Genetic Approach to Design Decentralized PID Controllers for Multi-variable Processes

摘要

Design of PI/PID controllers for multi-input-multi-output (MIMO) systems are always difficult due to interactions and decoupling in the systems. In this paper, a simple and effective design methodology of decentralized PID controllers is presented. Initially the system is decoupled using decoupler matrix and the first-order-plus-delay-time (FOPDT) model of each subsystems is obtained. The Pade approximation replaces the delay time terms in the FOPDT subsystems. A genetic approach is applied to obtain the parameters of the decentralized PID controller. The proposed method is compared with existing method and found suitable for most of the applications. The two simulation examples are included to demonstrate the effectiveness of the proposed method.