Investigation of a micro-grid operation: A case study of Heron Island network, Australia

The increased implementation of renewable energy sources, especially in island micro-grids, can have a significant effect on the quality of the power within that network. Heron Island, located off the coast of Queensland, Australia, has historically been powered by diesel generators. Recently however, Photovoltaic (PV) arrays have been added to the island to reduce the reliance on fossil fuel. This PV addition to Heron Island has brought some power quality issues due to a combination of features which are unique to the Heron Island micro-grid. These features include: small inertia diesel generators, high R/X ratio cables, a complete lack of coordination of equipment and high PV penetration. Issues relating to power quality, such as over/under-voltage, because of a combination of these factors have been reported on the island. This paper investigates the effect of distributed generators on power quality and stability on an island micro-grid with these unique factors.