Double break vacuum circuit breaker — A brief overview

摘要

In Modern Medium Voltage Electric Power system, Vacuum Interrupters are trusted as most reliable, cost efficient & compact devices used for Switching; whereas SF6 circuit breakers are most popular in High Voltage / Extra High Voltage / Ultra High Voltage range of Electric Power System. However, Kyoto Summit in 1997 classified SF6 as potential green house gas due to its longer life span (more than 3200 years). Although it is irreplaceable as an arc quenching medium in High Voltage Switchgear in present scenario, an attempt should be made to reduce its consumption & emission in atmosphere. This necessitates extension of Voltage Range for Vacuum Circuit Breakers up to the High Voltage / Extra High Voltage and Ultra High Voltage Levels in upcoming future. While making current interruption safer for human's future generation, use of these VCBs provides an amenity of simple construction, easier maintenance, and consequently longer operational life of the device. This paper overviews the necessity of series connected vacuum switchgear, it also states advantages of multiple breaks over single break and the main focus shall be on voltage distribution across two VIs in a double break vacuum circuit breaker.