A New Model Predictive Current Controller for Grid-Connected Converters in Unbalanced Grids

Distributed energy resources are often connected to low-voltage distribution networks where the grid voltages may be unbalanced. This leads an unwanted ripple in output active power at twice fundamental frequency. In this article, a new model predictive current controller is proposed for unbalanced grids. The variable switching frequency of existing controllers fixed and quality improved. A Kalman filter estimator used extract positive negative sequence components. calculation time compensation technique proposed, which offers superior accuracy approaches. voltage discretization strategy outlined, its effectiveness demonstrated. Finally, system stability verified theoretically. Simulation laboratory results included prove robustness support theoretical analysis.