Research On Temperature Tracking Control System Of Electric Heating Furnace

The electric heating furnace is a typical heat treatment equipment in the industrial production process,and its temperature control effect directly affects the safety of the production process and the quality of the product.The temperature control process has the characteristics of nonlinear,large inertia,capacity delay,etc.Therefore,analyzing and studying the control algorithm and its improvement methods have important reference value for the steady and efficient operation of the heat treatment production process.Regarding the temperature control of the electric heating furnace,based on the SX₂-1200 electric heating furnace,the following researches are mainly done:First,the basic working principle of the electric heating furnace is analyzed and studied,referring to the technical indicators and control system structure of the original typeⅢmeter control system,the plan of the control system based on S7-300 PLC is designed,and the construction of the experimental device is completed.Secondly,the PID algorithm of the traditional control system is researched,the temperature PID control program,the temperature segmental setting tracking program and the human machine operation interface program are compiled,and the experimental tests are carried out.In addition,according to the experimental data of the electric heating furnace,the black-box method is used to identify and establish the mathematical model of the differential equation of the heating process of the electric heating furnace,the model is digitized through the difference method,the simulation program of the model is compiled by using the scripting language of the Win CC configuration software,and the simulation results are compared with the actual results to verify the accuracy of the system identification.Finally,the research is mainly focus on the improvement of the nonlinear PID control algorithm,and the improved temperature control program of the electric heating furnace is compiled in the STEP7 industrial control software,and the improved control effect is compared and analyzed with the original temperature control instrument and the effect of the traditional PID control algorithm.The operation and test results show that the improved nonlinear PID temperature control algorithm has achieved excellent tracking control effects,and has reached and exceeded the expected requirements in terms of overshoot,transient time,steady-state error,and other indicators.Through the human machine interface,the temperature rise curve can be easily set and the actual temperature trend data can be displayed in real time,which has achieved that the furnace temperature can quickly and accurately follows the set value.The system is more convenient to operate,stable in operation,safe and efficient,and has strong anti-disturbance ability,which greatly improves the efficiency of the equipment production.