Effect of Additional Capacities on Transients Recovery Voltage in the Short – Line – Fault Regime

When short-circuits fault clearing at the contacts of high-voltage circuit breakers (CB), a transient recovery voltage (TRV) appears. The largest contribution to TRV bring in by the component of the recovery voltage (RV) between the contact of the CB and the earth from the side of electric transmission lines, which has the character of sawtooth wave. Being superimposed on the main component of the RV from the voltage source, these high-frequency sawtooth waves cause a very high rate of rise of the TRV and thus make it difficult to current interruption of the short circuit current by CB. As world experience shows, it is possible to prevent such accidents with the help of additional capacities installed between the line terminals of the CB. Assessment the effect of additional capacity on the rate of rise of the TRV in demand on the contacts of a 110 kV SF6 CB, by a software package EMTP – RV was designed calculated mathematical model electromagnetic transients within the parameters interrupting chamber.