These studies are done to determine the magnitude of the current flowing throughout the power system at various time intervals after a fault occurs. Consequently the protective system is called on to detect, interrupt and isolate these faults. The duty imposed on the system equipment depends the magnitude of the fault current, which is dependent on the time from the fault inception.
Our calculations can be based on the most important international standards, such as: IEC EN 60909-0 (2001), IEEE C37-10, IEEE C37-13, IEC 61363-1. Otherwise calculations can be based on the universally accepted superposition method.
Calculation results are used to select fuses, breakers, switchgear ratings and to set the protective relays.