Fast High Voltage Pulse Generator with Nonlinear Transmission Line

为了将快速高压脉冲发生器应用于工业应用，必须建立一种高可靠性、高重复运行率的全固态半导体脉冲发生器。然而，传统的半导体开关存在开关操作缓慢的缺点。在本研究中，我们尝试将脉冲锐化器与非线性传输线结合使用，并成功获得了可使用半导体开关器件构建的耐电压大于10kV的快速脉冲发生器。首先，我们研究了非线性传输线的特性，如阻抗匹配和能量传递比，与市售的陶瓷电容器。其次，我们制造了具有高耐压和强非线性的陶瓷电容器，并建立了烧结条件，如温度，成分和大气。此外，我们还研究了陶瓷电容器在高外加电压下的特性，找到了实现高压非线性传输线的途径。利用数值电路分析研究了电容器的损耗，并明确了建立高能效存在许多问题。然后，我们测试了半导体开关器件的SI晶闸管。由于SI晶闸管的快速开关特性迄今尚未研究，我们利用电容放电电路对其进行了测试。因此，已经明确的是，SI晶闸管可用于利用最佳栅极驱动器和串联堆叠操作的快速脉冲应用。在这项研究中，我们成功地工作了5个堆叠的SI晶闸管，工作电压范围高达15kV。

To apply a fast high voltage pulse generator to industrial applications, it is indispensable to establish an all solid state semiconductor pulse generator with high reliability and high repetitive operation rate. However, conventional semiconductor switches had a drawback of slow switching operation. In this study, we have attempted a utilization of a pulse sharpener with nonlinear transmission lines, and successfully obtained the fast pulse generator with more than 10kV withstanding voltage, which can be constructed with semiconductor switching devices. At first, we have investigated the characteristics of the nonlinear transmission line, such as impedance matching and energy transfer ratio, with commercially available ceramic capacitors. Secondary, we have manufactured ceramic capacitors with high withstanding voltage and strong nonlinearity, and established sintering conditions, such as temperature, composition and atomosphere. Moreover, we have examined the characteristics of ceramic capacitors under high applied voltage, and found a way out of realizing high voltage nonlinear transmission lines. The losses of the capacitors were also investigated utilizing a numerical circuit analysis, and it has been cleared that there are many problems to establish high energy efficiency. Then, we have tested SI thyristors for semiconductor switching devices. Since the fast switching characteristics of SI thyristors were not investigated so far, we have examined them utilizing a capacitor discharging circuit. Consequently, it has been cleared that the SI thyristors are available to fast pulse applications utilizing optimum gate drivers and series stacked operation. In this study, we have successfully operated stacked five SI thyristors with operating voltage range of up to 15kV.