Investigation Of Magnetically Insulated Transmission Line Oscillator And Correlative Technologies

Magnetically insulated transmission line oscillator (MILO) is a relatively new type of crossed field device designed specifically to generate microwave power at the gigawatt level, which is a major hotspot in the field of high-power microwave (HPM) research at the present time.Through the investigation of the theories and the correlative technologies of the MILO, the basic principles and processes for MILO design are systematically presented, according to which, the 1.76GHz compact MILO is designed and manufactured. Under the different experimental conditions, the 1.76GHz compact MILO achieves two different research goals. Furthermore, a 1.2GHz MILO and an X band MILO are explored experimentally, and a novel double-band high-power microwave source is presented. The central contents and innovational work are as follows:1. The theories of the MILO are studied.The studies of the theories of the MILO focus on the beam-wave synchronization condition, the operation principle, the resonance frequency, the beam-wave interaction, the power conversion efficiency, and the dispersion relation. The method of the equivalent circuit is introduced to analyze the resonance circuit of the single-cavity system and multi-cavity system for the first time. The theoretical analyses show that the resonance frequency of the multi-cavity system rests on the resonance frequency of the single-cavity system and the equivalent capacitance. Based on further analysis, an important conclusion that the MILO with four-cavity slow wave structure can be operated effectively and stably is obtained. These research results found a firm foundation for the structural design of the MILO.2. The correlative technologies of the MILO are studied.In the study of the correlative technologies of the MILO, this dissertation investigates the pulsed power technology, the vacuum technology, the structure design and material of the cathode, the material and surface treatment of the anode, the pulse shortening, and a short dipole antenna. These research results found a firm foundation for the system design of the MILO.3. The 1.76GHz compact MILO is studied in detail.In the study of the 1.76GHz compact MILO, according to the research results of the theories and the correlative technologies of the MILO, the basic principles and processes for MILO design are systematically presented, according to which, the 1.76GHz compact MILO is designed and then optimized with KARAT code. Under the different simulation conditions, the output parameters are better than relevant research goals. When the voltage is 500kV, the pulse duration is 50ns, and the current is 48.3kA, HPM is generated with a power of 2.53GW, a pulse duration of 27ns, a frequency of 1.76GHz, a power conversion efficiency of 10.5%, and an impedance of 10.4Ω. When the voltage is 525kV, the pulse duration is 80ns, and the current is 50.2kA, HPM is generated with a power of 2.70GW, a pulse duration of 51ns, a frequency of 1.76GHz, a power conversion efficiency of 10.5%, and an impedance of 10.4Ω.Under the different experimental conditions, the measured parameters are also better than the relevant research goals. When the voltage is 530kV, the pulse duration is 50ns, and the current is 51kA, the experimental results show that the radiated microwave power is above 2.35GW, the pulse duration is above 24.8ns, the frequency is 1.775GHz, the power conversion efficiency is above 8.7%, and the impedance is 10.4Ω. When the voltage is 550kV, the pulse duration is 80ns, and the current is 53.2kA, the experimental results show that the radiated microwave power is above 3.2GW, the microwave pulse duration is above 45ns, the frequency is 1.775GHz, the power conversion efficiency is above 10.9%, and the impedance is 10.3Ω. Compared with the current typical MILO devices in the world, its technical performances are obviously superior in microwave power, compact grade, power conversion efficiency and energy conversion efficiency.In the latter experiments, when thel.76GHz compact MILO is driven by a long pulse accelerator or a rep-rate operation accelerator, the technical performance is explored. The research results show that the degradation of vacuum conditions caused by outgassing of the cathode is the key reason which affects the technical performance. At last, different cathode material is explored.4. In the further study, three different HPM sources are studied.In the experiments of the 1.20GHz integrative MILO, the experimental results show that the radiated microwave power is above 2.3GW, the microwave pulse duration is about 30ns, the frequency is 1.20GHz, and the power conversion efficiency is above 8.9%, when the voltage is 550kV, and the current is 47kA. In the study of the X band MILO, the causes of the pulse shortening occurred in the experiments are analyzed and pointed out. At last, a noveldouble-band high-power microwave source is presented and investigated in detail, a better simulation results is obtained.