基于PLC的微波加热器温度控制系统设计

Design of Temperature Control System for Microwave Heater Based on PLC

设计了一套PLC控制的微波加热器温度控制系统。以工业高功率微波加热器为研究对象,用S7-200PLC及模拟量输入、输出模块组成基本控制单元,使加热器内温度保持恒定。针对微波加热器内温度系统的大惯性、非线性特征,采用模糊控制算法来对温度进行处理,克服了传统PID算法参数调整复杂、超调量大的缺点。实验结果表明,对温度采用模糊控制能获得较好的稳态精度和动态特性,能够满足工业领域恒温加热的要求。

This paper introduces a kind of temperature control system of microwave heater controlled by PLC. The high power microwave heater for industry use is taken as the object and the basic control unit composed of S7-200PLC and the input and output modules of the analog volume is used to maintain the temperature constant in the heaters. Aiming at the feature of non linearityand large inertia of temperature system in the microwave heater, the is used to deal with the temperature and overcome the disadvantages of complexity in parameters adjustment and big overshoots of traditional PID. Results show that the fuzzy control used in temperature system can obtain better steady state accuracy and dynamic characteristics, and also satisfy the demands for constant temperature heating in the industrial field.