Expression of Rate of Rise of Recovery Voltage across a Circuit Breaker with Fault Current Limiter in Bus-Tie Location

The present paper examines the mathematical expression of the rate of rise of recovery voltage (rrrv) across a circuit breaker as a function of the fault current, the limiting inductance and the circuit parameters when a fault occurs near the terminals of the circuit breaker. The fault current limiter (FCL), composed of an inductance, was assumed to be connected at the bus-tie position. This work provides a mathematical expression of the relationship between the rrrv and the limited current that can be used to find out the dependence of the breaking duty upon the circuit parameters. A small increase in the limiting inductance can reduce significantly the rate of rise of the transient recovery voltage, thus resulting in favorable breaking conditions.