Investigation Of Transmission Line Based 3-stage Pulse Generator

Transmission line based multi-stage Blumlein pulser is a new kind of compact high voltage pulse generator, which is charged in parallel and discharged synchronously in series and can generates high voltage pulse of several hundred kilovolts.This system can produce long duration pulse with relatively simple structure, it can be operated repeatedly by switching single spark gap.The cost is low because of the excellent performance of high-voltage cable. A 3-stage Blumlein high-voltage pulse generator using coaxial cable was designed and constructed in this paper.The device is capable of producing upto 100kV voltage pulse under matched load of 300 ohm resistor with pulse duration of 50ns.The basic component of a transmission line based multi-stage Blumlein high-voltage pulse generator is analysised,including the pre_pulse problem and its weaken,the rise time of the main pulse ,the parasitic line impedance Zs and its estimate method.Then the connecting structure and voltage multiplication principle of multi-stage Blumlein pulser was studied.To accurately study the charging and discharging process of the pulse generator, a PSpice circute model of the system was constructed, which was used to simulate the key parameters, including discharging switch inductance, parasitic line impedance and so on and their adverse effect on the voltage gain and pulseshape.The designed 3-stage Blumlein high-voltage pulse generator was carefully tested, which includes the low-voltage test and high-voltage test. The low-voltage test was aimed to validate the design and optimize the pulseshape. After continual amelioration, the pulseshape was pretty good. High-voltage pulse output was achieved from the high-voltage test in the end.