PROJECT TITLE :

Power Management for a Hybrid AC/DC Micro grid with Multiple Sub grids - 2017

ABSTRACT:

This paper proposes a brand new topology of a hybrid ac/dc microgrid, where there are multiple subgrids connected to the common bus by bidirectional ac/dc converters (BADCs) and bidirectional dc/dc converters (BDDCs) in the system. The rated ac frequencies in different ac subgrids and the rated dc voltages in numerous dc subgrids will be totally different for various applications. All the storages within the system are focused to create a storage subgrid for convenient management and high efficiency, that maintains the common bus voltage. To ensure the hybrid microgrid operates well, a proper power management method is important to manage the facility flow among multiple subgrids. This paper proposes a decentralized power management method for the hybrid microgrid to make the interacted subgrids operate in coordination and support each other. First, taking the characteristics of the common bus configuration into thought, a Pdc - vdc2 droop management strategy is proposed to keep up the common bus voltage and to realize power sharing among storages within the storage subgrid. Second, as the interaction among multiple subgrids is additional sophisticated compared to the standard hybrid, a coordinated power management strategy based mostly on the common bus voltage, ac subgrid frequency, and dc subgrid voltage is intended for the BADCs and BDDCs to appreciate the ability interaction among different subgrids. Furthermore, the proposed strategy takes the capacities and load types of each subgrid into thought; hence, it's still appropriate when the capacities of subgrids are mismatched and it can guarantee the facility quality of the subgrids with high proportion of essential hundreds. The effectiveness of the proposed power management methodology is verified by the $64000-time hardware-in-loop tests.