Distributed Power Generation: A micro-grid control system including an automatic "Virtual Islanding" mode which enables a smooth transition from a grid-connected to an islanded state

Andrew J. Roscoe (Inventor), Richard C. Knight (Inventor), David R. Trainer (Inventor)

Research output: Patent


Distributed power generation systems generally comprise a number of power sources and electrical power loads interconnected by a distribution network. Electrical switches and fuses are provided such that local groups of power sources and power loads can be established. Should there be a degradation in the distribution network in terms of a set of criteria such as electrical frequency, current or voltage then the switch or fuse may be thrown to establish each local group as an island. By monitoring divergence from a set of criteria a method and controller may be utilised whereby the distribution network as a whole is considered and configured to establish virtual islands which operate prior to the establishment whether inadvertently or deliberately of actual islands within the distribution network.; In such circumstances the transition from normal operation for the distribution network to islanded operation for the distribution network is less severe.
Original languageEnglish
Patent numberUS9118196 B2
Priority date14/05/09
Publication statusPublished - 25 Aug 2015



  • distributed power generation
  • power generating systems
  • electrical power loads
  • distribution networks
  • electrical power sources

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