed the Modelica language standards.Then, analyzed the control system based on the rotor field oriented vector control and space vector pulse width modulation(SVPWM), the model of drive and control system was established either,then integrated the various subsystems into the overall model of spindle system.Finally, in order to verify the correctness and analyze the performance of the model, then conducted simulation analysis of the asynchronous motor model, asynchronous motor and driver control system integration model and the overall model of spindle system respectively, combined with the simulation results and the theoretical analysis showed that the established models were corrected, while the curves of the system were analyzed which showed the system had good dynamic characteristics as well. What's more, sweeping experiments about some mechanical parameters were designed to study their influence to the dynamic characteristics of the spindle system.The research method has certain significance to enhance the performance of CNC machine, which provides a new idea in order to achieve high-efficient and high-precision CNC machine research.