Research on Sapphire Furnace Temperature Control Strategy based on Active Disturbance Rejection Control

In the process of sapphire production, it needs to control the furnace temperature accurately. Aiming at the modeling of temperature control system of sapphire furnace, this paper adopts the method of increasing order to approximate the timedelay operator to the first-order inertial link, so that the first-order time-delay system can be approximated to the second-order time-delay free system. In order to solve the problems such as poor stability and difficulty in precise temperature control during sapphire growth, an active disturbance rejection control(ADRC) based temperature control strategy is proposed in this paper to realize accurate temperature control. A new type of nonlinear tracking differentiator is used in the construction of ADRC. Respectively using MATLAB to the PID control strategy and ADRC control strategy are simulated. The simulation results show that the ADRC control strategy proposed in this paper has higher control accuracy, no overshot tracking and better disturbance rejection ability.