A distributed minimum losses optimal power flow for islanded microgrids

In this work, the minimum losses optimal power dispatch problem for islanded microgrids with distributed energy resources (DER) is solved by means of a distributed heuristic approach. Optimal power management is performed almost in real time, with a predefined schedule, i.e. every 5 min, and the solution is applied to generators when the current operating solution violates voltage or current constraints or when the current configuration produces too large power losses. The operating point of both inverter-interfaced generation units as well as rotating production systems can be modified simply using local information. The latter are voltage measurements and power injections or loads data of local and nearby nodes, therefore information processed at each bus derive from communications between adjacent nodes. The distributed algorithm is iterative but also fast and easy to understand, since it is based on the use of power flow equations. It can be employed for small and medium size networks showing tens of nodes and test results prove that convergence happens in few iterations.