Research Of CNC Machine Tools Servo System Performance

In recent decades, manufacturing industry has undergone enormous changes with the rapid development of science and technology as well as the economy. CNC machines directly reflect the level of a country’s manufacturing industry, because of which are not only an important support for modern manufacturing industry, but also the core content of advanced manufacturing technology. As an important part of CNC machines, servo system affects and determines the rapidity, accuracy and stability of CNC system.Firstly, analyze the complete mechatronics servo system control model, combined with the basic characteristics of mechatronics servo system, the order of the complete model of mechatronics servo system has been simplified to four, then obtain the general servo controller parameter tuning method which is not depended on the mechanical transmission part parameters by studying the simplified model parameter relationships. The reasonability of the simplified model method and the correctness of the parameter tuning method have been proved by comparing the output differences of position between the complete model and the simplified model of mechatronics servo system. Secondly, the PID, PDF and PDFF control strategies are applied to the speed loop and design methods of the three controllers are given based on the simplified model, and then contrast the three controllers on tracking performance, stability and robustness of the speed loop through the simulation results in MATLAB. In the end, design the hardware and software systems of the servo system, including the TMS320F28335 minimum system, phase current sampling, bus voltage sampling, and isolation and protection circuit and so on.Performance tests of the three controllers have been done on 28335-based servo drive platform, and collect the experiment data, which need to be analyzed in MATLAB, through the upper computer. We can obtain that the theoretical and experimental results are basically the same. In the end of this paper summary and prospect of the work that has been done are shown as well as the follow-up work.