Development of Vacuum Interrupter with AMF contacts for high voltage circuit breaker

Nowadays, high-voltage vacuum circuit breakers (VCBs) have being developed to reduce the impact of SF6 gas to the environment. Until now, many high-voltage VCBs have been reported to apply into the transmission line. In the case of rating voltage of 72.5kV, SF6 free VCB and Switchgear are developed already. In this paper, a new 72.5kV Vacuum Interrupter (VI) was presented. The axial magnetic field (AMF) type contact structure of VI was applied to ensure the current interrupting performance with long gap. The dielectric test and the temperature rising test was carried out to evaluate the performance of prototype VI. The temperature rising test was carried out two times with SF6 gas and Dry-air. The test of prototype VI is still ongoing. Therefore, the current interrupting test results could not be mentioned here.