Spectroscopic measurement of high current vacuum arc plasma in triggered vacuum switch

Summary form only given. The purpose of this experiment is to develop a triggered vacuum switch (TVS) and also to improve understanding of the high current vacuum arc phenomena in the TVS. The TVS used in the experiment has an array of rods of alternate polarity in which a fixed gap spacing is maintained between the rods. The cross section of each rod has trapezoidal shape. A spectroscopic measurement was performed over 20 kA peak current in the center of electrodes, in the vicinity of cathode, and outside electrodes. The electrode material tested was Fe. Measured Fe spectrum range was from 200 nm to 900 nm. Measurement result showed that over 90 percent of the charge states were Fe I and the others were Fe II and Fe III. The electron temperature was determined from the relative line intensity ratio method of Fe II system by assuming the local thermal equilibrium (LTE). The electron temperature at the center of electrodes was measured as 1.5 eV at 26 kA peak current. The electron temperature varied with its peak current. Intensity of spectrum was the highest in the vicinity of the cathode. Further we will also present study result of the diode phenomena in the TVS.