Energy management and coordinated control method for multi-source/multi-load DC microgrid

Abstract

The energy management and coordinated control of low voltage DC (LVDC) microgrid is one of most important issues for ensuring the system reliable operation. The traditional control methods based on the DC bus voltage signal (DBS) would give rise to DC voltage deviation under different operation conditions, which have an adverse impact on constant power load (CPL) within LVDC microgrid, and then lead to system instability. An energy management and coordinated control method based on local information was proposed. The energy management modes, switching conditions and coordinated control method were analyzed in detail under grid-connected operation, converter current-limit and islanding operation conditions. An open-loop pitch angle control method with constant voltage control could eliminate DC-link voltage fluctuation, enhance power quality and system stability under islanding operation conditions. Finally, the effectiveness of proposed method was verified by simulation results.