A busbar differential protection based on fuzzy reasoning system and Rogowski-coil current sensor for microgrid

Abstract

Busbar protection grids are always important, but high-speed regimes are now needed more than ever because many power systems operating in microgrid should achieve safe and stabile operation. For this purpose, protection concepts that require time coordination such as overcurrent relays and distance protection are no longer acceptable. Digital differential protection uses innovative algorithms to comply with the protection requirements busbar with fast times switching for all faults. The proposed scheme provides protection for any fault in the Busbar of the microgrid and isolates the smallest part possible, to allow the rest of the system to continue operating. The main difficulty in busbar protection using current transformer (CT) may appear during saturation. Therefore, with the use of the Rogowski coil current sensors (RC) can overcome the saturation in CT; in addition, it has many unique features. The protection system consists of a unique combination using differential protection using RC and an intelligent tool to achieve reliable busbar protection with a minimum of delay for evolving faults. Performance has been verified for a variety of operating conditions. The results have confirmed the superior performance of the protection solution. In general, Rogowski coils have performance characteristics that are favorable compared to conventional CTs.