The Good Gain method for simple experimental tuning of PI controllers

A novel experimental method -- here denoted the Good Gain method -- fortuning PI controllers is proposed. The method can be regarded as analternative to the famous Ziegler-Nichols' Ultimate Gain method. The approach takenresembles the Ziegler-Nichols' method as it is based on experiments with theclosed loop system with proportional control. However, the method does notrequire severe process upset during the tuning like sustained oscillations.Only well-damped responses are assumed. Furthermore, in the present study itis demonstrated that the approach typically gives better stability robustnesscomparing with the Ziegler-Nichols' method. The method is relatively simpleto use which is beneficial for the user. A theoretical rationale based on second order dynamics is given.