A multiple model-based controller for nonlinearly-parametrized plants

The paper describes a multiple model-based controller design for a class of nonlinearly parametrized plants. The main idea is to combine a global robust controller with local nonlinear controllers within the framework of multiple models and switching to achieve and maintain acceptable performance of the overall system. In particular, the role of the robust controller is to bring the state of the system to a region where local nonlinear models are valid, and then to employ a switching strategy in this region to reduce the output error to zero. The suggested scheme combines a new indirect variable structure controller (IVSC) with fixed and adaptive nonlinear controllers for nonlinearly-parametrized plants. It is also shown that the new IVSC, combined with the suggested controller design for nonlinearly-parametrized plants, enables a relatively straightforward stability analysis of the overall system.