TECHNOLOGICAL-PROGRESS OF AXIAL MAGNETIC-FIELD VACUUM INTERRUPTERS

New methods have been developed for investigating vacuum arcs applied to the improvements of vacuum interrupter electrodes. Electrode surfac e temperature measurements reveal the anode surface melting condition at the current interruption and its influence on interruption capabili ty, and a digital image processing technology gives us a clear underst anding of the arcing phenomenon, Measurements and test results have sh own the advantages of axial magnetic field electrodes in increasing th e interruption capability of vacuum interrupters. It is confirmed that axial magnetic field electrodes are superior to other types of electr odes, and we believe that these new investigation methods promote the optimization of the electrode structure and the realization of higher voltage and current rating vacuum interrupters.