Research On Open Control System

With the development of industrial automation technology, the traditional control system structure can not meet the requirements of modern industrial production. Therefor, more and more engineers and users are concerned about the research of open control system. It improves the reconfigurability and scalability of the control system. Automation of induction heat treatment production line is a typical industrial process control, the traditional method currently used is backward, and the control accuracy is not high, time lag and over control are existing. To solve these problems, this paper designs the control network structure based on CC-Link open field bus, which is applied to the induction heat treatment production line.According to control requirements of induction heat treatment, the system structure is divided into two parts: host computer monitoring system and PLC control system based on CC-Link. The functions of the two parts have been analysed and divided. The whole design proposal and hardware configuration are introduced.Aimed at the response lag of induction heating furnace, variable structure control strategy is proposed by making use of modern control theory. When the induction heating is in the initial state or large deviation from the scope of error precision, using minimum-time control; when the induction heating is in a stable state, using PID control. Then, Matlab simulation is established to verify the control algorithm is effective and feasible.Finally, software design of the PLC system and the host computer monitoring system are completed. System testing result shows that the control system is stable, strong anti-interference, high reliability, and meets the requirements.