Grid side inverter control scheme for robust fault ride through with enhanced overload capabilities

In this paper a predictive control scheme for current injection into three phase grids with power converters is presented. The proposed control scheme shows an excellent current quality even under adverse grid conditions like unsymmetrical grid faults. By usage of iron powder inductors as filter elements for the grid current a very high overload capability of the inverter can be achieved without oversizing these filter elements. The performance of the proposed control is experimentally verified with a two-level three-phase active front end.