PID参数整定新方法在锅炉蒸汽压力系统中的应用

A new method for PID parameters tuning and its application in boiler steam pressure system

传统的Ziegler-Nichols参数整定方法已经在PID控制设计中得到了普遍应用,然而由于未对超调量进行具体限制而表现出一定的局限性.本文根据系统阶跃响应曲线的几何特性,通过求曲线包络的面积获得在被控对象的阶跃响应超调量严格限制情况下的PID控制器的3个参数值.该整定方法具有同时保证系统超调量小和响应速度快的双重优点,一定程度上弥补了传统PID参数整定方法的不足.把这种新的整定方法应用到锅炉蒸汽压力控制系统设计中,在Simulink环境下仿真表明,相比于经典Ziegler-Nichols方法,该整定方法具有更好的控制效果.

Aimed at the limitation of conventional Ziegler-Nichols parameter tuning method widely used in PID controller design,based on the geometric characteristics of system step-response curve,this paper gets three parameters of PID controller changing with circumstances under the condition that overshoot is strictly limited by calculating the area enveloped by the step response curve.The new tuning method can keep the little overshoot for the system and ensure a fast response speed,which makes up for the deficiencies of traditional PID parameter tuning method to some extent.This tuning method is applied to the boiler steam pressure control system design,and the simulation results shows that the new tuning method has a better transient performance compared with the classical Ziegler-Nichols method.