Semiconductor opening switch generator with a primary thyristor switch triggered in impact-ionization wave mode.

Abstract

The results of the investigation involving a thyristor switch triggered in the impact ionization wave mode are presented. This switch is intended for operation as a primary switch in a nanosecond pulse generator with a semiconductor opening switch (SOS). The thyristor switch is based on commercial low-frequency tablet thyristors stacked in a joint assembly of up to 6 pieces connected in series. At a charging voltage of 2-12 kV and switching energy of up to 16 J, the switch operates with a discharge current of up to 8 kA, a current rise rate in the range from 14 to 54 kA/μs, and a switching efficiency of ∼0.9. It is shown that an increase in a voltage rise rate on thyristors at the triggering stage reduces energy loss in the thyristor switch during the current flow. The SOS pumping circuit contains one magnetic element-a pulse transformer, which simplifies the generator and increases its efficiency. The SOS generator has an output voltage of up to 300 kV and a peak power of up to 250 MW with a pulse duration of ∼50 ns. The thyristor switch in the generator operates at a voltage of 12 kV and provides current flow with the amplitude of up to 7.5 kA with a duration of ∼500 ns and a current rise rate of ∼54 kA/μs. The pulse repetition frequency of the generator is 1 kHz in the burst mode of operation.