Influence of Different Factors on the Interruption Characteristics of Paralleled of High-Voltage SF_6 Circuit Breakers with a Highly Coupled Split Reactor

摘要

Paralleled high-voltage SF_6 circuit breakers with a highly coupled split reactor (HCSR) have an excellent interruption performance, because it is expected that this structure could realize the function of automatic current-sharing when the current flow through both branches and automatic cunent-limiting when the current flow through only one branch. In this paper, a mathematical model had been built for this interrupting device by coupling the equivalent circuit equations into the magneto-hydro-dynamics (MHD) arc model. The influence of different factors including different operation moments, different filling pressures and different inductances are investigated. The dielectric recovery strength after the interruption processes is also investigated. The simulation results show that the paralleled high-voltage SF_6 circuit breakers with a highly coupled split reactor have excellent interruption performance. The automatic current-sharing and current-limiting functions of the HCSR under different interruption conditions all show excellent performance, and the 252 kV paralleled SF_6 circuit breakers with HCSR has successfully interrupted 252 kV/101 kA short circuit current in state laboratory of China recently.