SELECTION OF FAULT CURRENT FOR A CIRCUIT BREAKER FROM THE LAYOUT OF A TYPICAL SUBSTATION

Abstract

High-voltage transmission and distribution networks are the backbone of modern power generation and distribution systems. Any type of fault can be very destructive to power system. A great deal of study, development of devices, and design of protection schemes have resulted in continual improvement in the prevention of damage to transmission lines and equipment and interruptions in generation following the occurrence of a fault. The continuity and quality of electricity delivered safely and economically by todays and future’s electrical power networks are important for both developed and developing economies. The correct modeling of power system equipment and correct fault analysis of electrical networks are pre-requisite for ensuring safety and they play a critical role in the identification of economic network investments.

Faults on the transmission and distribution system can lead to severe economic losses. Rapid information about the type and the location of the fault can assist the task of repair and maintenance, thereby minimizing the economic effects of power interruption. Usually, faults are considered dangerous because of over current that they create. Circuit breaker is a very unique device which is being used widely for the interruption due to occurrence of a fault in the power system. For the proper selection of circuit breaker it is necessary to find out the maximum fault current that can occur due to a fault in the system.