Nonlinear model predictive control of HVDC for inter-area oscillation damping

This paper presents a nonlinear model predictive control (NMPC) strategy for high-voltage direct current (HVDC) transmission to damp inter-area oscillations in the power grid. An ensemble Kalman filter (EnKF) method is implemented to generate nonlinear model-based future predictions within a finite horizon. Unlike existing control methods that are based on approximate linearization of a system, the NMPC-EnKF approach maintains full nonlinearity in the AC-HVDC system by introducing ensembles to represent and propagate the distribution of states and errors. The proposed approach is tested on both a modified two-area, four-machine system and a modified IEEE New England system. Both small- and large-signal-disturbance stability studies are tested to validate the performance of the proposed approach. Extensive results show the effectiveness of the NMPC-EnKF approach for damping inter-area oscillations.