改进的加热过程模糊自调整PID算法及仿真分析

Improved Algorithm and Simulation Analysis for Fuzzy Adaptive PID of Heating Process

为解决工业控制中大惯性、纯滞后、参数时变的非线性受控对象难于控制的问题,提出一种改进的控制算法。该算法采用1个单输入3输出的模糊控制器结构代替3个单输入单输出模糊控制器结构,通过Mam-dani模糊推理运算自调整PID(Proportional Integral Derivative)参数,并结合Smith预估补偿控制作用,优化系统动态响应指标,改善了控制器性能。将其应用于注塑机加热过程的温度控制中,并与常规PID控制器和Smith预估PID控制器比较。仿真结果表明,该控制器各项性能均好于其他两种控制器,调节时间为420 s,超调量和稳态误差均为0,具有抗干扰性强和鲁棒性好等优点,为进一步改善注塑机加热过程的实际控制性能提供了理论依据。

In order to solve the problem of control difficulty for the nonlinear controlled object, which has the characteristics of larger inertia, the pure time delay and the time-varying parameter in the industry eontrol, an improving control algorithm was proposed. Three SISO （Single-Input/Single-Output） fuzzy control was replaced by a single input-three outputs fuzzy control, and the PID （Proportional Integral Derivative） controller parameters were adjusted by the fuzzy inference arithmetic based on Mamdani. The qualities of the system＇s dynamic response were optimized and the controller characteristics were improved with Smith estimating compensation. The controller was applied on temperature control of heating process of a pouring plastics machine, and compared with the traditional PID controller and the Smith estimating PID controller. The simulation result shows that the qualities of the controller are obviously better than the other two controllers. The controller has the characteristics of regulation time of 420 s, overshoot and steady-state deviation of 0, strong resistant ability to interference and good robustness. A theory basis is provided to improve the control characteristics of heating process of the pouring plastics maehine. It has certain reference value to control other similar industry objeets.