Limitation of Fault Currents by Positioning ofSuperconducting Fault Current Limiter in ACand DC Microgrid

Abstract

Different types of distributed generation (DG) sources could be connected to the main power grid in order to improve the reliability of the power system, in a smart grid. The association of ac and dc distribution grid are assigned for the efficient connection of renewable power resources. In this function, one of the major difficulties due to these integrations is the excessively large in the fault current due to the activity of DG in the smart grid. A superconducting fault current limiter (SFCL) could be applied, to protect the smart grid from increasing fault current, which has very less power loss and ability to limit initial fault currents effectively. This paper presents validity analysis results of the location of the SFCL and its effects on decreasing fault current in a smart grid having ac and dc microgrid. The entire power system was implemented with a low voltage dc grid connected with a photovoltaic farm and a microgrid having wind farm . Validity analyses were performed for the severe faults with the various SFCL locations. The dynamic location of SFCL in power grid, which could limit fault currents and a positive effect on the DG sources, is found to be the connection point of integration of the each DG sources in the micro grid.