Modern multi-MW wind generators have used multi-level converter structures as well as\nparallel configuration of a back to back three-level neutral point clamped (3L-NPC) converters to\nreduce the voltage and current stress on the semiconductor devices. These configurations of converters\nfor offshore wind energy conversion applications results in high cost, low power density, and complex\ncontrol circuitry. Moreover, a large number of power devices being used by former topologies results\nin an expensive and inefficient system. In this paper, a novel bi-directional three-phase hybrid\nconverter that is based on a parallel combination of 3L-NPC and â??nâ?? number of Vienna rectifiers have\nbeen proposed for multi-MW offshore wind generator applications. In this novel configuration, total\npower equally distributes by sharing of total reference current in each parallel-connected generator\nside power converter, which ensures the lower current stress on the semiconductor devices. Newly\nproposed topology has less number of power devices compared to the conventional configuration of\nparallel 3L-NPC converters, which results in cost-effective, compact in size, simple control circuitry,\nand good performance of the system. Three-phase electric grid is considered as a generator source for\nimplementation of a proposed converter. The control scheme for a directly connected three-phase\nsource with a novel configuration of a hybrid converter has been applied to ratify the equal power\ndistribution in each parallel-connected module with good power factor and low current distortion.\nA parallel combination of a 3L-NPC and 3L-Vienna rectifier with a three-phase electric grid source\nhas been simulated while using MATLAB and then implemented it on hardware. The simulation and\nexperimental results ratify the performance and effectiveness of the proposed system.
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