Multiple Resistance Furnace Temperature Intelligent Control System Design

The resistance stove is a frequently-used electric heating equipment in the industrialproduction. Its temperature control is a nonlinear time-varying system which has thecharacteristics of great inertial, pure time-delay. So it is difficult to establish its accuratemathematical model and confirm parameters. We can’t achieve the heating technical requirementfor stable, accurate and rapid adjustment using the traditional PID control. It has greatapplication value to design a resistance stove temperature control system which has high controlprecision and steady operation.With the improvement of industry technology, especially the rapid growth of intelligentcontrol theory and computer control technology, the research of temperature control system hasmade a great breakthrough, and appears some advanced control method, for example, intelligentPID, self-adaptive control and fuzzy control etc. The temperature controller offers bettercontrolling precision and effect, and can be widely applied in the temperature control system andtechnology reformation of relevant devices, and can satisfy the requirement forhigh-performance in the industrial production.This thesis based on the requirement of temperature control in the practical productionprocess of resistance stove, proposed an intelligent control scheme combined thetemperature-current double closed loop control with fuzzy control. It regarded PLC as the centralcontroller, and assisted by Pulse Width Modulation (PWM) technique and bi-directional thyristorpower regulating and other advanced control methods. The system made full use of thecharacteristics of fuzzy controller, and the convenience of PLC programming and maintenance,and the strong anti-interference ability. Compared with the traditional PID controller, it improvedthe precision and stability of the temperature control system. At the same time, according to thetechnical requirement of several resistance stoves temperature control, considered the balancingproblem of transformer terminal loads, designed an intelligent group control strategy ofresistance stoves’ temperature, to achieve the goals of fast response, less overshoot, smallsteady-state error, and simulated with the MATLAB. The results of simulation and applicationshow that the control plan is reasonable, the control arithmetic is available, the dynamic andstatic characteristic of the system is improved further and the anticipated goal has achieved.