The making and breaking of electric circuits with switch gears may result in abnormal over voltages in power systems having large inductance and capacitance. The over voltages may go high as six times the normal power frequency voltage. In circuit breaking operation, switching surges with a high rate of rise of voltage may cause repeated re striking of arc between the contacts of a circuit breaker, thereby causing destruction of circuit breaker contacts. The switching surges may include high natural frequencies of the system.
0 comments:
Post a Comment