Safety and reliability for Smart-, Micro- and islanded grids

Up to now the focus of Micro- and Smart-Grids analysis was to maintain the load flow using massive information technology to increase the supply guarantee by independent islanded-grids in regulator operation conditions but neglecting fault operation. In the paper will be shown the importance of a high short circuit power and low zero sequence impedance, listing of axioms for network planning and a listing of measures for islanded network operation.