ISHII Akira Toshiba, Env.Equipment Eng.Lab., Researcher, 環境機器開発研究所, 研究員
IBUKA Shinji Tokyo Institute of Technology, Faculty of Eng., Research Associate, 工学部, 助手 (70262277)
|Budget Amount *help
¥9,900,000 (Direct Cost : ¥9,900,000)
Fiscal Year 1996 : ¥1,300,000 (Direct Cost : ¥1,300,000)
Fiscal Year 1995 : ¥8,600,000 (Direct Cost : ¥8,600,000)
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.