573 / 2017-05-16 05:51:39

A Study on Improvement of Low Current Interruption Performance for Self-Blast Circuit Breaker

14407,14408,4225

This paper shows us improvement of low current interruption performance for 145kV Self-Blast Circuit Breaker. The self-blast circuit breaker have been developed to reduce mechanical energy by building up the pressure of arc extinguishing gas flow from the heat of the arc itself. Unlike puffer type, Breaking performance for self blast type are influenced by various factors inside interrupter, such as the nozzle structures, breaking current and so on. These days, particularly, it has been difficult to secure a low current breaking performance as the breaker has been compacted. The low current interruption is 10% to 30% of the rated interruption current, but the transient recovery voltage after the current zero is relatively high than high current one. Therefore, a complex analytical method is needed to secure the low current breaking performance and to improve the performance by using the limited gas flow inside the interrupter parts. In this paper, we have studied a method for improving the performance with various design parameters using computational fluid dynamics (CFD) programs and high power laboratory test.