Coordinate control of parallel connected power conditioning system for battery energy storage system in Microgrid

This paper concentrates on the control of the integrated battery storage Power Conditioning Systems (PCS) parallel system in Microgrid (MG). The theoretical analysis of the different operation modes are clearly studied, including grid-connected and islanded mode. To improve the power sharing accuracy during the islanded operation, an enhanced droop controller is introduced. The proposed approach is not only able to ensure accurate power sharing but also restore voltage drops due to droop effect and load effect. Moreover, a novel active islanding detection method based on active phase shift with positive feedback (APSPF) is presented in the parallel connected PCSs application. This method can be easily realized and adjust to different grid-connected control strategies. Simulation and experimental results are provided to validate the feasibility of the proposed control approach.