From PID Technique to Active Disturbances Rejection Control Technique

In this paper, advantages and disadvantages of classical PID are investigated from its basic principles. A new type controller Active Disturbances Rejection Controller(ADRC) with excellent characters is constructed via some links with especial functions,such as Tracking Differentiator(TD),Extended States Observer(ESO)and Nonlinear PID(NPID),which are based on the nonlinear control mechanisms. Furthermore, the new active disturbances rejection control technique is formed. The new controller possesses the following characteristics:the algorithm is simple; the adjustment of the parameters is easier.