A reactive power control strategy of the grid-connected inverter for microgrid application

The objective of this paper is to propose a reactive power control strategy of the grid-connected inverter for microgrid application. The proposed strategy can actively participate to regulate the voltage, realize the islanding detection, reduce the power quality impact of islanding detection and simplify the controller design. When the distributed energy resource (DR) of the microgrid system generates power to the grid, it may cause the voltage of the point of common couple (PCC) rising. The proposed strategy is to use the grid-connected inverter with the reactive current control to regulate the PCC voltage. Meanwhile, the reactive current disturbance is used to detect the variable frequency in islanding condition. Also, the experimental results are shown to confirm the validity of the design concept of the proposed strategy.