Current interruption phenomena in HV disconnectors with high-speed opening auxiliary contacts

High-speed opening auxiliary contacts (“whip type device”) is used to enhance the capacitive current interruption capability of air-break disconnectors. Firstly the paper introduces the basic working principle of this device. Secondly a series of laboratory tests are described. The voltages at both sides of the disconnector and the current through the disconnector are measured. The arc images are recorded by a high-speed camera with 1000 frames/s as well. The test data and arc images are studied for both failed- and successful interruptions. Finally, conclusions and remarks are given.