Application of the Multi-Input Multi-Output One-Step-Ahead Adaptive Controller to a Power Plant Boiler

The Multi-Input Multi-Output One-Step-Ahead (MIMO O.S.A.) Adaptive Controller [1,2] is applied to a power plant boiler to control three outputs using three input variables. The power plant boiler is the same system to which a multivariable self-tuning controller was previously applied in [3]. This paper shows the improved performance of the MIMO O.S.A. adaptive controller over that of the multivariable self-tuning controller shown in [3]. The reason for this improvement is that a sampling period smaller than the largest time delay in the system is not allowed in the design of multivariable self-tuning controller. The MIMO O.S.A. adaptive controller does not impose this constraint on the sampling period. This paper also shows that using the multi-input multi-output weighted one-step-ahead (MIMO W.O.S.A.) adaptive controller reduces the magnitude of fluctuations of the control signals which result in improved control of the boiler outputs. Comparison of the performance of the MIMO W.O.S.A. adaptive controller with the performance of the existing PI controllers, when the system goes through a transient mode, shows that the outputs stay closer to their set points when they are controlled by the adaptive controller.