Decoupling internal model control for multi-variable non-square system with time delays
A new decoupling internal model control(IMC)method was proposed for the multi-variable non-square systems with multiple time delays by introducing the conception of generalized inverse.The traditional IMC based on the inverses of nonsingular matrices was confined to square systems,so the generalized inverse was imported to design the internal model controllers by calculation in frequency domain.Time delays were approximated by the Taylor expansion diagrams.To guarantee the stability and regularity of system,special filters were designed to counteract unstable poles brought forth by the Taylor approximation.The results showed that when the model did not mis-match badly,the output curves had less than 20% overshoot and almost zero deviation from steady state.The output also had good performance about dynamic decoupling,and multiple time delays control.But the control system was sensitive to the change of time delays.Based on IMC system,the response would be better if the model matched more satisfactorily.