基于模糊决策的谷物烘干机温度自动控制仿真

Simulation of Temperature Automatic Control of Grain Dryer Based on Fuzzy Decision

针对当前谷物烘干机温度控制相关方法存在容错性能不理想和爆腰率高的问题,提出基于模糊决策的谷物烘干机温度自动控制方法.简析谷物烘干工艺,了解烘干设备工作基本流程.将PID控制与模糊控制结合,得到模糊PID控制决策方法.根据烘干工艺分析,将两个输入参量定义为烘干机内部温度在线检测值和内存数据库数据对比下的偏差和偏差变化,将输出定义为最终控制量.根据经验总结获取的控制规则,得到总模糊关系,依据误差与误差变化整体化值,通过模糊推理组建合成规则运算,获取相对应的控制量模糊集合.根据所得结果得到相应模糊规则知识,将规则知识保存至内存数据库.在谷物烘干机温度实时控制过程中,将模糊控制过程转换成查找模糊规则的过程,并根据查找结果输出最终控制量,实现谷物烘干机温度自动控制.实验结果表明,上述方法容错性强,谷物爆腰率低于当前方法,整体性能优越.

This article puts forward a method to automatically control the tem perature of grain dryer based on fuzzy decision. Firstly,we analyzed the grain drying process briefly and understood the basic process of drying equipment. Combined PID control with fuzzy control,we got the fuzzy PID control decision method. By analyzing the drying process,we defined the two input parameters as the deviation and deviation change of internal tem perature on-line detection value of dryer and the data in memory database,and then we defined the output as the final control amount. Based on the control rules obtained by experience,we got the total fuzzy relationship. According to the integration value of error and error change,we used the fuzzy reasoning method to construct the composition rule operation,so as to obtain the corresponding control quantity fuzzy set. According to the resu lts,we could get the corresponding knowledge of fuzzy rule and saved the rule knowledge to the memory database. During the real - time control of tem perature of grain dryer,the fuzzy control process was converted into the process of finding fuzzy ru les,so that we output the final control amount according to the search result. T hus,the temperature of grain dryer could be automatically controlled. Simulation results prove that the method has high fault tolerance. The crackle ratio is lower than that of current method. T hus,its overall performance is better.