Island detection methods and grid current control methods in SPV-based energy systems

Abstract

ABSTRACT Nowadays, greater penetration of distributed power generation sources (DPGSs), which includes both conventional and renewable energy sources, is taking place, with clear evolution of active grids, i.e. with energy storage systems, there is a possibility to work in an island mode and can be linked to a flexible transmission system, but due to this complexity, the requirements depend on the size and the level of integration. Monitoring of grid is a crucial part, and detection of possible islanding is very important, and in the case of low-power DPGSs like photovoltaic (PV) sources, it is termed as anti-islanding requirement and islanding detection is required in such cases. In future, smart micro grid (SMG) is the scenario i.e. capable of switching automatically to stand-alone operation during grid faults and reconnecting to the grid immediately after the fault is cleared. For this to happen, detection of islanding is important since it is not possible to predict the level of connection and information exchange reliability. Islanding detection is attained with attention towards amplitude and frequency variation of the grid voltages, and the performance of islanding detection relies on reliability, selectivity and minimum perturbation with reference to effects on grid voltage amplitude, and the frequency of the non-detection zone (NDZ) is defined.