Multiple models direct adaptive feedforward decoupling controller for a nonminimum phase system

For a nonminimum phase system, when the parameters of the system change abruptly, a multivariable direct adaptive feedforward decoupling controller using multiple models is presented to improve the transient response. In this paper, the controller consists of multiple fixed controllers and two adaptive controllers. The fixed controllers are derived from the corresponding fixed system parameter models directly and used to cover the controller parameter set with their neighborhoods. By the choice of the weighting polynomial matrix, it not only eliminates the steady state error, but also decouples the system. The global convergence is given and several simulation examples illustrate the power of the derived multiple models adaptive decoupling controller.