Control of Trichel pulses of corona by geometric and gasdynamic factors

Summary form only given. Upon applying of step of high voltage that is over an inception one, the ignition of a negative corona is accompanied by a sharp splash of discharge current with a pulse duration of about 10/sup -7/. As a rule, for electropositive gases (N/sub 2/, Ar, etc.) the corona current falls after the splash and goes to the stationary value that is much smaller than the one for initial pulse. For electronegative gases (air, O/sub 2/, etc.) in which electrons are turned into negative ions, instead of stationary state the pulsed regime of corona with regular splashes of discharge current is established and named as Trichel pulses. The physical condition for existence of regular Trichel pulses lies in the fact that a displacement current of the corona has to approach the conductivity current in this regime. This condition is easily devised for corona in air, O/sub 2/ in which the negative ions are the main carriers of charge through the interelectrode gap. In the case where the electrons are the major carriers of charge (N/sub 2/, Ar, etc.) the reduction in the contribution of conductivity current to the total current can be reached only for corona with interelectrode gap more than 15-20 cm.