Nonlinear excitation controller design for power systems: an I&I approach

The Immersion and Invariance (I&I) methodology provides a novel approach for nonlinear system control, which is distinct from the traditional feedback linearization and backstepping method. In this paper, a new excitation controller is designed for single machine infinite bus system (SMIBS) based on the I&I approach. Firstly the dynamic model of SMIBS is homeomorphously transformed to a specific form for which a stable lower-order target system is selected. Then the I&I excitation controller is designed by immersing the transformed system into the target system. Simulation results from PSCAD/EMTDC demonstrate that the proposed controller guarantees transient stability of the system after large disturbances.