Future Reference Trajectory Improvement in Self-tuning I-pd Controller Based on Generalized Predictive Control Law

In this paper a new design method of a self-tuning I-PD controller is proposed. The I-PD controller is designed based on a generalized predictive control (GPC) law. By using a conventional design method of the I-PD controller based on the GPC law, it is impossible to introduce future reference trajectory into the I-PD controller. The future reference trajectory of the GPC approaches a setpoint value gradually from a present output, that is one of the features of the GPC. The proposed method can introduce the advantage of the GPC into the IPD controller exactly because the proposed method expresses the future reference trajectory suitably when the set-point value is given as a step type signal. This paper shows that the structure of a PID controller based on the GPC law becomes an I-PD type by using the proposed method and that a design parameter of the GPC which adjusts the future reference trajectory influences only an integral time of the I-PD controller. In order to illustrate the effectiveness of the newly proposed method, numerical examples are shown. Copyright c ©2005 IFAC