线性自抗扰控制的适用性及整定

线性自抗扰控制将被控对象看成串级积分系统,把其他信息都当成不确定性.这种处理方法简单,但是对什么样的系统有效,目前还没有理论给出确定的答案.本文证明任何带有积分行为的严格正则传递函数都可以由线性自抗扰控制的反馈控制器等价实现,从而表明线性自抗扰控制具有广泛的适用性,即只要其他线性控制方法能够控制的系统,线性自抗扰控制同样可以适用.为简化线性自抗扰控制器参数整定,本文针对工业过程中广泛存在的PID控制器,提出将PID参数转化为二阶自抗扰控制参数的方法.该方法转化的线性自抗扰参数以带宽形式表示,从而保留了传统线性自抗扰简单易调的特性,为线性自抗扰控制在工业过程的应用准备了基础.

On applicability and tuning of linear active disturbance rejection control

Linear active disturbance rejection control regards the controlled plant as a cascaded integral system, andtreats other information of the plant as uncertainties. Such a method is simple in design but what kinds of plants the methodcan be applied to control is unknown. In this paper, it is proved that any strictly-proper transfer function with integrator canbe equivalently realized by the feedback controller of a linear active disturbance rejection control (LADRC). This resultshows that LADRC is quite applicable, in that any plant that can be controlled by other linear control methods can becontrolled by LADRC. To simplify the tuning of LADRC, a method to tune the parameters of a second-order LADRC fromthe parameters of an ideal PID controller is proposed in the paper. The parameters are expressed via the bandwidths ofLADRC, thus can be easily re-tuned on-line. This method retains the simplicity of the bandwidth tuning for an LADRC,thus it is ready to apply in industrial processes.