基于线性自抗扰控制的高频真空感应炉温度控制

真空感应炉是对金属材料进行热处理工艺的一种高效设备。在感应加热系统中,温度的高低直接影响着加热物料的质量好坏。而如何实现加热温度的精确控制,是控制系统需要解决的关键问题。目前,大部分的温度系统仍使用PID控制方法,但PID控制中的控制参数一旦确定就只能适应一个系统,这就导致了该方法具有较差的抗干扰能力,影响了系统的控制精度以及控制速度。为了改善上述PID控制的缺点,通过在真空感应炉上进行数据采集,并应用MATLAB对系统进行辨识,提出了真空感应炉的温度控制系统的线性自抗扰控制策略。设计了用来对系统的状态及总扰动进行实时观测并给予补偿的线性扩张状态观测器,求取控制器参数的收敛范围,应用劳斯判据对系统的稳定性进行分析。最后,应用MATLAB进行设定值跟踪和抗干扰能力仿真,仿真结果表明:LADRC比传统的PID控制系统具有更快的响应速度以及控制精度,且鲁棒性更优。

Temperature control of high frequency vacuum induction furnace based on LADRC

The vacuum induction furnace is an efficient equipment for heat treatment of metal material.In induction heating system,the temperature of heating material directly affects the quality of heating material.The way to realize the accurate control of heating temperature is the key problem to be solved in the control system.At present,most temperature systems still use PID control method,but one single system can be adapted once the control parameters in PID control have been determined,which leads to poor anti-interference ability,affecting the system control precision and control speed.In order to improve the shortcomings of PID control,through the vacuum induction furnace data collection,the MATLAB has been used to identify the system.The linear active disturbance rejection control(LADRC)strategy of temperature control system for vacuum induction furnace has been proposed.The Linear Extended State observer has been designed to observe and compensate the state and total disturbance of the system in real time.The convergence range of controller parameters has been obtained and the stability of the system has been analyzed by use of Routh criterion.Finally,MATLAB has been used for setting value tracking and anti-interference ability simulation.The simulation results show that the LADRC system has faster response speed,better control accuracy and better robustness than the traditional PID control system.