Dielectric Recovery Characteristics after High-Frequency Current Interruption in Vacuum Circuit Breaker

摘要

When the contacts of circuit breaker are opened just before current zero, the gap between contacts will still be very short. Therefore, it cannot withstand recovery voltage between the contacts. In such a case, multiple reignition is likely to take place. Many investigators had tried to clarify this phenomenon, and many reports have been published. However, high-frequency current interruption and dielectric recovery characteristics are related to some parameters (value of current, arc time, and so on). In addition, arc phenomenon has also been implicated. Hence, it is difficult to understand this phenomenon accurately. In this paper, we conducted dielectric recovery test and high-frequency current interruption test. Further, we conducted observation experiment using vacuum chamber in order to investigate the effect of small dc current. At the end, we calculated plasma density in the electrodes after high-frequency current interruption by considering the result of observation experiment and dielectric recovery test. (C) 2016 Wiley Periodicals, Inc.