Designing Automatic-Reset Controllers With Higher-Order Derivatives

The article presents examples evaluated as part of the a software package development for verification and evaluation of controllers with automatic-reset (AR) and higher-order derivatives. AR represents a positive controller feedback for eliminating steady-state control error due to acting disturbances, which is based on the evaluation of steady-state controller output and already during the century forms the basis of industrial controllers. Even though the AR control structure with proportional and proportional-derivative controllers are usually referred to as series proportional-integral (PI) and proportional-integral-derivative (PID) controllers, they do not contain an explicit integrator. This feature is essential from the point of view of behavior when limiting the output of the controller. The developed software package is intended to be used to verify properties of the mentioned controllers, such as the sensitivity to process model uncertainties, the effect of measurement noise, and the responses under constrained control signals. It will also provide a comparison with common types of PID controllers.