Hybrid AC/DC microgrids: A generalized approach for autonomous droop-based primary control in islanded operations

This manuscript establishes a comprehensive approach to improve the primary voltage and frequency controls in hybrid AC/DC microgrids (MGs). Dealing with the islanded operations, the proposed approach ends in an efficient autonomous power sharing task through the interlinking converter (IC). An improved droop-based power control is proposed and then applied to the IC between the AC and DC MGs. As a salient contribution, a generalized mathematical basis is established to determine the active power transfer through the IC. The founded approach portrays two prominent features namely (1): it can be readily deployed for general lines' impedances which are interconnecting the source and loads in AC MG, and (2): the required control commands are explicitly generated only by voltage and frequency measurements at IC terminals. Moreover, to improve performance of the AC MG, the proposed approach is extended to control the reactive power contribution by IC. To obtain a general insight regarding the affecting parameters on the proposed approach, proper sensitivity studies are conducted. A typical test system is numerically analyzed to explore efficiency of the proposed approach. Results are discussed in depth.