Evaluation of the Performance of Droop Control Scheme for Interlinking Converter in Stand-Alone Hybrid Microgrid

Abstract

In an AC-DC hybrid microgrid, the AC and DC sub-grids accommodate both the sources and the loads which can be either AC or DC by nature. Interfacing of these AC and DC sub-grids are done by interlinking power converters. The converter can operate in rectifier and inverter or stop mode, according to the situation condition demands. Interlinking power converter which links the AC and DC sub-grids in the hybrid microgrid plays a vital role for achieving the stability of whole microgrid. A bidirectional droop control method for the converter is proposed, which measures the power demand of AC sub-grid and DC sub-grid in accordance with terminal AC bus frequency and terminal DC bus voltage, respectively. It also determines the direction and the magnitude of the power transfer through converter. The control of power being transferred between AC and DC sub-grids can be achieved easily using the proposed strategy. The effectiveness of control strategy is verified by time-domain simulation in MATLAB/Simulink