An Offset-free Model Predictive Controller for DC/DC Boost Converter Feeding Constant Power Loads in DC Microgrids

The wide utilization of power electronic converters causes the constant power load stability issue in DC microgrids. This paper proposes an offset-free model predictive controller for a DC/DC boost converter feeding constant power loads. First, a baseline nonlinear model predictive controller is designed by solving a receding horizon optimization problem explicitly. Then a higher-order sliding mode observer is utilized to estimate the unknown load variation and system uncertainties. Finally an offset-free controller is integrated by the baseline controller and observer. The proposed controller achieves optimized transient dynamics and accurate tracking with large signal stability. Simulation results are presented to verify the proposed approach.