300kV/3ns脉冲电压源的研制

Development of 300 kV pulse source with 3 ns risetime

研制了一台300 kV/3 ns快前沿脉冲电压源。为了得到快的前沿,设计了低电感的峰化电容和输出开关。其中峰化电容采用3个薄膜电容同轴串联设计,结构紧凑,分布电感小,电极端部的气隙结构使其能承受更高的脉冲高压,实验证明这种结构的峰化电容能承受前沿17 ns、峰值大于300 kV的脉冲高压。输出开关采用高气压小间隙SF6开关,最高工作气压1 MPa,具有较小的分布电感和火花通道电感。经实验调试,由该峰化电容和输出开关组成的峰化回路在500 kV Marx发生器的驱动下,在150Ω负载上可得到峰值电压大于300 kV、前沿小于3 ns的脉冲电压输出。

A high voltage pulse source with 300 kV peak voltage and less than 3 ns risetime was developed. The peaking circuit which consists of a peaking capacitor and an output switch is the key part of this source. The primary requirement of the peaking circuit is decreasing its stray inductance as low as possible for getting a fast risetime. Compact structures were designed especially for the peaking capacitor, the output switch and their connection. The peaking capacitor is made of three coaxial foil capacitors connected in series and the special gap structure at the end of each electrode is designed for improving its insulating ability. This capacitor can endure more than 300 kV pulse voltage with 17 ns risetime. The output switch is a SFs gas switch with high pressure （up to 1.0 MPa） and small gap （1～3 mm）, whose characteristics are obtained by experiment. Using this peaking circuit, a 300 kV pulse voltage with risetime less than 3 ns was obtained on 150 Ω load.