Based Intelligent Pid Electrode Wire Constant Speed, Constant Tension Control System

The constant speed and tension control problem of wire electrode is the main obstacle to further development of low speed wire electrical discharge machine. Currently, domestic production enterprises usually adopt traditional PID control to achieve the wire electrode maintain constant speed and tension. With the increasing complexity of machining environment and more and more uncertain interference factors, a higher request is set in control system's anti-interference ability and robustness. Though traditional PID control is an useful control mode, both of its anti-interference ability and robustness are still relatively lack of superiority. In view of this, the author combines intelligent algorithms with traditional PID control mode applied to the constant speed and tension control system of wire electrode.In the process of studying the constant speed and tension intelligent PID control system of wire electrode, the following aspects were mainly completed: Firstly, design idea and feasible design project were put forward for constant speed and tension intelligent PID control system, the mathematical models were established for the constant speed and tension control system of low speed wire electrical discharge machine, the selecting of the important hardwares was completed by the technical requirements of the control system. Secondly, fuzzy PID algorithm and BP neural network PID algorithm were designed for the constant speed and tension control system of wire electrode. Fuzziness of inputs and outputs, setting-up and reasoning processes of fuzzy control rules and certainty of outputs were accomplished in the designing of fuzzy PID algorithm. The on-line adjustment expression of hidden layer and output layer, the structure of BP neural network, learning efficiency, inertial coefficient, expected error were determined in the designing of BP neural network PID algorithm. Once more, the simulation analysis of the constant speed and tension intelligent PID control system of wire electrode was completed, including stability analysis, dynamic performance analysis, anti-interference ability analysis and robustness analysis. Finally, the C8051F310 singlechip of Xinhualong Electronics Co. Ltd was used as the controller of the intelligent PID control system and the designs of external hardwares and softwares were carried off.The results show that constant speed and tension intelligent PID control system of wire electrode not only has fast response, small overshoot, small steady-state error, but also has strong anti-interference ability and good robustness. It is indeed a feasible way to adopt the intelligent PID algorithms in the constant speed and tension control system of wire electrode, which also provide a good reference for other control systems.