Search

This paper aims to investigate the anode modes of vacuum arc at different opening speeds, especially at a high opening speed that exceeds 3 m/s. The butt contacts made of CuCr30 and CuCr50 with a diameter of 15 mm are used. Experiments are conducted at the current of 3.3, 4.4, 5.5, and 6.3 kA with a frequency of 50 Hz. An electromagnetic repulsion actuator provides the average opening speed from 1.7 to 3 m/s. The experimental results show that the number of droplets splashing into electrodes increases as the arc current increases, while a higher opening speed decreases the droplets. A higher opening speed will reduce the transferred charge before the anode spot type 2, and a higher Cr content increases the transferred charge before the anode spot type 2. Increasing opening speed will decrease the starting time of anode spot type 2, but it increases the gap distance when anode spot type 2 appears. Meanwhile, the increase in Cr content delays the formation of anode spot type 2. [ABSTRACT FROM AUTHOR]

In this paper, a numerical simulation on the interaction between the double cathode spot craters in the vacuum arc is carried out. By establishing a double-cathode spot ablation model, the crater development process when two spots coexist is simulated, and the formation mechanism of cathode spot groups is analyzed. The simulation results show that the two cathode spots appearing on the flat electrode would squeeze each other to form a liquid metal ridge, which changed the ablation morphology of the cathode spots. When the double-spot arc craters appear simultaneously, the metal ridge will be squeezed into a straight line, otherwise, when the spots appear one after another, the liquid metal ridge will shift toward the side of the spot that appears first. The relative experimental results are adopted to compare with the simulation results. By comparison, it is found that the morphology of the multi-spot crater in the experiment is in agreement with the simulation results. [ABSTRACT FROM AUTHOR]