紧凑型MV级强流加速器输出开关

 介绍了一种水介质脉冲形成线强流电子束加速器的输出开关的设计和实验结果。水介质脉冲形成线为单同轴螺旋结构，阻抗约9 Ω，充电电压为1.2 MV，匹配负载输出电压600 kV，脉冲宽度100 ns，形成线长度1.1 m，最大外径35 cm。输出开关采用简单的自击穿火花开关形式，主要采用了以下设计原则：（1）电极间隙的场增强因子小于1.4，使SF6的击穿电压 压强曲线尽可能线性；（2）电极间平均场强300 kV/cm，大于材料沿面界面场强的3倍以上，避免发生沿面闪络；（3）控制各结合点的场强，使其小于30 kV/cm；（4）减少开关室的体积，以保证最大的机械强度。该开关结构紧凑，总长度为12 cm，电感小于100 nH、击穿电压和气压的线性关系好，可在0.3~1.2 MV的较宽范围内调节。实验中开关运行稳定可靠，达到了设计要求。

compact output switch for megavolt e-beam accelerator

A compact output switch for a water pulse forming line(PFL) e beam accelerator was designed. The accelerator is of the helical coaxial PFL type, having impedance of 9 Ω, and charging voltage 1.2 MV, and outputs 600 kV, 100 ns on matched load. The length of PFL is 1.1 m, and diameter less than 35 cm. The output switch is of the simple self-breaking gas type, designed following these principles: (1) it’s field enhancement factor is 1.4, which makes it possible to have a near linear curve for SF6’s voltage-pressure curve; (2) field within the gap is 300 kV/cm, 3 times stronger than that along the insulator, which prevents surface flashover; (3) field at triple points is controlled within 30 kV/cm; (4) the volume of switch is minimized to enhance its mechanical strength. The lengh of switc