Stability of synchronized motions of inverter-based microgrids under droop control

We consider the problems of frequency stability, voltage stability and power sharing in droop–controlled inverter–based microgrids with meshed topologies and dominantly inductive power lines. Assuming that the conductances in the microgrid can be neglected, a port–Hamiltonian description of a droop–controlled microgrid is derived. The model is used to establish sufficient conditions for local stability. Furthermore, we propose a condition for the controller parameters such that a desired steady–state active power distribution is achieved. The robustness of the stability condition with respect to the presence of conductances is analyzed via a simulation example based on the CIGRE benchmark medium voltage distribution network.