本文提出一種以低階模式為主來設計一個改良式PID控制器的方法。與Haggland及Astrom所提者作相對照,本文的方法純粹以模式的逆轉方式演導而得。在逆轉演導過程中,引導了一個領先元素進入基本環路中,而形成了一個MSP(即:改良式Smith Predicto)對等系統。因為如此,此改良式PID控制器兼具設定點追隨及負荷排除的兩項功能。所有控制器中的參數都直接由上述的MSP系統演導而得。同時,針對傳統式的PID控鄅器,本文亦由改良式PID控制器加以適當的簡化並提供其調諧公式。
A modified PID (m-PID) controller design using low order dynamic models is presented. In contrast to the one of Haggland and Astrom (1985), the controller uses model-based parameters. Synthesis of such a controller is by way of an inverse-based approach. By this approach, a pure lead is introduced into a l=p to make the system equivalent to a modified Smith predictor (MSP) control system. Tuning rules for this m-PID controller are then derived from this equivalent system. For robustness, gain and phase margins are analyzed. It is found that this proposed m-PID control system has good responses to both set-point and load changes. Tuning rules derived from reduction of this m-PID controller for conventional PID control have also been presented.