Title :
Pulsed electrical discharges in vacuum at cryogenic electrode temperatures
Author_Institution :
Inst. of Electrophys., Acad. of Sci., Sverdlovsk, USSR
fDate :
12/1/1989 12:00:00 AM
Abstract :
A review is presented of recent investigations concerning the effect of cathodes at cryogenic temperatures on the initiation of a pulsed vacuum breakdown. It has been observed that cooling Nb and W cathodes from 300 K to 4.2 K results in a monotonic increase of the critical emission current and the pulsed electric strength of the vacuum gap. This appears to be due to variations of the thermophysical characteristics (resistivity, thermal conductivity and heat capacity) of the cathode on cooling. The superconducting state of an Nb cathode essentially does not affect the vacuum breakdown delay time. Also given are the results of a study of the initiation of a vacuum breakdown between electrodes made of high-temperature superconductors
Keywords :
cathodes; cryogenics; discharges (electric); electric strength; niobium; tungsten; 4.2 K; Nb; W; cathodes; critical emission current; cryogenic electrode temperatures; heat capacity; high-temperature superconductors; pulsed electric strength; pulsed vacuum breakdown; resistivity; superconducting state; thermal conductivity; thermophysical characteristics; vacuum breakdown delay time; Cathodes; Cooling; Cryogenics; Delay effects; Electrodes; High temperature superconductors; Niobium; Thermal conductivity; Thermal resistance; Vacuum breakdown;
Journal_Title :
Electrical Insulation, IEEE Transactions on
