模糊PID控制算法在恒速升温系统中的应用

Application of fuzzy-PID control algorithm in uniform velocity temperature control system of resistance furnace

匀速升温控制是个复杂的过程,具有大惯性、纯滞后、非线性等特点,难以得到精确的数学模型。考虑到这些特点,为提高控制精度,将Fuzzy-PID算法应用于电阻炉温度控制系统,当误差较大时采用模糊控制,误差较小时采用模糊PID控制,实现了2种控制方法的优势互补,在此基础上,给出了Fuzzy-PID控制器设计、硬件结构和软件设计,实验曲线表明该控制算法可以获得满意的控制效果,采用模糊PID控制的效果明显优于常规PID控制。

The process of uniform velocity temperature control is a complicated process and has the characteristics of big inertia, pure time-delay and nonlinearity, and it is hard to obtain the exact mathematic model. Considering these characteristics, to improve the control performance, a Fuzzy-PID controller is proposed. The fuzzy control is used when the error is large, and the PID is used when the error is small, which takes the advantages of these two methods complementarily. Based on this, the designs of Fuzzy-PID controller and hardware circuit and the software structure are presented. Experiment curves prove that the proposed control algorithm can obtain satisfactory control effects, and the effect of Fuzzy-PID control is obviously better than that of conventional PID control.