Influence of Gap Distance on Vacuum Arc Characteristics of Cup Type AMF Electrode in Vacuum Interrupters

摘要

The greenhouse effect of SF6 is a great concern today.The development of highvoltage vacuum circuit breakers becomes more important.The vacuum circuit breaker has mini-mum pollution to the environment.The vacuum interrupter is the key part of a vacuum circuitbreaker.The interrupting characteristics in 'vacuum and arc-controlling techniue are the mainproblems to be solved for a longer gap distance in developing high voltage vacuum interrupters.To understand the vacuum arc characteristics and provide effective technique to control vacuumarc in a long gap distance,the arc mode transition of a cup-type axial magnetic field electrode isobserved by a high-speed charge coupled device (CCD) video camera under different gap distanceswhile the arc voltage and arc current are recorded.The controlling ability of the axial magneticfield on vacuum arc obviously decreases when the gap distance is longer than 40mm.The noisecomponents and mean value of the arc voltage significantly increase.The effective method forcontrolling the vacuum arc characteristics is provided by long gap distances based on the testresults.The test results can be used as a reference to develop high voltage and large capacityvacumn interrupters.