基于谐振电路的固态Marx发生器的顶降补偿

Voltage droop compensation based on resonant circuit for solid-state Marx generators

在诸如粒子加速器等应用中,要求高压脉冲的电压、电流顶降尽可能低。减小顶降的常用方法是增加储能电容器的容量,但代价是系统的能效较低、体积较大、功率较高。另一种方法是插入一些特殊级来补偿电压顶降。在固态Marx发生器中,当谐振电感和补偿开关串联起来与普通级中的主电容并联时,就得到了补偿级。本文在16级单极性固态Marx发生器中加入了四个基于谐振电路的补偿级,以补偿不同负载、不同脉宽下的电压顶降。在放电过程中,将正弦电压的近线性部分加到负载上作为补偿,实现了几乎无电压顶降的矩形脉冲。不同的补偿级数可以对电压顶降进行不同程度的补偿,补偿效果也是可调的。此外,只要关断谐振管,这些补偿级也可以作为固态Marx发生器中的普通级工作,从而加以利用。由于谐振补偿级中的电容也与Marx电路中的电容并联充电,因此不需要辅助电源充电。实验结果表明,在400Ω和5 kΩ阻性负载上,2.5 kV和10.5 kV脉冲的电压顶降分别都能得到理想的补偿。为了获得更好的补偿效果,脉冲宽度应小于正弦电压的近线性部分的长度。

The voltage droop of high-voltage pulses is required to be as low as possible in many industrial applications including particle accelerators.The commonly used method of reducing the droop is to increase the capacitance of the energy storage capacitors at the price of lower energy efficiency,bigger size,and higher power of the system.Another method is to insert some special stages to compensate for the voltage droop.When a resonant inductor and a switch in series are connected in parallel with the capacitor in a common stage in solid-state Marx generators(SSMGs),a compensation stage is obtained.In this paper,four compensation stages based on resonant circuit have been inserted into a 16-stage SSMG to compensate for the voltage droop with different loads and different pulse widths.The nearly linear part of the sinusoidal voltage is precisely added to the load during discharge as compensation and the rectangular pulsed voltage with little droop can be realized.Different numbers of compensation stages can compensate the droop to different levels,which means the compensation effect is also adjustable.Moreover,these compensation stages can also operate as common stages in Marx generators as long as the resonant circuits are open.Since the capacitors in resonant compensation stages are also charged in parallel with capacitors in common stages,no auxiliary power supply is required.Experimental results show that the droop of 2.5 kV and 10.5 kV pulses can be ideally compensated over 400Ωand 5 kΩresistive loads,respectively.The pulse widths should be shorter than the length of the nearly linear part of sinusoidal voltage for better compensation effect.