Centralized Controller Design Based on Singular Value Decomposition

A novel decoupling control method based on singular value decomposition is proposed for a strongly coupled multivariable system with different time delays in process control. A centralized PI (proportional-integral) controller is derived via internal model control (IMC), and its robust stability is analyzed systematically. The proposed method is able to eliminate the interaction, and can be applied to both the square system and the non-square system, obtaining a general design for a multivariable system. Simulation research indicates the effectiveness of this method, with its strong decoupling ability and robust stability. Moreover, errors caused by model reduction approximation and system parameter perturbation are eliminated as they became apparent. The design is simple and can be easily implemented.