Switching of Reactive Loads with High Voltage Vacuum Circuit Breaker

For high‑voltage applications, the interaction between the system and the vacuum circuit breaker is strongly influenced by intrinsic vacuum physics, particularly when switching reactive loads such as shunt reactors or capacitive cables, lines, and capacitor banks. This paper summarizes the state of knowledge. Investigations presented in this paper aim to close the existing gaps through representative tests on various vacuum circuit breaker types.

Capacitive switching tests investigated how field emission affects the capacitor bank performance (such as back‑to‑back application), where successful results were achieved in accordance with IEC 62271‑100. Inductive load switching studies focused on shunt reactors, where measures, such as controlled switching and additional line‑to‑ground capacitors, enabled reignition‑free operation. Overall, simulations and test results confirm that vacuum circuit breakers are suitable for reactive load switching up to ultra‑high‑voltage levels such as 420 kV.