4T - Introduction to Short Circuit Current Calculations

Description:

This course presents the subject of short-circuit studies in a very structured fashion. First, a simple equivalent circuit is developed for a generic power system; system impedances are recalculated to joint base and fault are calculated at various locations throughout the system. A detailed explanation is offered for the calculation of three-phase faults. Any commercial power system software package can also verify explained techniques.

The Short-circuit studies determine the magnitude of the prospective currents flowing throughout the power system at various time intervals after a fault occurs. The magnitude of the currents flowing through the power system after a failure varies with time until they reach a steady-state condition. The information is used to select fuses, breakers, and switchgear ratings in addition to setting protective relays.

This behavior is due to system characteristics and dynamics. During this time, the protective system is called on to detect, interrupt, and isolate these faults. The duty imposed on this equipment depends on the magnitude of the current, which depends on the time from fault inception. This is done for various types of faults (three-phase, phase-to-phase, double-phase-to-ground, and phase-to-ground) at different locations throughout the system. In the Introduction to Short Circuit Current Calculations, you'll learn:

• Short circuit current calculation for the industrial power system
• Basic theory for short circuit calculation in the electrical power system
• How excessive short circuit currents can be mitigated

Contact Hours: 4 Hours - Technical

Instructor: Velimir Lackovic