Dynamic Dielectric Recovery Synergy of Hybrid Circuit Breaker With CO2 Gas and Vacuum Interrupters in Series

This paper investigates the dynamic dielectric recovery synergy (DDRS) of hybrid circuit breakers (HCBs) with CO
₂
gas and vacuum gaps in series. The interaction between the vacuum arc and CO
₂
gas arc is simulated by the continuous transient arc model and Mayr arc model. The simulation results indicate that the extra methods, for example, dividing capacitors, are needed to obtain optimal DDRS of HCB. The prototype of HCB and the test circuit are established. The influence of the coordination of arcing time, dividing capacitors, and the CO
₂
gas pressures on the transient recovery voltage (TRV) distribution and the breaking capacity is investigated. The differences of HCBs with SF6 gas and CO
₂
gas are also compared. According to the results, favorable DDRS in HCB can be obtained in the condition that the vacuum gap endures the initial TRV while the following major TRV distribution is mainly depended on the dynamic dielectric in CO
₂
gas gap. However, the dynamic dielectric recovery of CO
₂
gas gap is limited by the structure of rotating arc CO
₂
gas interrupter in this paper. In the future, the interruption capacity of HCB based on CO
₂
gas can be improved by synergy control, as the development of CO
₂
gas circuit breakers.