Investigation Of LC-Marx Generator Based On Saturable Pulse Transformer

At present,high power pulse driver has been widely used in many fields such as national defense and civil engineering.Pulsed power technology is developing towards high power,high repetition rate,solid-state and miniaturization.In this paper,a pulse generator based on Saturable Pulse Transformer(SPT)and LC-Marx technology is designed.The preliminary experimental study on the all-solid-state microsecond pulse generator is carried out.The results show that the pulse generator can output quasi-square wave pulse and has the ability of repetition operation.The main work of the paper is reflected in the following aspects:1.Development of saturable pulse transformerDifferent kinds of magnetic materials were compared and analyzed,and Fe-based amorphous was selected as core material by comparison.The parameters of Fe-based amorphous materials were tested and the hysteresis loops of Fe-based amorphous materials were obtained.The data show that the selected core materials basically meet the experimental requirements.The structure of SPT is designed.The high step-up ratio and low saturation inductance of the core are ensured by setting the primary secondary winding reasonably.The parameters of SPT are calculated and deduced,and the parameters of SPT used in the experiment are obtained.2.The development of new LC-Marx generator.The disadvantages of traditional Marx generator compared with LC-Marx generator are analyzed.The advantages of LC-Marx in miniaturization and compactness of the device are presented.The polarity reversal and discharge process of the saturated core LC-Marx charging are analyzed theoretically,and the circuit parameters are explained,which can provide reference for the design of experimental parameters.The LC-Marx circuit is simulated,and the parameters of the saturated core inductance and the isolation inductance of the LC-Marx circuit are analyzed.Charge and discharge isolation simulation and comparison with inductance isolation method.The results show that the isolation effect is better,the stacking efficiency of output pulse voltage is higher,and the rising time of frontier is shorter.3.LC-Marx generator development based on saturable pulse transformer SPT(1)A preliminary validation experiment of a new LC-Marx generator based on SPT is carried out.According to the simulation results,two-stage LC-Marx generator is used to verify the basic operating characteristics of the generator,such as saturation inversion and voltage superposition.When the charging voltage is 300 V and the grounding inductance is 35 u H,the voltage superposition multiple of the two capacitors is 1.57 times.The system has the ability to obtain high voltage output under low voltage input conditions.(2)Experimental research on LC-Marx generator isolated from inductor and high voltage silicon reactor is carried out.By comparing and analyzing the advantages of high voltage silicon stack replacing isolated inductance LC-Marx generator,the research scheme of high voltage silicon stack isolated LC-Marx generator based on SPT is determined,which has many advantages,such as higher output voltage,higher energy efficiency and shorter rising front.(3)The structure of six-stage LC-Marx generator based on SPT is designed,and the test platform is built,and the simulation and experimental research are carried out.The results show that when the charging voltage is 300 V,the peak value of output voltage reaches 18 k V and the superposition multiple of boost voltage is 5.0 times.(4)A preliminary experimental study on the repetition rate of the pulse generator has been carried out.The LC-Marx generator was experimented with 1 Hz repetition rate by replacing the original charging device with repetition rate capability.The experimental results show that the pulse generator works stably at repetition frequency,but the amplitude decreases due to the limitation of the primary charging power.4.Application Research of LC-Marx generator based on photoconductive switch and solid pulse forming lineOperating characteristics of photoconductive switch are studied.It can be used as on-off switch at low voltage because of its general voltage-withstanding characteristics.A kind of photoconductive switch flip-flop is developed,and the experiment platform is set up to trigger the vacuum flip-flop switch and the field distortion switch.The experimental results show that the photoconductive switch flip-flop has low jitter and short rising front,which can stably trigger the main switch of pulse system.The characteristics of solid forming line are studied.The capacitor type solid state pulse forming line is used to replace the energy storage capacitor in LC-Marx for simulation.The bipolar LC-Marx generator circuit is built to verify the experiment.The experimental results show that the capacitive solid-state pulse forming line can replace the capacitor as the LC-Marx energy storage unit.A new scheme of Marx pulse generator based on photoconductive switch and solid pulse forming line is proposed.Two application designs of two pulse generators are put forward respectively for low voltage and high voltage requirements.