【作者】 杨实；

【导师】 钟辉煌；

【作者基本信息】 国防科学技术大学 ， 电子科学与技术， 2010， 博士

【摘要】 国防和工业应用上的需求促进脉冲功率技术向高重频、高平均功率、固态化和紧凑化方向发展。基于磁开关和带状线的长脉冲、超低阻抗脉冲发生器是符合这一发展方向的重要候选者之一。本文通过对卷绕型带状脉冲形成线和磁开关两大核心子系统进行理论分析、工程设计和实验研究,完整地提出了长脉冲、超低阻抗脉冲发生器设计方案和设计方法,研制出一台长脉冲、超低阻抗脉冲发生器。本文的研究结果为长脉冲、超低阻抗、固态化脉冲发生器的应用研究奠定了基础,对此类脉冲发生器的研制具有重要的指导意义。论文的研究内容主要包括以下几个方面:1.设计了一台固态化的卷绕型带状脉冲形成线,其具有长脉冲和超低阻抗的特点,对其进行了理论分析、制作加工和实验研究。通过保角变换的方法求解了带状脉冲形成线的特性阻抗。制定了卷绕型带状脉冲形成线制作流程,并设计制作了一台特性阻抗0.5 ?,电长度115 ns,以DMD膜为绝缘介质的固态化带状脉冲形成线。该形成线卷绕后尺寸为Φ311mm×400 mm。应用设计的多通道轨道开关对形成线性能进行了测试,在匹配负载上获得了电压17.8 kV,脉宽(FWHM)约270 ns,上升沿约20 ns的准方波脉冲,输出功率为634 MW。结合形成线特点,设计了一种中间输入结构。应用数值模拟的方法验证了该输入结构在保证输出波形质量的前提下,可有效地缩短形成线充电时间,提高形成线耐压水平。2.基于理论分析和数值模拟结果,制定了环形磁开关设计流程。运用该流程,设计制作了一台40 kV级环形磁开关。该磁开关以铁基非晶磁环为磁芯,在实验中将40 kV,10μs脉冲压缩为39 kV,2.36μs,并在10 Hz重频下可稳定运行。设计并制作了一台具有低饱和电感的跑道形磁开关。该磁开关为单匝平板绕组,跑道形磁芯,饱和电感仅约30 nH,保证了输出脉冲的快上升沿。以此跑道形磁开关替代轨道开关作为主开关,实现了脉冲发生器主开关的固态化。运用单级磁脉冲压缩实验平台,设计了一种磁芯动态磁滞回线的测量方法。该方法适合于脉冲磁化条件下,磁性材料的特性参数测量和磁滞回线的绘制。此外,该测试平台可通过改变回路中电容和电感参数,方便地改变输出脉冲的伏秒积,从而测试磁芯在不同磁化条件下的动态特性。3.提出了一种新型长脉冲、超低阻抗脉冲发生器技术方案。该方案具有固态化、高重复频率、高平均功率等优点。脉冲发生器由初级能源、脉冲变压器、磁脉冲压缩器、带状脉冲形成线、主开关和负载组成。将已研制完成的核心子系统联合,组成长脉冲、超低阻抗脉冲发生器。对脉冲发生器进行了全电路模拟和实验研究。在0.5 ?匹配负载上进行实验得到:单脉冲运行时,负载上得到电压17.8 kV,脉宽(FWHM)约270 ns的准方波脉冲;在重复频率7 Hz运行时,负载上得到电压14 kV,脉宽(FWHM)约285 ns的准方波脉冲,脉冲发生器工作稳定,输出脉冲波形一致性高。更多还原

【Abstract】 Defense and industrial applications have stimulated intense interests in pulsed power technology towards high repetition rate, high average power, all solid-state and compact structure. The long pulse, ultra-low impedance pulse generator based on magnetic switch and strip line investigated in this dissertation is an important candidate in this field.In this dissertation, a long pulse, ultra-low impedance pulse generator is developed based on the theoretical analysis, engineering designs, and experimental investigations of the two key subsystems which are a rolled strip pulse forming line (PFL) and a magnetic switch. These efforts are the ground for the development of a long pulse, ultra-low impedance and all solid-state pulse generator, and provide a significant reference for the research on this kind of pulse generator. The detailed contents and innovative work are as follows.1. A solid state, rolled strip pulse forming line with long pulse and ultra-low impedance is designed and is investigated both theoretically and experimentally. The characteristic impedance of the strip pulse forming line is obtained by using the conformal mapping methods. The design procedure of a rolled strip pulse forming line is worked out. And a rolled strip PFL with characteristic impedance of 0.5 ?, electric length of 115 ns was designed and manufactured. We use the DMD film and copper as the dielectric and conductor of the strip PFL separately. The dimension of the rolled strip PFL isΦ311mm×400 mm. A multi-channel rail gap switch for connecting to the strip PFL is designed and manufactured with the virtues of small volume and low inductance. In the PFL experiment, a quasi-square pulse of 17.8 kV, 270 ns (FWHM) on the matched load of 0.5 ? is obtained and the output power is 634 MW. A novel strip pulse forming line with a middle input structure is proposed. Compared with the conventional input structure, the middle input structure can reduce the duration of the charging and increase the electric strength of the strip line obviously on condition that the output pulse is a quasi-square wave.2. Based on the results of theoretical analysis and simulation, the design procedure of a toroidal magnetic switch is worked out. A 40 kV class magnetic switch is designed and manufactured according to the procedure. The core of the magnetic switch was stacked by the Fe-based amorphous magnetic rings. In the experiment, a pulse is compressed from 40 kV, 10μs to 39 kV, 2.36μs. And the magnetic switch can operate stably at 10 Hz repetition rate. A magnetic switch with low saturated inductance is designed and manufactured. The number of turns is one and made of copper plate. This structure can reduce the saturated inductance of the magnetic switch to about 30 nH. The magnetic switch is used as the main switch by replacing the rail gap switch to realize the solid state of the main switch.A novel testing method for the hysteresis cycle of the magnetic core has been proposed based on the single magnetic compression experimental platform. This method is applicable to the measurement of characteristic parameters and hysteresis cycle of magnetic material under the pulsed magnetization condition. In addition, this system can change the volt-second product of the output pulse conveniently by changing the parameters of the capacitor and inductor to measure the dynamical characteristics of the magnetic core in different magnetization condition.3. A novel long pulse, ultra-low impedance pulse generator with the advantages of solid state, high repetition rate and high average power is proposed. It comprises primary energy system, pulse transformer, magnetic switch, rolled strip PFL, main switch and load.In summary, based on the two key subsystems mentioned above, the long pulse, ultra-low impedance pulse generator is developed. The pulse generator is investigated by circuit simulation and experiment. On a 0.5 ? matched load, it can generate an output pulse with voltage of 17.8 kV, duration (FWHM) of 270 ns and rise time about 20 ns in the single shot mode. In the rep-rate mode, the experimental results show that the pulse generator can operate stably at 7 Hz repetition rate, with the output pulse of 14 kV, duration (FWHM) of 285 ns.更多还原