Global Robust Output Regulation of a Class of MIMO Time-Varying Nonlinear Systems and Its Application to PMSM

This article investigates the global robust output regulation of a class of multi-input multi-output (MIMO) time-varying (TV) nonlinear systems with a TV exosystem. Existing linear or nonlinear internal model designs are inadequate for the output regulation problem in TV situations. Therefore, we first transform this control problem into a global robust stabilization problem (GRSP) for a more complex MIMO TV augmented nonlinear system by constructing a TV internal model. Under a series of standard assumptions, this system can be globally stabilized by a recursive state feedback controller. Finally, the proposed algorithm is applied to the disturbance rejection problem of a permanent magnet synchronous motor (PMSM) position servo system, and the experimental results demonstrate its effectiveness.