High-frequency reignition current and its influence on electrical durability of circuit breakers associated with shunt-Reactor current switching

Very-high-frequency and high-peak reignition currents were measured in shunt reactor banks rated at 33 kV 40 MVA during breaking operations of a gas circuit breaker (CB). To measure those kinds of high-frequency transients in reactor circuits in service, a noninvasive method of measuring was proposed using Rogowski coils and capacitive coupled antennas. Some combinations of metals in an electrical collector used in CBs tend to get severely eroded by the high-frequency reignition currents. The paper also proposes a test circuit that can yield high-frequency reignition currents to evaluate the electrical durability of CBs.