The Design And Study Of Motion Control System Of Wire Electrical Discharge Machine

"With the development of the die & Mold industry and the Equipment manufacturing, the high-speed Wire Electrical Discharge Machine (HSWEDM) technology has been unable to meet the requirements of industry. Based on the research of Wire Electrical Discharge Technology at home and abroad in this paper, this scheme applies the 16bits CPU controller, with the addition function of LCD display and upper computer partly, making an improvement of the High-speed WEDM System.In the interpolation process, given the shortcomings of conventional point by point comparison method, interpolation feed efficiency is improved with the improved point by point comparison method in the system.The article studies the two kinds of typical CNC system-open-loop systems and closed-loop systems. The paper analyses the character of speed increasing and decreasing and jog control of the stepper motor in the open-loop control system. AC servo motor is used as the controlled object in the closed-loop control system. In view of the friction nonlinearity and uncertain external disturbance in the Bi-axis servo system, on the basis of analyzing the contour error of the system, combined with the idea of cross-coupling, an improved second-order Active Disturbance Rejection Controller (ADRC) is proposed. The inner disturbance and outside disturbance of the system, as well as the friction could be observed and compensated by the extended state observer (ESO) of ADRC, which has strong robustness. Due to applying a new non-linear function to overcome the rough of non-linear function, which leads to the system sensitive to the friction in the nonlinear state error feedback of conventional ADRC, friction compensation could be carried out well. Finally, according to wire cutting model, combined with the actual processing of the circumstances, the simulation experiments are carried out. The simulation results show that the control algorithm achieve the good control effect.The system implements the decoding processing and with the improved feed algorithm to improve the feed in the WEDM of software design. The software completes the requirements of feed automatically. The system provides function of power-off protection and power-on continuing to process. The thesis analyses and realizes the function of wire radius compensation of the HSWEDM machine tool. Compared with the theoretical coordinate, the method is proved precisely by the in actual coordinate the experiment of Wire radius compensation.