Design of PD control based on GPC in a multirate system

This paper proposes a design method for PD control in a multirate sampled-data system, where the sampling interval of plant output is an integer multiple of the hold interval of control input. The proposed PD control system is based on a multirate generalized predictive control (GPC) law. Because this law can be redesigned independently of the sample response, intersample ripples are eliminated without changing the sampled output response. Hence, in the proposed method, integral compensation is not included, but the ripples between sampled plant outputs can be eliminated. Simulation results show the effectiveness of the proposed method.