基于PLC的食品烘干箱温度控制系统设计与试验  

Design and Experiment of Temperature Control System of Food Drying Box Based on PLC

作　　者：张可欣 李成军 陈忠加[1] 袁湘月[1] ZHANG Ke-xin;LI Cheng-jun;CHEN Zhong-jia;YUAN Xiang-yue(The School of Technology,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学工学院,北京100083

出　　处：《保鲜与加工》2022年第6期35-43,52,共10页Storage and Process

基　　金：国家自然科学基金(31500478)。

摘　　要：对粮食或食品进行烘干处理有利于运输、储存与后续加工,而在干燥过程中对温度的控制非常重要。为对比不同算法在温度控制方面的差异,使用西门子S7-200 SMART可编程逻辑控制器(Programmable logic controller,PLC)进行程序设计,并采用昆仑通态触摸屏实现人机交互。同时,为达到提高温度控制精度的目的,通过对传统比例-积分-微分(Proportion-integral-derivative,PID)控制算法与模糊控制算法进行改进,设计了模糊PID复合控制算法和模糊PID切换控制算法。采用梯形图语言对上述4种控制算法进行编程,并进行PLC控制烘干箱的试验验证。结果表明,新设计的模糊PID复合控制算法和模糊PID切换控制算法均在一定程度上反映了其结合要素各自的优点,能有效克服传统PID控制算法动态特性差和模糊控制算法稳态特性差的缺点。当温度由30℃升至设定温度72℃时,与模糊PID切换控制算法相比,模糊PID复合控制算法能将调节时间缩短6 s,且稳态误差减小0.1℃。Drying grain or other food is conducive to transportation, storage and subsequent processing, and temperature control is the most important in drying process. The Siemens S7-200 SMART programmable logic controller(PLC) was employed for program design, and Kunlun touch screen was used to realize human-computer interaction, in order to compare the differences of different algorithms in temperature control. At the same time, in order to achieve the purpose of improving temperature control accuracy, the fuzzy proportion-integration-derivative(PID) compound control algorithm and fuzzy PID switching control algorithm were designed by improving the traditional PID control algorithm and fuzzy control algorithm. Ladder diagram language was used to program the above-mentioned four control algorithms and the experiment verification of PLC controlled food drying box was carried out. Results showed that the newly designed fuzzy PID compound control algorithm and fuzzy PID switching control algorithm both reflected the advantages of their combined elements to a certain extent and could effectively overcome the disadvantages of poor dynamic characteristics of traditional PID control algorithm and poor steady-state characteristics of fuzzy control algorithm. When the temperature raised from 30 ℃ to 72 ℃, the fuzzy PID compound control algorithm could shorten the adjustment time by 6 s and reduce the steady-state error by 0.1 ℃compared with the fuzzy PID switching control algorithm.

关 键 词：可编程逻辑控制器 烘干箱温度控制 PID控制算法 模糊控制算法 

分 类 号：TS205[轻工技术与工程—食品科学]