Dual Mode WECS-Based Two-Stage Hierarchical Control of Hybrid Microgrid

Abstract

AbstractThe availability of wind energy as a renewable resource of energy is much higher as it seems, its uses have increased significantly over the years. In this paper, two modes of wind energy conversion system (WECS) are integrated into a microgrid with two-stage hierarchical coordination control, which can perform a decisive transition of grid-connected mode to islanding mode and vice versa. During the transition, the microgrid encountered the problem of stability due to inrush current and efficiency of operation. To overcome it efficiently, the paper proposed a heightened two-stage hierarchical control scheme for dual-mode WECS. The P-V/Q-f droop control method is utilized in the initial stage considering the link-impedance as mostly resistive. The next stage comprised a progressive compensation for the deviation of voltages and currents due to the load variation under grid-connected mode and islanding mode. The control strategy is also tested under different loading conditions while the transition of one mode to another. The dual-stage control scheme also demonstrates the parameters to accomplish real and reactive power bifurcation with AC main grid, two types of WECS, and different loads. To verify the proposed control structure, the MATLAB/Simulink atmosphere is used.KeywordsHybrid microgridHierarchical controlWind energy conversion systemBidirectional converterDual operating mode