Numerical study on arc discharge characteristics in double- and single-flow-type gas circuit breakers

摘要

We investigate the effect of exhaust gas flow on the arc discharge characteristics by means of three-dimensional numerical analyses for double- and single-flow-type gas circuit breakers (GCBs). The arc voltage of the double-flow type becomes high compared to the single-flow type when a cooling gas flows from puffer chamber to the downstream channel. The arc voltage of double-flow-type GCB increases by approximate to 20% during high current of over several kiloamperes. The increase in arc voltage caused by double-flow exhaust depends mainly on the extension of arc discharge length. The arc conductance per unit length remains unchanged. The arc current decreases below a few kiloamperes, and then the pass of the arc discharge gets much longer and penetrates deep into the tulip contact because of the strong exhaust flow to the tulip contact side in the case of the double-flow-type GCB. (c) 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.