Design of PIDA Controllers for High-order Integral Processes

In this paper we propose a methodology for the design of Proportional-Integral-Derivative-Acceleration (PIDA) controllers for integral processes. In particular, starting from a high-order process model, which can be obtained by means of a relay-feedback experiment, the controller parameters are determined by applying a general Internal Model Control Strategy and reducing the controller transfer function to the PIDA form by approximating it with a Maclaurin truncated series. An additional low-pass filter is added to compensate for the measurement noise effect. Both cases with the presence and absence of the integral action in the controller are analyzed. Illustrative examples are given to demonstrate the effectiveness of the methodology and its suitability to be applied in a practical context.