電磁駆動力を受けて平行平板電極の端面間を走行するアークの速度特性

抄録

Experimental investigation was performed on an electromagnetically driven arc burning between the edges of parallel flat electrodes in atmospheric pressure. A pair of parallel flat electrodes having a length of 640mm, a width of 20mm and a thickness of 1.2mm is set up horizontally with a gap length of 13mm. After new electrodes were arranged, the arc was sequentially ignited either 100 or 200 times in interval of 30 seconds. The result revealed that after reaching the local maximum at iteration number N_test of 10-15, the travelling velocity of the arc slightly decreased with an increase in N_test for all of the d. c. arc current la in the range from 36.5 to 117 A. The skipping number N_skip of an anode spot per unit length proved to lessen gradually with Ntest for I_a=36.5 and 48 A and to remain constant for I_a=65, 90 and 117 A. For instance, N_siap decreased from 102 to 80 m^-1 with increasing N_test from 10 to 100 times for I_a=36.5 A, while N_sbp was kept at 36 m^-1 for I_a=117 A. Accumulated amounts M_a of the anode erosion and M_c of the cathode erosion, respectively, were found to rise almost proportionally with N_test for all of I_a and to reach 118 and 65 mg at N_test of 200 times in case of I_a=117 A, respectively.