چكيده به لاتين
Abstract:
In the future power systems, the DC micro-grid is undoubtedly the main component of the electrical grids. They can provide the majority of residential, commercial and even industrial loads with higher power quality and reliability. DC microgrids are newer concepts that their protection is a challenging issue. The DC micro-grid with hybrid energy sources is of significant importance for ship and spacecraft applications. In such a system, the coordinated operation of Circuit Breakers (CBs) and disconnecting switches can quickly remove short circuit faults and recover the system very quickly. In this study, an event classification-based protection scheme for multi-bus DC systems, proposed in the reference article is simulated and taken into consideration. The event-based protection scheme transfers less data than conventional data-based protection methods and does not require high-speed communication and synchronization. Every protection unit, using the detection method based on fault current derivative, and employing inductors at both ends of each feeder, is capable of determining the type of event. The decision to isolate the fault zone is based on the unit judgments and the events received from the other related units. To achieve these goals and to confirm the validity of the main reference method, the types of bus and feeder faults is simulated on four-bus DC micro-grid in the Matlab / Simulink environment.
This thesis also presents a method for online fault detection and location in VSC-based DC cable network. The proposed method is based on the inductance estimation of the fault current path. The proposed method can locate the fault with acceptable accuracy even under high impedance faults. This method tested and validated by using simulation data for various faults of pole-to-ground and pole-to-pole.
Keywords: Event-Based Protection, High Level Data communication, Short Circuit Calculations, DC Microgrid, Fault Location, Fault Detection
