'\B:,TRAC r· Recently there has been a resurgence of conccrn about islanding of grid-connected photovoltaic (PY) ,ystems rhis condition occurs when the PY system continues to energize a section of the grid after that section has been Isollted from thc main utility voltage source. Generally, islanding is undesirable for a number of reasons, and it is therefore important that PY systems incorpora...

electronic copies of this thesis document in whole and in part in any medium now known or hereafter created. ABSTRACT Over the last decade, penetration of microgrids containing distributed generation (DG) sources has increased in grid distribution systems. This requires the stable operation of microgrids when connected to the distribution system as well as during islanding. Islanding that is fa...

Islanding is the situation in which part of the power grid, consisting of load and distributed generation (DG) is isolated from the utility grid remaining active, i.e. serving load. The idea of islanding parts of the distribution network in case of faults, in order to increase the consumer quality of service, is the basic notion behind the formation of Microgrids. In the context of Microgrids, ...

This paper proposes active frequency drift (AFD) as an anti-islanding method applied to micro-inverters with uncontrollable reactive power. When using ordinary inverter topologies, such as full bridge inverters in photovoltaic systems, the islanding phenomenon can be detected with reactive power-based methods, such as reactive power variation. However, when the inverter topology cannot control ...

Distributed generation is a form of electric power privatization. Consumers install their own power station to supply the local loads and/or share in the utility loads. Many protective problems have been developed due to the existence of these distributed generations. However, a protective strategy should be developed to protect the system and the generator itself from different hazards. One pr...

Controlled islanding has been widely discussed in the literature as a novel concept for the power system protection. However, the islanding can result in unbalanced islands where the power mismatch will often cause an instability that can lead either to a subsequent load shedding or generator tripping within the islands. Controlled VSC-HVDC links can mitigate the negative consequences of the co...