| Because of the important military merit and civil foregrou, repetitive pulse-power generator is one of the important study direction for the pulse power technology. The compact repetitive pulse-power generator is one of the kernel technologies of high-power microwave (HPM). More attention has been progressively paid to the pulse power generator which based on the direct driving technology as one of the primary technical approaches for achieving the compact and repetitive of pulse-power generator, In this dissertation, the pulse power generator with a10-stage Pulse Forming Network-Linear Transformer Driver (PFN-LTD) module has been developed based on the detailed theoretical analysis, circuit simulations and basic experimental study. The designed idea and studied result are instructive for the further development of this kind of pulse power generator, and also set a good foundation for the realization of higher performance as well as more extensive applications. This dissertation mainly consists of the following aspects:The technological background and recent studied results related to direct driving technology is introduced. The key technology and developing direction about PFN-Transformer and PFN-Marx based on direct driving technology is discussed. At the same time, the potential technology approaches for achieving the compact and repetitive of pulse-power generator is analysed. The accelerator based on water-dielectric helical pulse forming line is theoretical analysed and designed. With considering the merit and drawbacks of the linear transformer and its application, the compact repetitive pulse power generator based on the PFN-LTD technology is firstly proposed. The designing goal is working voltage400-500kV, peak power8～10GW, pulse width200ns, working frequency50Hz.Basing on discussing the requirements on pulse forming module for PFN-LTD technology, the drawbacks of the pulse forming line (PFN) with solid/liquid dielectrics for forming long pulse and the pulse forming network with film capacitors for forming short pulse is detailed analyzed. A high energy density middling-high voltage pulse forming network which suit slowly charging was designed with a ceramic capacitor with low self-inductance. The experimental results indicate that the rise time of the high voltage pulse is less than40ns; the pulse width is about220ns when the matching load is1Q. The designed PFN can satisfy the needs of compact and lightweight application. The experimental results also indicate that the rise time of the high voltage pulse which is generated by the Blumlein pulse forming module is about50ns and the pulse width is about230ns when the matching load is2.5Ω. The charging voltage of the Blumlein pulse forming module is44kV. It set a good foundation for developing the compact pulse power generator. Through the finite element analysis and simulation, the induction of the switch part and the load part of PFN was simulated and studied. Basing on the analysis of the simulating result, an improved design of the switch part structure is introduced.The primary effecting factor for the rise time of the pulse which is output by the LTD is analyzed. The performance of the magnetic core effecting on the quality of the pulse is also discussed. Considering the nanocrystalline magnetic materials with relatively high saturation flux density, low loss and high Curie temperature has shown promise for significantly improving energy transfer efficiency and realize pulse power generator compact. A test stand is developed to measure the performance of the nanocrystalline magnetic materials which is made in China. Based on the test stand, a series of experiment are carried out for testing the B-H curve, pulse permeability. The mean length magnetic path and effective core area effect on energy transfer efficiency is studied. The insulated ability of oxidated film of the magnetic core which is natural formed also measured. The experimental results are instructive for the homemade nanocrystalline magnetic materials used in the LTD, inductive add, magnetic switch and pulse transformer.In this paper, the requirement of pulse power generator basing on PFN-LTD technology on the switch is analyzed. For switch delay of normal distribution, the effects switch jitter and single waveform's rise time on the rise time of resultant waveforms are discussed when the multiple work synchronously. Based on the detailed investigation of the high power switch, the Triggered Vacuum Switches RUV-31, cold cathode thyratron TPI-10k/50and trigger switch GXG are choose primarily. A test stand and there trigger system are designed to measure the performance of switches. The experimental results showed that cold cathode thyratron TPI-10k/50with low jitter, low inductance and high dI/dt. It quite well meets the demand of the pulse power generator basing on PFN-LTD technology. Based on the trigger device, the research of trigger performance of TPI1-10k/50was done, including the influence of heater voltage, trigger current and direct pre-ionization current. At last, this switch worked under the condition of:voltage of40kV, current of16kA, pulse width of200ns, Pulse repetition rate of20Hz-50Hz. The jitter of TPI1-10k/50is about2ns. The experimental results are beneficial for the commercial middling-high voltage used in the pulse power generator for improving the stability and reliability.Through the theoretical analysis and simulation, the effects of impedance on the voltage transfer efficiency, energy transfer efficiency and peak power transfer efficiency when PFN discharges to the load directly and through LTD are discussed. Based on the foregoing study,10-stage PFN-LTD generator is designed and researched. According to the characteristic of the pulse power generator, we designed and manufactured high-frequency switching power supply, control system, measurement system, and restoration system. The dimension of the pulse power generator is about1.4mx2mx1.3m. The total weight is about two ton. The experimental results shown at a34kV charging voltage, the10-stage PFN-LTD generator can operate stably at1Hz, producing an output pulse of276.6kV pulse voltage,11.6kA pulse current,223ns pulse width,80ns rise time.
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