Low-impedance high-power pulsed generator based on forming line with built-in Tesla transformer

In order to meet the application needs of gyromagnetic nonlinear transmission lines, a pulsed power generator is required to output short duration pulses with a fast rising edge in high repetitive-rate mode. In this paper, a low-impedance high-power pulsed generator based on the forming line with a built-in Tesla transformer is explored and developed. The generator includes a 14 Ω coaxial forming line, a SF₆/N₂ gas switch, and a resistive dummy load, which can steadily operate in 100 Hz mode and suits the needs above. The pulsed forming line adopts transformer oil as the insulation medium and has a large shell radius and short length to reduce impedance. It has been verified by CST simulation that a relatively high coupling coefficient (0.93) can be achieved when the length-radius ratio is 3.2. The maximum forming line charging voltage is -600 kV in single-shot mode, while the charging voltage is -520 kV in repetitive-rate mode. The output pulse duration is 13 ns with a 4 ns rising edge, and its amplitude for a 10 Ω load is -220 kV at a repetition rate of 100 Hz. The experimental results showed the feasibility of the low-impedance nanosecond periodically pulsed generator based on an oil forming line charged from the high-coupling Tesla transformer. These efforts expand the technical route of the pulse forming line with a built-in Tesla transformer and set a good foundation for its application in the future.