Title :
Overvoltages due to switching off an unloaded transformer with a vacuum circuit breaker
Author :
Popov, Marjan ; Acha, Enrique
Author_Institution :
Univ. St. Cyril & Methodious, Skopje, Macedonia
fDate :
10/1/1999 12:00:00 AM
Abstract :
When a vacuum breaker is used to disconnect an unloaded transformer, high overvoltages may result on the secondary side. The phenomena of current chopping and multiple reignitions after contact opening, shortly before current zero, play a significant role in generating these overvoltages, Furthermore, the transient recovery voltage (TRV) is also influenced by virtual current chopping which may lead to fast interruptions and reignitions. The paper reports on a vacuum breaker model implemented in the ATP-EMTP program. Simulations have been performed to determine overvoltages generated by the vacuum breaker, before and after suppression. Network elements were simulated by simplified models of limited complexity
Keywords :
overvoltage protection; power system analysis computing; power system protection; power transformers; switching; vacuum circuit breakers; ATP-EMTP; computer simulation; current chopping; disconnection; interruptions; multiple reignitions; secondary side overvoltages; transient recovery voltage; unloaded transformer switching; vacuum circuit breaker; Capacitance; Circuit breakers; Circuit simulation; Furnaces; Large Hadron Collider; Surges; Switchgear; Switching circuits; Vacuum arcs; Voltage;
Journal_Title :
Power Delivery, IEEE Transactions on
