Solid-State IGBT/SOS-Based Generator with 100-kHz Pulse Repetition Frequency

Summary form only given. IGBT/SOS-based solid-state generator with 100-kHz pulse repetition frequency in burst mode of operation has been developed and experimentally studied. Ultra-fast IGBT transistors switch the primary capacitive store, and energy is transferred to the pumping capacitor via the pulsed transformer in about 1.5 mus. Current of this process passes via the SOS and insures its forward pumping. After the pulsed transformer ferrite core saturation the reverse current reaches its maximum value of 200-300 A in about 200 ns. At this instant the SOS cuts off the current in about 5 ns that leads to output pulse formation across external load. Across external resistive load from 100 Omega to 1 kOmega the generator forms quasi-rectangular pulses with ~ 70-ns FWHM and 20 to 80 kV in amplitude. Maximum peak power is equal to 8.5 MW across the resistive load of 250 -500 Ohm. The pulse amplitude is within 50 -60 kV with the pulse energy of about 0.5 J and total efficiency of 70%. In burst mode of operation with 100-kHz PRF the output average power attains 50 kW. To decrease pulse width and increase peak power additional magnetic compression stage has been used. In this case the reverse current through the SOS is about 660 A in amplitude and cutoff time is about 1 ns. Across resistive load of 97 Omega the output peak power reaches 40 MW (62-kV peak voltage) with FWHM of 4-5 ns. Electrical circuit diagram and principle of the generator operation as well as experimental results obtained are described. The results of numerical simulation of the SOS diode operation are presented also.