Abstract
Many design problems of process control systems have the the following two characteristic features: (1) To obtain a complete model of the process is extremely diffcult, (2) the specification for the closed-loop dynamic performance is puite moderate. The analog PID controller is regarded as the most suitable device for such a situation, because its simplicity in the configuration and the ease of implementation tolerate and/or balance the model uncertainty. In digital control systems, however, we have greater flexibility in the controller configuration beyond the PID actions, still keeping the simplicity and the ease of implementation.
In this paper, we propose an integrated design procedure of digital control systems including modelling, with the purpose of exploiting the flexibility of digital controller to incorporate the model uncertainty in a proper way. The procedure is essentially based on the partial model matching which offers a reasonable way to simplify the design and the controller configuration under model uncertainty. Given a “one-shot” stop response data of the plant contaminated by the noise, the procedure determines a controller in a simple form which is a natural extension of digital PID controller. The design methodology is applied to a digital control of a simple system.
