Investigation and Evaluation of Solid-State Marx Pulse Generator Based on 3-D Busbar

SiC-MOSFET has been widely used in nanosecond pulse power generators due to its excellent switching characteristics. The solid-state Marx generator using SiC-MOSFET has the advantages of modularity, flexible adjustment, and economic reliability. However, due to the limitation of the busbar loop's parasitic inductance, the excellent switching characteristics of SiC-MOSFETs have not yet been fully utilized in solid-state Marx. This article discusses the PCB wiring structure of the single-module of solid-state Marx and the influence of its superimposed spatial distribution parameters on the output pulse waveform. The principle of 3-D busbar structure and mutual inductance cancellation method to reduce the parasitic inductance of pulse busbar loop is proposed. And verify the above principle through electromagnetic simulation and four-stage superposition experiment. The parasitic inductance of the busbar loop is less than 4 nH. The voltage edge of the output pulse is further reduced, the current rise/fall speed is increased by about 2.3 times, and the switching voltage overshoot is reduced by 80%. And the proposed structure effectively suppresses the gate bounce and improves the solid-state Marx pulse characteristics. Finally, the stability and reliability of the system are improved too.