Research On Permanent Magnet Synchronous Motor Spindle Drive Technology

The electric spindle is the core part of the modern numerical control machine tool, which improves the machining efficiency and quality. The permanent magnet synchronous spindle (PMSS) has the advantages of compact structure, high efficiency, high power density, etc. And its application is an important trend in field of numerical control machine tools. Therefore, it has a great significance to develop a high-end PMSS drive system with exclusive intellectual property rights. The design of PMSS driver, containing software control algorithm and hareware drive system, is studied in this paper.Fristly, the background and significance of the research is explained in this paper, and then a detailed exposition from the development status of the electric spindle with its drive system and the research status of electric spindle drive technology are given.Secondly, based on the structure and the mathematical model of PMSS, the principles of vector control and weakening-flux control are discussed in detail. Then, thev id=0 vector control, the SVPWM control and the weakening-flux control based on the q-axis voltage difference feedback method are designed. The whole PMSS driver system is built up in Matlab/Simulink, and the simulation and analysis of vector control and weakening-flux control is conducted.Thirdly, considering the influence of the defect of the classical PI regulator on the speed-loop, especially in the situation of external load disturbance, the speed tracking performance of PMSS system will be greatly weakened. Therefore, the technology of PMSS velocity perturbation is studied, and a speed-loop ADRC regulator is designed. In this method, the total disturbance of the system is estimated and compensated by using ESO, and nonlinear combination of the errors is done by "NLSEF. The simulation and analysis are conducted, and the result shows that the system with speed-loop ADRC regulator can well suppress external disturbances, and can obtain a better performance than that with PI regulator.Finally, the hardware and software of PMSS driver system based on DSP+CPLD are designed. The design of hardware drive system mainly includes power converter, main control board, main circuit, driver for IGBT, etc. The design of software mainly includes the starting strategy, the vector control algorithm, the weakening-flux control algorithm, PI regulator, etc. The whole PMSS drive system has been tested with a PMSS developed by otheir members of our project and the result shows that the designed PMSS drive system can well work in the whole speed field and have a good robustness, which also proves the correctness and feasibility of the design of PMSS drive system.