ABSTRACT
Transient recovery voltage (TRV) refers to the voltage appearing across circuit breaker contacts after it interrupts current. This chapter introduces TRV calculations and mitigation, at a level sufficient for educational purposes. In applications, the TRV is usually calculated based on the electrical system model only, ignoring interactions between the arc and system models. If the TRV failure occurs during a normal opening, it probably leads to a short circuit in the failed breaker, which also leads to backup clearing and possible cascading effects. TRV analysis is important because it affects protection of the power system. TRV phenomena may consist of high-frequency transients in lumped-parameter circuits, along with traveling wave transients in distributed-parameter overhead lines and cables. The most severe TRV comes from a three-phase ungrounded fault, but those faults are quite rare. The standard TRV application for an effectively grounded system is based on a three-phase grounded fault at the breaker terminals.
