Calculation of loadability in a droop controlled DC microgrid with constant power loads

In this paper, the maximum real power load in a dc microgrid bus is traced geometrically. The dc microgrid is droop-controlled with the loads being constant power loads. The generalized circle diagram approach used in a conventional power system is modified to be used in a droop-controlled dc microgrid for this purpose. The different types of buses present in a dc microgrid are described and the locus of operating points is then obtained by applying the generalized circle diagram approach. The proposed method is verified by simulations on a 4 bus dc microgrid.