Abstract:

For the high voltage DC contactor with the differentiated development according to the technical characteristics,under the premise of unpressurized design,the DC arc breaking technology of air medium is studied by comparing the breaking waveform from the different angles such as contact opening distance,arc extinguishing grid,arc driving magnetic field,breaking speed and arc burning gas flow.The comparative analysis of the results shows that the reasonable layout of gas channel and arc extinguishing grid is the key to the extinction of arc,the arc driving magnetic field in a certain range can ensure the effective stretching of the arc,and a certain contact opening distance and breaking speed can effectively control the arc burning time.

Key words: high voltage DC contactor, arc breaking, magnetic field, arc extinguishing chamber, air medium