Influence of Paralleled Capacitor on Paralleled High-voltage SF₆ Circuit Breakers with Highly Coupled Split Reactor

Paralleled high-voltage SF₆ circuit breakers with a highly coupled split reactor (HCSR) have the potential application for the high fault current interruption. Short-circuit current breaking tests showed that the current-sharing was effective. However, there might be difference in the operation moments or the phenomenon of current-limiting interruption. In order to further improve the interruption reliability of this interrupting device and avoid the current-limiting interruption, a circuit model and an arc model were developed through the Simulink module of the MATLAB. The influence of capacitors paralleled to the breaks on the interruption process was investigated. It was found that the paralleled capacitor was constructive to deduce the rising rate of the recovery voltage, thereby realizing the current-sharing interruption. Morever, relevant experiments were carried out. A capacitor of 0.277 μF was paralleled to one of the paralleled breaks and reliable current-sharing interruptions were implemented. The research results are constructive to the development of this interruption device.