High Power and High Repetition Frequency Nanosecond Marx Generator Based on Avalanche Transistor With Triggering Acceleration Circuit

The high voltage nanosecond pulses with high pulse repetition frequency (PRF) and narrow pulse width are widely used in high power applications. The M×N-stage Marx-bank circuit (MBC) based on the avalanche bipolar junction transistors (ABJTs) combines the advantages of simple construction and high output amplitude, making it an effective pulse generator for the above requirements. However, PRF of traditional M×N-stage MBC is not improved effectively due to the poor reliability of ABJTs at 1-stage. In this work, the vulnerable properties of ABJT which is at first-stage and triggered by a slow voltage ramp are analyzed and explained by simulation and experiment. On this basis, a modified 4×12-stage MBC with a triggering acceleration circuit (TAC) is proposed. The reliability of the most failure-prone ABJT in 4×12-stage MBC is improved effectively by increasing triggering speed of the voltage ramp generated from TAC. Moreover, the influences of the components in MBC-TAC on the output characteristics are further analyzed and the high PRF and high reliability are verified. The 4×12-stage MBC-TAC achieves an output amplitude of 5.1 kV, a rise time of 1.57 ns, a pulse width of 4.07 ns, and a PRF of 200 kHz. This investigation and improvement of MBC-TAC provides a reference for the applications of MBCs based on ABJTs.